ISSN 0289-842X

RIKEN
Accelerator
Progress Report
vol.

26

理化学研究所

The Institute of Physical and Chemical Research (RIKEN)RIKEN Accelerator Progress Report 11 (Q)(Q)O))January-December U1/ 1/ ~JJ. it. $ Mf ~ jilTThe Institute of Physical and Chemical Research (RIKEN)
Walco-shi, Saitama, 351-01 JAPANEditors
S. AmbeA. AndoM. HaraT. Ichihara

T. Kambara

Y. Miyazawa

I . Shimamura

I . Tanihata

E. Vagis. Yamaji

Y. YanoF. Yatagai

All rights reserved. This report or any part thereof may not be reproduced in any form
(including photostatic or microfilm form) without written permission from the publisher.
All reports are written on authors' responsibility and thus the editors are not liable forthe contents of the report.

CONTENTS

Page
I.

INTRODUCTION .........................................................................................................

II.

OPERATION OF ACCELERATORS11.

RRC Operation .................................................................................................

3

2.

RILAC Operation ...........................................................................................

4

3.

AVF Cyclotron Operation ...... ·...... ·................................................................

6

4.

Tandetron Operation ... ..................................................................................

7

III.

RESEARCH ACTIVITIES

1.

Nuclear Physics
1.

Study of a Decays Following 40 Ar Bombardment on 238U .......................... ·92.

Electromagnetic Transition Probabilities in the Natural-Parity
Rotational Bands of 155,157Gd .. , ......... .......................................... ...... .............

10

3.

Lifetime Measurement of a New Isomeric State in 145S m ...........................

11

4.

High-Spin Isomer Beams ..............................................................................

12

5.

Neutron Emission for the Fusion of 4°Ar+Ni, 92Mo, 122Sn
Reactions at E/ A=26 MeV .......................................................................... · 13

6.

Complex Fragment Distributions in 84Kr+ 27 AI at E 18b =10.6 MeV /u .........

14

7.

Search for a Bound State of a Negative Pion and Neutrons in
180+ Be Collisions .;........................................................................................

15

8.

Pion Absorption in the GeV Region .............................................................

16

9.

12C(12C, 12N)12B Charge-Exchange Reaction at E/A=135 MeV ..................

17

10.

Deuteron Breakup Reaction at Intermediate Energies .................... .............

18

11.

Coulomb Breakup of BB .................................................................................

19

12.

Sub-barrier Fusion with Unstable Neutron-rich Nuclear Beams ...............

20

13.

Measurements of 11 Li + p and 9Li + P Elastic Scatterings at 60 MeV .... .......

21

14.

Coulomb Dissociation of llLi on a Lead Target at 43 A MeV .................. · 22

15.

Mass Measurements of Neutron-Rich Unbound Nuclei by
Break-Up Reactions ......................................................................................

23

16.

Momentum Distribution of Projectile-Rapidity Neutrons from
6,8He, 9,l1Li Projectiles at 800 and 72 MeV/nucleon .....................................

24

17.

Revelation of Thick Neutron Skins in Nuclei .............................................

25

18.

g-Factor Measurement of 21F Ground State ................................................

26

19.

Spin Polarization of 43Ti Fragment from 116 A MeV 46Ti Beam" ...... .......

27

Page
20.

Proton Elastic Scattering with 9Li and llLi and Its Halo Structure ...........

28

21.

Langevin Approach to Pre-:-scission Neutron Multiplicities andFragment Kinetic Energies ...........................................................................

29

22.

Systematics of Isotope Production Rates
Fission Products and Their Barrier Penetration .. ·.. ...............................

30

23.

Nucleus as a Canonical Ensemble: Deformed Nucleus ................................

31

24.

An Application of Multi-precision Arithmetic in Physics
Nucleus as a Canonical Ensemble .........................................................

32

25.

Strength Distribution of Isoscalar Vibrations around Thermal
Equilibrium ..........................'...........................................................................

33

26.

Quantal vs. Semi-Classical Treatment of Nucleon-Nucleon Collisions .....

34

27.

Structure of Neutron Rich Nuclei
A Typical Example of the Nucleus 11 Li ................................................

35

28.

Analysis of 9Li + n Resonances in lOLi by the Complex Scaling Method
Interaction between 9Li and Neutron ...................................................

36

29.

Two-Neutron Removal Cross Sections of 11Li .............................................

37

30.

Higher Order Electromagnetic Interaction in the 8B Breakup Process ......

38

31.

Possible Existence of a Bound State in iLi ................................................

39

32.

~He Hypernuclear States and Roles of the Spin-Isospin Term of
I-N Interaction .. ............ ... ................................. ...... ............ ............... ...... ....

40

33.

Highly Excited States of XLi by the Microscopic Cluster Model ................

41

34.

Light I Hypernuclei I- Atoms .................... .................................................

42

35.

Production of Double A Hypernuclei from a Formed :3
Hypernuclear State ..................................................... ..................................

43

36.

URASiMA: An Event Simulator for URHIC ............. ...................... ...... .......

44

37.

Multiplicity Dependence of the Chaoticity Parameter in HBTMeasurements ................................................................................................

45

38.

Pion Double Charge Exchange Reactions Leading to Double
Pionic Atoms ..................................................................................................

46

39.

Formation of Deeply Bound Pionic Atoms by (d,3He) Reactions .............

47

40.

Relativistic Mean Field Theory and Skyrme Hartree-Fock Theory for
Unstable Nuclei .............................................................................................

48

41.

Application of the Relativistic Mean Field Theory to Deformed Nuclei ...

49

42.

Equation of State in the 1/ N Expansion of a Relativistic Many-Body
Theory ............................................................................................................

50

43.

Fermi-Liquid Properties of Nuclear Matter in the 1/ N Expansion of a
Relativistic Many-Body Theory· ...... ·.... ·...................... ·.......... ·.... ·.......... ·....

51

A Modified Nambu-Jona-Lasinio Model for Mesons and Baryons ............

52

44.

Page

2.

45.

Faddeev Approach to the Nucleon in the Nambu-lona-Lasinio (N1L)
Model ..............................................................................................................

53

46.

Nuclear Transparency in (e, e'p) and (p, 2p) Reactions ...........................

54

47.

Chiral Symmetry Restoration inside Flux Tubes of Hadrons .............. .......

55

48.

Chiral Solitons at Finite Temperatures ........................................................

56

49.

Chiral-Symmetry Restoration in a Strong Color-Electric Field andHadron Structure ..........................................................................................

57

50.

Large-scale Numerical Simulation of the Three-state Potts Model

58

Atomic and Solid-State Physics
1.

Production of Inner-Shell Vacancies in Energetic Ar Ions Penetrating
Solid Targets .................................................................................................

59

2.

Measurement of RER X Rays from 0.8 Me V /nuc1eon Ar Ions Excitedby a Foil .........................................................................................................

60

3.

Measurement of RER X Rays from 37 MeV /nuc1eon Ar Ions Excitedby a Carbon Foil ............................................................................................

61

4.

Coincident Charge States Distributions of Recoil and Scattered Ionsin 26 MeV Ne-Ne Collisions .........................................................................

62

Multiply Charged Ions Produced from Gaseous and Condensed CO
Targets under Energetic Ion Impact ............................................................

63

6.

Measurement of Ejected Electron from Quartet State of N4+** (ls3131')
Created by N6++0 2 Collisions ......................................................................

64

7.

Binary Encounter Peaks for 0° Electrons in Collisions of
0.8 MeV /nuc1eon Bi q + with H2 and He ........................................................

65

Search for -MeV Electrons Produced by 95 MeV /nuc1eon Ar Ions
Bombarding C, Ni, Au Foils ...................... ·.................. ·.. ·...... ·.. ··.. ..............

66

9.

Beam-Foil Experiment of Neonlike Iron ......................................................

67

10.

X-ray Studies on Muon Transfer Reactions from Hydrogen to Helium'"

68

11.

Measurement of Isotope Shift of Molybdenum by Resonance
Ionization Spectroscopy .................................................................................

69

12.

Radiative Lifetime Measurement of Heavy Metallic Ions in an
RF Trap
Hyperfine Levels in the 3p 1 State of Lu+ .. ..................... ............... .......

70

13.

57Fe Mossbauer Studies of YBa2 (Cul-xFex) 4 0 8 ............. :..............................

71

14.

Muon-Induced Luminescence in KBr ............................................................

72

15.

Irradiation-Enhanced Solid Krypton Formation in Kr-Implanted
Aluminum .......................................................................................................

73

16.

Analysis of Damage in Both Eu- and Tb-Implanted CaF2 ........................

74

17.

Single Event Bum-out in Power MOSFET by High-Energy
Heavy Ion ......................................................................................................

75

5.

8.

Page

3.

18.

Exact Calculation of the Second-Born Cross Sections for
Particle Transfer into Excited States ...........................................................

76

19.

Quantum Mechanical Calculation of Slow Ion- Atom Collisions ............. ....

77

20.

Double Ionization of He by High-Energy Photon Impact ...........................

78

21.

Double Excitation of H- by Fast Proton and Anti- Proton Impact .. ..........

79

22.

Inner-Shell Vacancy Production of Fast Ar Ions in Collision with
Various Target Elements .................. ............................................................

80

23.

Resonant States of Two Electron Atomic Systems .....................................

81

Radiochemistry and Nuclear Chemistry

Preparation of Radioactive Multitracer Solutions from a High-Energy
Heavy-Ion Irradiated Au Target by Means of a Supported Liquid
Membrane (I) ........................................... .................... .................................

83

Preparation of Radioactive Multitracer Solutions from a High-Energy
Heavy-Ion Irradiated Au Target by Means of a Supported Liquid
Membrane (II) ................................................................................................

84

Separation of Multitracer from Heavy- Ion Irradiated Targets by
Heating under Reduced Pressure ..................................................................

85

Application of the Radioactive Multitracer Technique to a Study ofAdsorption of Metal Ions on a-Fe 2 03 ..........................................................

86

Radiochemical Study of Adsorption Behavior of Various Elements in
Hydrochloric Acid Solutions on Activated Carbon Fiber and a
Non-ionic Macro-reticular Copolymer Using Multitracer ..........................

87

Utilization of Multitracer Solutions for Studies on the Ion Exchange
Behavior of a Strongly Acidic Resin NAFION ...........................................

88

7.

Multitracer Study on Complex Formation of Humic Acid .........................

89

8.

Investigation of 7 MeV/nucleon 58Ni Induced Reaction on Cu and Rh
Targets ........... ... ......................................... ....................................................

90

9.

Target Fragmentation of 141Pr and 165Ho Induced by
Heavy Projectiles ..........................................................................................

91

10.

Symmetric Mass Division in the Ir-Composite System ...............................

92

11.

Nuclear Reactions with Intermediate Energy Heavy Ions on
V, Cu, Nb, and I ..........................................................................................

93

12.

Nuclear Reactions Products in the Interaction of 197Au andIntermediate Energy Heavy Ions 14N. 15N. and 4°Ar .................................

94

Time-Differential Perturbed-Angular-Correlation (TDPAC) of y-Rays
and Emission Mossbauer Spectroscopy of 99Ru in YBa 2 Cu 3 07-x Using
99Rh as a Source Nuclide ..............................................................................

95

14.

Magnetic Moment of Ru Atoms in Fe3-xRuxSi .......... ...... ..................... .......

96

15.

The Influence of Light Element Mixture on the Lifetime of Carbon
Stripper Foils ............... ........ ............. ...... ... ... ............... ...... ...... ... ............ .......

97

1.

2.

3.

4.
5.

6.

13.

Page

4.

5.

16.

Positron Annihilation Study on Nanometer Cavities in Porous Silicon .....

98

17.

Recovery and Clustering of Defects in GaAs Studied by Mean of
Positron Annihilation .............. ............ ...... ............... ............ ...... ... ...... ...... ....

99

Radiation Chemistry and Radiation Biology

1.

LET Dependent Competition between Radiative and N onradiative
Annihilations of Core Holes Produced by Ion Irradiation of
BaF2 Single Crystal ....................................................................................... 101

2.

Depth Resolved Dynamics of Ion-tracks
Correlation between VUV - and VIS-Excimer Luminescencefrom Ion-Irradiated Dense Helium ......................................................... 102

3.

Radiation Effects of Ion-particles on Various DNA Structures .... ...... ....... 103

4.

Further Studies on Sensitivity of XP Cells to Heavy Ions .. ·.... ·........ .......... 104

5.

Effect of Carbon Beam Irradiation on Human Monolayer Cells ............... 105

6.

LET Dependence of PCC Breaks in Human Embryo Cells Irradiatedwith Carbon Ions ............................................................................................ 106

7.

Tumor Control Probabilities and Tumor Growth Delay after
Accelerated Carbon Ions .............. .... ............... ............ ............ ......... ...... ....... 107

8.

Early Skin Damage in Mice after Single Doses of Accelerated Carbons ... 108

9.

Studies on Induced Mutations by Ion Beam in Plants
Induced Mutants of Rice Resistant to Bacterial Leaf Blight ............... 109

10.

Somatic Mutation Frequencies Induced by Ion Irradiations in Soybean
Strain L65 Heterozygous at the Leaf Color Locus ~l ................................ 110

11.

Effects of Heavy Ions on Fish Development ................................................ III

Instrumentation

1.

Development of New Data Acquisition System at RIKEN Ring
Cyclotron Facility .......................................................................................... 113

2.

Computing Environment around the Accelerator Facility ...... ·· .......... ·.... ·.. · 114

3.

High-Resolution Dispersive-Mode Beam Transport to theSpectrograph SMART .................................................................................... 115

4.

A Proportional Scintillation Imaging Chamber for Heavy Ion Detection'" 116

5.

Heavy-Ion Radiation Damage on Position-Sensitive Silicon Detector ....... 118

6.

Straggling of High Energy Heavy Ions in Silicon Detectors ...................... 119

7.

Calibration Experiments for the Identification of Isotopes by Telescopes
HEP-MIs aboard the Geotail Satellite ......................................................... 120

8.

Detection of Scintillation Photons in Liquid Xe from Heavy Ions andTheir Attenuation Length .............................................................................. 121

9.

Isotope Separation of a Cosmic Ray Telescope .......................................... 122

10.

Collinear Laser Spectroscopy with Ion-Guide Beam ................................... 123

Page

6.

IV.

11.

Atomic Beam Magnetic Resonance Apparatus for
Systematic Measurement of Hyperfine Structure Anomalies(Bohr-Weisskopf effect) ............................................................................... 124

12.

High Resolution PIXE Using Imaging Plate ..... ......... ... ............... ........ ........ 125

13.

Total Reflection X-Ray Photoelectron Spectroscopy

Material Analysis
1.

Molecular Orbital Calculation of Sulfur Kf3 X-Ray Spectra ...................... 129

2.

Low-Energy Satellite Structure of Ca",Fe Ka ............................................. 130

3.

Chemical Specification by High Resolution PIXE ....................................... 131

5.

Singularity of Clay Minerals and Iridium Concentration at
a Cretaceous-Tertiary (K-T) Boundary ...................................................... 132

6.

Structural Water in Volcanic Glass······························································ 133

NUCLEAR DATA

1.

Status Report of the Nuclear Data Group

2.

Radiobromine Nuclides and 75Br Production Cross Section ........................ 136

V.

DEVELOPMENT OF ACCELERATOR FACILITIES

1.

Ion Accelerator Development

2.

127

135

1.

Recent Development of RIKEN 10 GHz Electron Cyclotron
Resonance Ion Source .................................................................................... 137

2.

RIKEN High Intensity Polarized Ion Source andDeuteron Polarimeters···················································································· 138

3.

Development of the LN A Laser for Polarized 3He Ion Source of the
Injector AVF Cyclotron (III) ........................................................................ 139

4.

A Beam Chopper for RILAC Using High Speed MOS-FET Modules ........ 141

5.

Construction of the Second-Harmonic Buncher for RILAC ........................ 142

6.

Profile Monitor for Light-Ion Beams with High Energy.................. .......... 144

Synchrotron Radiation Source Development
1.

Study on the Low a Operation of SPring-8 Storage Ring .......................... 145

2.

Estimation of Increase in Vertical Emittance Due to the Vertical
Dispersion Induced by Magnetic Errors ........................................................ 147

3.

Effects of Multipole Errors on the Dynamic Aperture ofSPring-8 Storage Ring (III) .......................................................................... 149

4.

Effects of Ground Tremor on the Orbit Distortion ofSPring-8 Storage Ring .................................................................................. 151

5.

Geodesy for the Storage Ring of SPring-8 ........ ..................... ............... ....... 153

6.

Status of SPring-8 Magnet System ............................................................... 154

7.

Magnetic Field Measurements with Improved Harmonic Coils .................. 155

VI.

8.

Design of Injection Section for the SPring-8 Storage Ring ..... ...... ...... ... .... 156

9.

Power Supply System for SPring-8 Magnet ................................................ 157

10.

High Power Test Results of a Prototype Single-cell Cavity for the
SPring -8 Storage Ring .................................................................................. 158

11.

Higher Order Modes of Single Cell Cavities for the SPring-8 .................... 159

12.

Impedance Estimation of the SPring-8 Storage Ring ................................. 160

13.

Design of Aluminum Alloy Conflat Flange for SPring-8
Storage Ring ........ .................. ............. ..... ................. .......... ........... .......... ... .... 161

14.

Sealing Performance of AL/SDS Conflat Flanges ....................................... 162

15.

Photodesorption for OFHC-class 1 by High Energy Photon ............ ........... 163

16.

Electrical Parameters for the Operation of a Titanium Sublimation
Pump ........................................................................... .................................... 164

17.

The Outgassing Characteristics of Titanium Sublimation Pump' ............... 165

18.

Reproducibility of Outgassing Rate at DHV Chamber ................................ 167

19.

Outgassing Rate Measurement of Alumina Sample .................................... 169

20.

Outgassing Rate Measurement of BeCu Sample ........ .............. .................... 171

21.

Support for a Normal Cell Vacuum System ................................................ 173

22.

Development of the LynxOS Device Drivers ................................................ 174

23.

Test of VME Remote I/O System Slave Card Type- A ........ ...................... 176

24.

Design of RF Low Power System for the SPring -8 Storage Ring.............. 178

25.

On the Temperature Dependence of an Optical Fiber and Related
Modules for the Timing System of the SPring -8 ......................................... 179

RADIATION MONITORING
1.

Radiation Monitoring of RILAC, T ANDETRON ,and Hot Laboratory·· ...... ... ............ ... ...... ... .... ........ ... ...... .............. ... .............. 181

2.

Exposure Dose Monitoring for Radiation Workers at
RIKEN Accelerator Research Facilities .................. .. .................................. 182

3.

Measurement of Neutron Flux with the Activation Method ...................... 183

4.

Leakage Radiation Measurements in the Ring Cyclotron Facility........ ..... 184

5.

Residual Activities in the Ring Cyclotron Facility........ ...... ............ ...... ....... 186

VII.

LIST OF PUBLICATIONS ............................................................................................. 189

VIII.

LIST OF PREPRINTS ................................................................................................... 197

IX.

PAPERS PRESENTED AT MEETINGS .......................... .............................................. 199

X.

LIST OF SYMPOSIA ................................................................................................... 213

XI.

LIST OF SEMINARS ................................................................................................... 215

Page
XII.

LIST OF PERSONNEL ................................................................................................ 219

AUTHOR INDEX

I. INTRODUCTION
M. Ishihara
This Report covers activities at the RIKEN
Accelerator Research Facility for the year of
1992. The major facility involved is anintermediate energy heavy ion accelerator
complex consisting of an energy booster,
RIIffiN Ring Cyclotron (RRC) with k=540 and
two injectors, an energy tunable linear
accelerator (RILAC) and a k=70 A VF
cyclotron. The RILAC has also been used instand alone mode, while such a utility with the
AVF is under preparation. In addition a I-Me V
Tandetron is in operation. Thus a variety ofheavy ions with energies ranging from 1 to 100
Me Vlu have served for experimental studies.
The heavy-ion beams have been used for
multiple disciplines including nuclear physics,
atomic physics, condensed matter physics,
nuclear chemistry, radiation biology and spacescience. Users have ranged over 12 among 49
laboratories in RIKEN. Besides a large numberof outside users, about 250 researchers and 70
graduate students, have participated in theactivities. International collaborations withgroups from more than 15 laboratories havealso contributed to the activities on the basis ofinstitutional agreements or individual initiatives.
This year new collaboration programs withINFN (Italy), Jyvaskyla University (Finland),Kansas State University (USA) and University
of Frankfurt (Germany) have become
operational.
The Report includes construction status
reports of two developing projects: One is a
joint project between RIKEN and JEARI tobuild an 8-GeV synchrotron radiation source(SPring-8) at the site of Harima Science Garden
City. The other is an international joint project
between RIKEN and RAL (UK) to facilitate apulsed mu~n beam at the RAL synchrotron.
The accelerators have well worked throughthe year. The RRC beam hour on the target has
exceeded the level of 5000 hours. ·Ions as
heavy as Ta have been used. With improving
performance of the ECR ion sources at the
RILAC and AVF beam intensities have been
considerably strengthened. Meanwhile apolarized ion source for hydrogen beams has
been completed at the AVF.
There has been steady development also on
the experimental apparatus at the RRC beam
channels. A projectile fragment separator RIPS
has been supplemented with a large-acceptancemagnetic spectrometer to analyze secondary
reactions using radioactive beams. Anothermagnetic spectrometer SMART, a highprecision particle analyzer, has become
available for experiments. A new setup to
produce high-spin isomer beams has been
newly installed in the El room.
Studies on nuclear physics have been madeprimarily at the RRC by consuming about 70 %of its beam hours. A strong emphasis has beenplaced on the studies on unstable nuclei. Threedifferent types of radioactive beams available,i.e., intermediate-energy beams of projectile
fragments, spin-polarized projectile-fragment
beams and high-spin-isomer beams of fusion
residues have been used. By virtue of theappreciable beam intensities secondary
reactions can be comfortably studied.
Extensive works on near-drip-line isotopes
have continued to study unique properties ofneutron-halo nuclei such as soft modes of
excitation and particle correlation in the halo.
Attempts to determine masses of off-drip-line
nuclei have been also made in several ways.
Studies on reaction rates of astrophysicalinterests have been made by observing
secondary reactions of unstable nuclei. In
particular electro-magnetic dissociation
processes were used to study inverse radiative
capture reaction rates such as on 7Be (p;y)8B,
which is related with solar neutrinos. Spinpolarized unstable nuclei have been used todetermine g-factors of neutron-rich isotopes.
Development of isomer beams is in progress
to facilitate secondary reactions with nuclei at
high-spin states. Application to synthesis ofcold and very rapidly rotating nuclei isintended. A challenging program to synthesize
super heavy elements has made a steadyprogress. A pilot experiment using a (HI,<lxn)
reaction yielded a positive indication.
The SMART spectrometer was primarily used
to study charge-exchange reactions withdeutron and heavy-ion beams. A promissing
prospect of high-energy heavy-ion direct
ractions as sprectroscopic probes wasindicated.
Experiments on atomic physics have been
made using the RRC, the RILAC and the ECR
ion source to cover a wide range of beamenergy. A study on radiative processes such as-1-

radiative electron rearrangement and radiative
Auger effect has been started in the high-energy
domain to investigate effects of the interaction
between two electrons. A study on ionizationand electron transfer processes in ion-atomclose impact collisions has been also initiatedby observing the impact parameter dependence.
Beam-foil spectroscopy has been applied to Nelike Fe ions. A study on micro cluster
formation was continued by means of heavyion irradiation on various frozen gas targets.
In the field of nuclear chemistry studies havebeen continued using tracer techniques,
hyperfine techniques, and analyzing methods interms of positron annihilation, Rutherford
scattering, PIXE and channelling effects. A
major development was achieved on the multitracer technique in which a variety ofradioacti ve nuclides produced in high-energy
heavy-ion irradiation are utilized simultaneously
to trace circulation of different elements invarious systems. New methods for preparing
multi-tracer solutions from different targets
were established. The technique has beenbroadly applied to analytical chemistry,
environmental chemistry and biochemistry.
Mossbauer, TDPAC and positron annihilation
studies were continually performed using
accelerator-produced radioactive sources on theproperties of high-Tc super conductors,
magnetic materials and semi-conductors.

-2-

Biological studies have extended over bothbasic and applied researches on heavy-ion
irradiation effects. A variety of samples such as
DNA molecules, bacterial cells and spores,
cultured mammalian cells and shrimp eggs were
irradiated to systematically study the difference
in induced damages between heavy-ion andother coventional ionizing radiations. Studies
on radiotherapy, space biology and genetic
improvement in plant were also pursued. In thedomain of radiotherapy R$D, a beam with ahomogeneous dose distribution has been
prepared by means of spreading out the Bragg
peak. The curing probability was then studied
for turner-bearing mice.
Beside experimental studies theoreticalstudies were also pursued. There were also alarge number of activities for seminars ,workshops and symposia. For example six
international meetings were organized this year.
In particular a winter school was initiatedprimarily for graduate students. It was held at
Yuzawa and will be continued every year on adifferent subject. A joint symposium between
INFN and RIKEN on heavy ion collisions was
also held for the first time at Catania.
As a whole the Facility has reached a stage ofsteady operation with increasing productivity.
In anticipation for further development in alarger scale a working group to formulate afuture project has been set up.

II. OPERATION OF ACCELERATORSRIKEN Accel. Prog. Rep. 26 (1992)

II-I. RRC Operation
A. Goto, M. Kase, T. Kageyama, T. Nakagawa, O. Kamigaito, H. Isshiki,*
H. Akagi: R. Ichikawa: N. Tsukiori: R. Abe: K. Takahashi: S. Otsuka:
T. Maie,* T. Kawama,* T. Honma,* and Y. Yano
Table 1 lists the characteristics of ion beams that weredelivered from November 1991 to October 1992. We
operated the ring cyclotron for 161 days for beamservices to users (excluding tuning time) during thisperiod. We started to accelerate polarized deuterons of
135 MeV/nucleon. The 4°Ar ions of 7.5 MeV/nucleon
were accelerated without charge stripping between
RILAC and the ring cyclotron. There was one
cancellation of scheduled machine-time (2 days) becauseof a vacuum trouble in one of the resonators, which wascompensated later.
We took a long summer-time shutdown (for 45 days)
for the following improvements:
1) 464 pieces of joints of cooling-water pipes for all
the trim coils, located just outside the accelerationchamber, were removed, and the pipes were directly
rejointed by welding, because the joints had beendamaged due to electrical corrosion.
2) 128 pieces of O-rings of cooling-water joints usedin the movable-boxes of the resonators were replaced
from P9 to PI0A having a slightly larger crosssection, because the vacuum of the accelerationchamber had been sometimes broken down due toleaking troubles at these joints.
3) The EDC (deflector) was replaced by a new typewhose high-voltage feed-throughs are accommodated
in a chamber filled with high-pressure SF6 gas.
4) The MDCl (magnetic channel) was replaced by aspare.
5) The nylon hoses used for cooling-water inside trimcoil power supplies were replaced by Synflex hoses,
because the nylon hoses had been deteriorated.
6) A twenty-frrst phase probe was newly installed.
In an attempt to increase the beam intensity fromRILAC, we decided to add a new beam buncher of thesecond harmonic on the injection beam line. The designof it was finished and the whole system will becompleted at the end of next March. Besides, a new
ECR ion source and a frequency-variable RFQ, which isplanned to be installed as another injector of RILAC in
the same attempt, is being designed.

Table 1. RRC beams accelerated in November 1991 - October 1992.
Particle

Charge

RFF

h

(MHz)

dt
pol. dt
H2t
12Ct
t
14N
160t
180
2~et

22Net
4°Ar ttt
136Xet

1
1
1
1
6
6
6

7
8
8
10
10
5
14
14
17
23
31

29.0
32.6
32.6
32.6
28.0
29.0
32.6
32.6
26.2
29.0
32.6
24.6
18.8
30.0
33.0
29.1
19.5
28.0

5
5
5
5
5
5
5
5
5
5
5
5
11

9
9

5
10
9

Energy(MeV/nucleon)

Beam time(days)

100
135
135
135
92
100
135
135
80
100
135
70
7.5
30
38
95
10
26

1
9
3.5
3.5
8
10.5
17.5
7
3.5
21.5
4
4
25.5
2
8
24
6.5
2

Total
t New beams* Sumijyu Accelerator Service, Ltd.
-3-

161

RIKEN Accel. Prog. Rep. 26 (1992)

11-2. RILAC Operation
E. Ikezawa, M. Hemmi, M. Yanokura, M. Kase, T. Aihara: T. Ohki,·
H. Hasebe,· T. Chiba, Y. Chiba, and Y. Miyazawa
This year, RILAC has been operated for
164 days, and has supplied various kindsof ion beams for experiments. Table 1 gives
the statistics of operation from Jan. throughDec. 1992. Table 2 summarizes the timesharing for individual research groups. The
percentage of .the beam time for RIKEN
Ring Cyclotron (RRC) was about 32 %. Ionsof 4OAr, 186Xe, and 181Ta accelerated by RILAC
were injected to RRC. Table 3 gives thestatistics of ions used this year. Beams of
27 ion species have been used forexperiments. About 57 % of the total beamtime was devoted to 40Ar ions. Metallic ions
Table 1. Statistics of the operation from Jan. 1
through Dec. 31, 1992.
Day%

Beam time

164

44.8

Frequency change

15

4.1

Overhaul and improvement

27

7.4

Periodic inspection and repair

34

9.3

Machine trouble

2

0.5

124

33.9

366

100

Scheduled shut down
Total

were also requested frequently and the beamtime for those ions amounted to about 20 %.
Table 3. List of ions used in this year.
Ion

Mass

Charge state

Day

He

4

1

6

C

12

2

2

N

14

2,3

5

N

15

2

1

o

16

3

1

Ne

20

4

4

Si

28

5

1

Ar

40

5,6,8,9

94

Ti

48

5

3

Cr

52

7

4

Fe

56

6,9

12

Kr

84

9, 11

4

Xe

129

13

2

Xe

136

9, 15, 16

13

Ta

181

16

5

Bi

209

14, 16, 21, 22

7

We have made the following improvements:(ESQ)
was replaced with a new one, because inion production of ferromagnetic materials
such as Fe, magnetized sputtered particles
frequently formed a bridge shorting between
the electrodes and the wall; the new lens
was improved for rapid exchange of thewhole and easy maintenance. 2) An einzel
lens was installed between the ECR ion
source and ESQ in order to focus the spreadbeams from the source. As a result, thebeam transmission efficiency of the injection
beam line increased by 20 % compared withthat without the lens. 3) The power supplies
for the drift tube magnets used in thecavities No.4 and 5 were remodeled byreplacing the obsolete power transistors with
1) An electrostatic quadrupole lensTable 2. Beam time for individual research groups.
Day%

Atomic physics

44

26.8

Solid-state physics

21

12.8

Nuclear chemistry

19

11.6

Radiation chemistry

16

9.8

Accelerator research

11

6.7

Beam transportation to RRC

53

32.3

Total

164

100

• SumijyU Accelerator Service, Ltd.

-4-

the modern ones.
We have made the following developments:
1) Ions of liB, 19F, and S2S were newly
produced by the ECR ion source. At present
we can supply ions of 10 gaseous and
35 solid elements. 2) A high speed beam
chopper was installed in the injection beamline. The details are reported in this issue.!)3) We succeeded on accelerating 115 MeV
2
940Ar + and 324 Me V 209BF + ion beams. These
are new records of the maximum energies
accelerated at RILAC.
Two days of the scheduled beam time
were canceled owing to faults in NO.1 rf
amplifier and in the screen grid power
supply of NO.5 rf amplifier. The former
was induced by water splashed due to an
accident in a piping. The other machine

troubles in this year hardly affected thebeam time schedule and were as follows:
1) In a 40 MHz test operation, thin copper
sheets ( 10 cm wide, 7 cm long, and 0.3 mm
thick ), which formed an rf path between
the upper and the lower structure of NO. 3
and 6 resona tors, melted over one meterwith an anomalous rf current. 2) A screen
grid power supply of NO.2 rf amplifier, awide band amplifier for the buncher, andthe DC blocking capacitor of the final stageof NO.1 rf amplifier had troubles.
References
1) M. Hemmi et a!.: This report, p. 141.

-5-

RIKEN Accel. Prog. Rep. 26 (1992)

11-3. AVF Cyclotron Operation
A. Ooto, M. Kase, T. Nakagawa, T. Kageyama, O. Kamigaito, H. Isshiki,*
H. Akagi,* R. Ichikawa,* N. Tsukiori,* R. Abe,* K. Takahashi,* S. Otsuka,*T. Maie,* T. Kawama,* T. Honma,* and Y. Yano
Table 1 lists the characteristics of ion beams that weredelivered from November 1991 to October 1992. The
beam intensities of these ions are around several eJlA.
We operated the AVF cyclotron for 124 days for beamservices to users (-excluding tuning time) during thisperiod with no serious troubles.
We accelerated polarized deuterons from a newly
completed ion source. The acceleration was done several
times in order to measure the polarization with apolarimeter located just downstream from the AVF
cyclotron, and to deliver the beam for further
acceleration with RIKEN Ring Cyclotron. The beam
intensity was typically 300 nA and the vector
polarization about 60 % of the ideal value.
In the summer-time overhaul, we checked thepositions of elements such as the deflector, the magnetic

channel and the RF dees. We found that the position of
one of the two RF dees in the central region was shifted(rotated) in azimuthally direction by about 3 mm, which
we put back to the original position. We also checked
the electrical damage of RF contact fingers used invarious places with a result that there was no damage.
We replaced the electrode meshes of the injection beam
buncher with new ones, because the color of theirsurfaces had changed due to beam during three-yearts use.
Recently some user groups have made strong demands
to use A VF cyclotron beams for their experiments.
Until now, we have completed a chamber for use in
isotope production in the A VF cyclotron vault. We alsoplan to prepare other experimental ports in E7
experimental room, which is located below the AVF
cyclotron vault

Table 1. AVF beams accelerated in November 1991 - October 1992.
Ion

Ht
d
d
pol.d
pol.d
12(:4+
12(:4+
12(.'4+
14w+

16()5+
I8()6+"

WNe7+
22Ne6+
4OArll+RF
Frequency

Energy +(MHz)(MeV/nucleon)

16.3
14.5
16.3
16.3
16.3
14.0
14.5
16.3
16.3
13.1
14.5
16.3
12.3
14.05

7.0
5.5
7.0
7.0
7.0
5.1
5.5
7.0
7.0
4.5
5.5
7.0
4.0
5.2

Operation ++time(days)

(135)
(100)
(135)

3.5
1
9
7
3.5
8
10.5
17.5
7
3.5
21.5
4
4
24

(--- )t
(135)
( 92)
(100)
(135)
(135)
( 80)
(100)
(135)
( 70)
( 95)
Total

124

+

The values in the parentheses show the energies obtained by the coupled
operation with RRC.

++

The time served to experiments.

t

These ions were accelerated only with the AVF cyclotron.

* Sumijyu Accelerator Service, Ltd.
-6-

RIKEN Accel. Prog. Rep. 26 (1992)

11-4. Tandetron Operation
E. Yagi, T. Urai, T. Kobayashi, and M. Iwaki

The Tandetron was operated for 90 days for theexperiments in the period from Nov. 1, 1991 to Oct.
31, 1992. In the maintainance much time was taken
for the improvement of the stability of the acceleration
voltage and that of the duoplasmatron ion source. The
experimental studies on the following subjects were
made.
(1) Rutherford Backscattering Spectroscopy (RBS)(a) Behavior of Kr atoms implanted into
aluminum by a channeling method (Metal
Physics Lab.).
(b) Analysis of radiation damage in a Tb- andEu-implanted CaF2 (Semiconductor Lab. and
Surface Characterization Center).
(c) Silicide formation in Ni.-deposited Silicon-7 -(Metal Phys. Lab.).
(2) Radiation Effects(a) Radiation damage of diamond (Earth Sciences
Lab.)(3) Nuclear Reaction Analysis(a) Lattice location of hydrogen in niobium
alloys by a channeling method (Metal Physics
Lab.)(4) Particle-Induced X-ray Emission(a) Application of PIXE to biomedical,
environmental and material sciences; Traceelement analysis using energy-dispersive X-ray
spectrometry, and Chemical state analysis using
wave-dispersive X-ray spectrometry (Inorganic
Chemical Physics Lab.).

III. RESEARCH ACTIVITIES1. Nuclear Physics

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-1. Study of a Decays Following 4°Ar Bombardment on 238U
T. Nomura, M. Wada, N. Ikeda, S. Kubono, I. Katayama, K. Morita,
A. Yoshida, T. Inamura, M. Kurokawa, T. Motobayashi, H. Murakami,
S. Furuya, Y. Nagai, H. Kudo, K. Sueki, M. Tanikawa, I. Nishinaka,
H. Nakahara, T. Shinozuka, H. Sunaoshi, M. Fujioka, H. Miyatake,Y. Fujita, T. Shimoda, and K. Tsukada*
NUCLEAR REACTION, 238U(40Ar,a.2n), 238U(40Ar,4n),E=5.1 MeVlu; measured a decays, spontaneous fission;

1[ gas-fuled separator.

Because the a emission from a highly
excited nucleus can efficiently cool it down
both in energy and angular momentum, the(HI,axn) type reaction is expected to be a
promising way of producing heavy fissile
nuclei, in which the fission width is far larger
than the neutron emission width. Therefore,
we have recently carried out a measurent on
the 238U(40Ar,a2n) reaction by using the
RIIffiN gas-filled separator (GARIS). Since
the detailed analysis is now in progress, wewill briefly describe here its experimental setup shown in Fig. 1.
A 7.5 Me Vlu 40Ar beam of about 100 pnA in
intensity was supplied from the Ring
Cyclotron. The bea..'1l energy was degradeddown to 5.14 MeVlu through a 5.55 Jlffi Havar
foil placed between the GARIS and vacuum
regions as well as through a target backing (15Ilm Al foil), onto which a 238U 308 target ofabout 1 mg/cm 2 thickness was mounted. In
this set-up the reaction products collected by
the GARIS first pass the TOF system
consisting of two micro-channel plateassemblies placed 50 cm apart from eachother, and then enter a two dimensional
position-sensitive Si detector (PSD) set at the
focal plane of the GARIS. Each micro-channel
plate assembly is composed of a 1 J.1ffi mylar*

Jpn. At. Energy Res. Inst- 9-

Path of Reaction
Products
Target (waterDcooled)Harvar~::C*"""'~+-~=:rfOil,,,--_/MCP Assembly

PSD:se::ming~ II "":~ :~tmnnnnn
particles:::: I" " 8. I U1lJlllJlJlJ
12 strips. ---mylar MCP
Fig. 1. The present experimental set-up.

foil of 80 mm in diameter and a micro-channel
plate of 70 mm in diameter, while the PSD is
60 mm high and 60 mm wide.
The measured space resolution of the PSD
turned out to be 0.3 mm for fission fragments,
whereas it was around 3 mm for 5.5 MeV aparticles. The PSD signals were used to trigger
the data taking. Each event array consists ofsignals of the MCPs, TOF if both the MCPs
are on, the energy signal detected in the PSD,
and the absolute clock signal. The mass
analysis of the residual nuclei reaching the
PSD will be done from the measured TOF andenergy signals.

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-2. Electromagnetic Transition Probabilities in the Natural-Parity
Rotational Bands of 155, 157 Gdt
H. Kusakari, M. Oshima, A. UChikura;l M. Sugawara, A. Tomotani, *1
S. Ichikawa,*2 H .. Iimura;2 T. Morikawa, T. Inamura, and M. Matsuzaki*3
NUCLEAR REACTIONS 155,157Gd(58Ni,58Niy), E=240 MeV; 155,157Gd(81 Br,]
81Bry), E=305 MeV; measured Ey, y-ray angular distributions, y branchings[
and E2/Ml mixing ratios, nuclear lifetimes.

The ground-state rotational bands of 155Gd and
157Gd have been investigated through themultiple Coulomb excitation with beams of 240MeV 58Ni and 305-MeV 81 Br from the tandem
accelerator at Japan Atomic Energy ResearchInstitute at Tokai.
We have previously reported the "inverted"signature dependence of Ml strength B(Ml) in thenatural-parity rotational band of 163Dy.1,2)
This has drawn considerable attention since thesignature dependence is unexpectedly large andthe phase of the zigzag pa ttem as a function ofspin contradicts the well~known selection rule forunique~parity rotational bands based on high-j
orbits. 3) In tenns of the cranking model we haveshown that the inverted signature dependence islikely to originate from the characteristic
coherence between the orbital spin configurationsin the spin-down (Q=A-l/2) dominant onequasiparticle states. 2 ) On the other hand, thecounterpart, i.e., the spin-up (n=A+l/2)
dominant configurations show almost no signaturedependence of B(Ml), being consistent with thecranking model. 4 ) In order to further study thegeneral feature in this mass region, we carried out
multiple Coulomb excitations of 155,157Gd whose
ground states possess comparable magnitudes ofthe spin-down and spin-up configurations.
The ground-state rotational bands of 155,157Gd
are commonly based on the natural-parity

t Condensed from the article in Phys. Rev., C46, 1257

(1992).
+1 Chiba Univ.
+2 Jpn. At. Energy Res. Inst.
+3 Fukuoka Univ. of Education.

-10-

Nilsson state v[521,3/2]. We have assigned
levels up to Ft=25/2- in 155,157Gd. Measured
were y-rays and their branchings, E2/ Ml mixing
ratios; nuclear lifetimes were also measured by
the recoil distance method and the absolute
intraband transition probabilties up to the 21/2state in 155Gd and the 23/2- state in 157Gd were
determined.
By comparing the present results especially for
155Gd with those for 163Dy and 173Yb whichwere previously reported, 2,4) it has been foundthat, in terms of the cranking model, thesignature-averaged magnitude of B(Ml) becomes
smaller than the experimental one and theinverted signature dependence does more
conspicuous as the spin-down components increase.
For the case of 157Gd, the calculation somewhat
deviates from the observed B(Ml) at high spins.
As for B(E2) values, however, the experimental
trend as a function of spin is well reproduced by
the calculation.

References
1) E. Minehara, M. Oshima, S. Kikuchi, T. Inamura, A.
Hashizume, and H. Kumahora: Phys. Rev., C3S, 858(1987).
2) M. Oshima, E. Minehara, S. Kikuchi, T. Inamura, A.
Hashizume, H. Kusakari, and M. Matsuzaki: Phys. Rev.,
C39, 645 (1989).
3) I. Hamamoto: Phys. Lett., 1068, 281 (1981).
4) M. Oshima, M. Matsuzaki, S. Ichikawa, H. Iimura. H.
Kusakari, T. Inamura, A. Hashizume. and M. Sugawara:
Phys. Rev., C40. 2084 (1989).

RIKEN Accel. Prog. Rep . 26 (1992)

111-1-3. Lifetime Measurement of a New Isomeric State in 145Sm
A. Ferragut, Y. Gono, T. Murakami, T. Morikawa, Y.H. Zhang, K. Morita,
A. Yoshida, M. Oshima, H. Kusakari, M.Sugawara, M. Ogawa, M. Nakajima,
J.C. Kim, S.J. Chae, B.J. Min, S. Mitarai, E. Ideguchi, T. Shizuma, and A. Odahara[Nuclear reaction, isomeric state, secondary beam, recoil-ion separator, 145Sm.]

Secondary beams give . the possibility to
explore high-spin physics by means of Coulomb
excitation or nuclear reactions of the high-spin
nuclei in a second target. To estimate the counting
rate of high-spin nuclei at the latter position,
the knowledge of .their half-life is required.
An isomeric state of 13 ns half-life and 1105
keV energy in 145Sm has already been found byusing light ions as projectiles, 1) and fusionneutron evaporation as a production reaction. By
means
of
a
heavy
ion
reaction,160(136Xe,7n)145Sm at a bombarding energy of
7.5 MeV/A, we were able to populate higher
excited levels and we found an excited state witha half-life of 956.8 ns (+192.5 ns, -148.9 ns).
The reaction products were collected by usinga gas filled recoil ion separator 2) and stopped ona catcher which consisted of a plastic scintillator
placed at the focusing position and kept invacuum. Seven BGOACS Germanium (Ge)detectors were placed around the catcher where
the high-spin states decayed. Coincidence events
obtained with Ge-Ge and Ge-plastic coincidences(triggers) were recorded, and the corresponding
gamma energy spectra were measured by theGermanium detectors (Fig. 1 for the Ge-plastic
events). Time difference distributions between
the germaniums and the plastic were measured
for the Ge-plastic coincidence events.
Figure 1 shows clearly all the transi tions
previously observed in Ref. 1 and therefore,
proves that 145Sm is produced with a highefficiency. Since the time of flight of 145Sm fromthe production target to the catcher is at least
150ns, and since all the reported states above theknown isomeric state (1105 keV) have half-lives
below the nanosecond range, 1) another isomericstate must be produced at the production target.
Moreover, by using the Ge-Ge coincidence data,
we determined that most of the importanttransitions shown in Fig. 1 are coming from thedecay of the new isomeric state.
Therefore, the structure observed in the
distribution of the time difference between theplastic scintillator and the germaniums is
attributed to the decay of the new isomeric state.

After a proper background substraction, thedistribution shown in Fig. 2 is obtained and thehalf-life mentionned above is extracted.
., •• 'lc- •••••

•
C
:J

o
o

.

pl.u. le - ' ••••

CII

1460.7

D

<OK

E
:J

Z

E (keV)

Fig. 1. Gamma energy spectrum for Ge-plastic
events. Triangles show the known transitions in
145Sm and arrows the new ones.

1000_----------......,
....
'ii

;;

100

1000

2000

Time

(n.)

3000

~OOO

Fig. 2. Distribution of the time difference between
the plastic and the germaniums for the Geplastic coincidences. Background substracted.
References-11-1) M. Piiparinen et al.: Z. Phys. , A338, 417 (1991).
2) K. Morita et a1.: RIKEN Accel. Prog. Rep., 21, 155(1987).

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-4. High-Spin Isomer Beams
Y. Gono, T. Murakami, T. Morikawa, A. Ferragut, Y.H. Zhang, K. Morita,
A. Yoshida, M. Oshima, H. Kusakari, M. Sugawara, M. Ogawa
M. Nakajima, S. Mitarai, A. Odahara, E. Ideguchi,
T. Shizuma, M. Kidera, j.C. Kim,
S.]. Chae, and B.]. Min
Nuclear Reactions 14Ne36Xe,6n)144Pm, 160(136Xe,7n)145Sm, 20NecI36xe,9Iy14 7Gd,
8.5-10MeV/u;
Gas Filled Recoil Separator; found new High-Spin Isomers of144pm , 45Sm ,[High-Spin Isomer Beams.
Experiments to search for high-spin isomers
were performed using 136Xe beams of 8.5 and
10 MeV/u. The beams were provided by the
RIKEN Ring Cyclotron. The reactions usedwere the 14N(136Xe,6ny44p m, 160(136Xe,7n)14SS man d 20Ne(136Xe,9n)147Gd. The
reaction products were transported to a catcher
which was made of a 0.2mm plastic scintillator
and placed at 6m down stream from the target
position. The beam lines were filled with He,
N2,Ne or Ar gases to equilibrate the charge
states both of the reaction products and theprimary beams so that the width of the charge
state distribution could be reduced. The N2 andNe gases worked as targets to produce 144Pm
and 147Gd as well. A Si02 target of 2mg/cm2
was used to produce 145Sm . Two new isomers
were found in 144p m an d 145S m at theexcitation energies of 7.5 and 8.7 Me V,
respectively, which were determined tentatively
by the analysis of yy-coincidence data. Theirprobable spin values are assigned to be 27+
and 49/2+ based on the systematics of isomers
and the argument of tilted Fermi surface of
N =83 isotones.
It is worth noting that these isomers includingthat of 147Gd have the recoil energies which arehigh enough to be used as secondary beams
when they are produced by the inverse
kinematics just as of the present cases. Theinteresting utilizations of these isomer beams
are the Coulomb excitation of the isomers and

-12 -

J

-:>

8~---------------------~

e

7

~

Q)

Coulomb
Barrier (Pb).•.....•.-............................. ...

>-

C)

-.
Q)

c::

6

W

~

a:

5

_-- - --------------------

4+-~--~~--~~---~~~

o

10

20

30

40

Target Mass

Fig. 1. The recoil energies of Xe induced reactions withinverse kinematics and Coulomb barriers between thereaction products and secondary targets, Be, Mg andPb.

the fusion reactions of isomer beams to produce
the cold high spin states.
Though the isomer beam intensities under thepresent conditions, a little more than 104 s-l,
are weak, the Coulomb excitation experimentwill be possible within ten days if there are E2
collective states based on these isomers withenhancement of more than 20 single particle
units.
There are many possibilities to produce
unstable nuclear beams by the fusion reactionsof inverse kinematics as shown in Fig.l. In thisfigure, the recoil energies of reaction productsof various targets bombarded by the 136Xebeams of 7 and 8 Me V/u are shown as well as
the Coulomb barrier heights between theseproducts and the Be, Mg and Pb targets.

RIKEN Accel. Prog. Rep . 26 (1992)

111-1-5. Neutron Emission for the Fusion of 4°Ar + Ni, 92Mo, 122Sn
Reactions at E/A=26 MeV t
K. Yoshida, J. Kasagi, R. Rama, *1 M. Sakurai, *2 M. Kodama, *2
K. Furutaka, K. Ieki, W. Galster,*3 T. Kubo, M. Ishihara, and
A. Galonsky
NUCLEAR REACTIONS: 40 Ar + Ni, 92M~ 122Sn at E / A = 26 Mev;]
measured neutron energy spectra and angular distributions;[ statistical model analysis; deduced level density parameters.

Coincidence measurements between residues andneutrons were performed and the level density
parameters were deduced for the nuclei wi th
excitation energies 3 - 6 MeV /nucleon where thestrong reduction of the level density parameters
was reported by Wad a et aLl)
Foils of Ni, 92Mo, and 122Sn were irradiatedwith 40Ar beams of E/ A = 26 MeV extracted fromthe RIKEN Ring Cyclotron. Neutrons weredetected with seven NE213 detectors and residues
were observed with an annular PP AC. The
neutron spectra were analyzed with the moving
source model for different residue velocities
represented by the ratios <R> between the
average residue velocities and those for thecomplete-fusion residues. Two sources, the fusion
source and the pre-equilibrium source, wereassumed in the model and the multiplicities andthe temperature parameters for both sources werededuced from the fitting.
The relation between the initial temperatureand the temperature parameter for the neutron
emission from hot nuclei was deduced numericallythrough CASCADE calculations. It is found thatthe relation T = (12/11)r is valid only for r < 3
MeV, and the relation T = 1.15r is a good
approximation at higher temperatures. The
initial excitation energy of the fused system was
kinematically evaluated from the amount oflinear momentum transferred to the fusion residue
taking into account the pre-equilibrium emission.
The extracted neutron multiplicity and theinitial temperature increase from <R> = 0.6 to 1.0.

Thus, the neutron emission can be regarded as the
decay of the thermally equilibrated fusedsystem.
As shown in Fig. 1, the initialtemperature vs. excitation-energy relation is well
explained with the level density parameter a =A /(9 ± 1) for excitation energies of 2.5 - 5.0
MeV /nucleon. No strong variation of a has been
deduced.
10
8

;;-

6

E-

4

•• SoMo2--a=N8-a=A/9- - - a=NlO

~

•

Ni

0
0

2

3

4

5

6

7

E,J A (MeV)

Fig. 1. Initial temperature versus excitation ener~ pernucleon obtained in the 40 Ar + Ni (squares), 2M 0(circles) and 122Sn (diamonds) reactions. The solid,
dashed, and dotted curves correspond to the level
density parameter a = A /8, A /9, and A / 10,
respectlvefy.
References

1) R. Wada et a1.: Phys. Rev.,C39, 497 (1989).

t Condensed from the article in Phys. Rev., C46,

. 961(1992).
*1 Ultraviolet Synchrotron Orbital Rad. Lab.,
Inst. Mol. Sci.
*2 Dept. Phys., Tokyo Inst. Technol.
*3 Universite Catholique de Louvain.

-13-

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-6. Complex Fragment Distributions in 84Kr + 27 Al at
Elab=10.6 MeV lu t
T. Nakagawa, K. Yuasa-Nakagawa, S. C. Jeong,* T. Mizota, Y. H. Pu,
Y. Futami, B. Heusch, K. Ieki, T. Matsuse, and S. M. Lee
NUCLEAR REA CfI ON 84Kr+27AI, E(84Kr)= 1O.6Me VInUc1eon:][ measuredcomplex fragment emitted from hot compound nucleus.
In order to study the decay mechanism of complex
fragments from a hot compound nucleus, we measured
the complex fragment emitted in the reaction of
84Kr+27Al at the incident energy of 10.6 MeV/u.
According to the empirical formula for complete andincomplete fusion reactions, the complete fusion is still
dominant and sequential decay is expected at the incident
energy of 10.6MeV/u.
An experiment was perfonned using a large cylindricalscattering chamber ASCHRA 1) of RUffiN Ring
cyclotron Facility. Experimental details were previously
reported. 2,3)
Figure 1 shows the angle integrated Z distribution ofcomplex fragments. One notices some even-odd effectfor Z<10 and for heavier elements the cross section
becomes smooth. At Z-40, there is a spurious peak

o

,'It

.~nl~~~. ~

t::

.9

o
(.)

I/)
I/)
I/)

10 1

o

0

aa

D

U

o.

O~DDD

J1

f>

D

which originates from the evaporation residues. The
cross sections for evaporation residues and complex
fragment emissions are 550± 100 and 500±50 mb,
respectively. The total fusion cross section obtained bysumming up the cross section of evaporation residues
and complex fragment emission is 1050 mb.
In order to investigate the decay mechanism more indetail, we compared the experimental results with thetheoretical calculation of Extended Hauser-Feshbachmethod(EHFM).4) In Fig. I, open squares show the firststep calculation and circles show the calculation withthe sequential decay. From the detailed comparison
between the experimental Z distribution and the resultsof EHFM, it turns out that the intermediate massfragment (IMF) (34~10) emission competes with thelight-particle evaporation in the first step decay and as aconsequence there is a sizable contribution of the ItviF
sequential decay after the light particle evaporation in
the final HviF yields. On the contrary, the fission decay
is dominant in the first step calculation. To verify thisconclusion more directly we are planning to perform acorrelation experiment between complex fragments andlight particles using a 3Jt phoswich detector system. 5)

D D

a

a

a

ReferencesDa
10 0 "------'--"""---'---''---'----''--.1....---''---'
20
so
o
10
30

Atomic number Z
Fig.I. The calculated results of Z-distribution for 84Kr+27Al
at 10.6 MeV/u: Closed circles are the experimental data.
Open squares and circles show the results of the first-stepand multi-step calculations, respectively.

1) T. Nakagawa et al .: RIKEN Accel. Prog. Rep., 22, 147(1988).
2) K. Yuasa-Nakagawa et al.: Phys. Lett., B283, 185(1992).
3) K. Yuasa-Nakagawa et al.: Proc. Int. Symp. Nikko'91(Nikko, June 1991) AlP Conf. Proc., 250, p.l00.
4) T. Matsuse et al.: ibid., p.112.
5) Y. Futami et al.: Nucl. Instrum. Method, A, in press.

t , Condensed from the article in Phys. Lett., B283, 185(1992).

* Inst. Phys., Univ. Tsukuba.
-14-

RIKEN Accel. Prog. Rep . 26 (1992)

111-1-7. Search for a Bound State of a Negative Pion and Neutronsin 18 0 + Be Collisions
T. Suzuki, M. Fujimaki, S. Hirenzaki, N. Inabe, T. Kobayashi, T. Kubo,
T. Nakagawa, S. Shimoura, Y. Watanabe, and I. Tanihata
NUCLEAR REACTIONS, 18 0 + Be, E =100 MeV / nucleon; particle-][ identification, deduced upper limits of o{TC-n N ), coalesence model.

A bound system of a 1t- and neutrons (pineuts) ,denoted by (1t-)nN ,. was searched in the fragmentation region of lBo + Be collisions at 100 A MeV.
So far, no experiment has been carried out forthe pineut production using a neutron-rich projectile in the projectile fragmentation region, although the Berkeley group recently searchedpineuts in the central region using heavy-ion
beams) In this note we report on a search forsingly charged pineuts (N = 2-3) using a 100 A
MeV 1Bo beam from the RIKEN Ring Cyclotron.
Experimental details can be found in Ref. 2. Eighteen among the initially recorded 3x106 events
survi ved through the analysis.
Figure 1 shows the two-dimensional distributions of the time spectrum versus the radius of

TOC (H 1- rf) channel

curvature (p) in the magnetic field, where the time
spectrum is defined between the scintillator (HI) andthe radio frequency of the cyclotron (TRF). Eighteen
events are in the figure. The hatched regions estimated from calibration runs indicate the location
where TC-n7- or TC-n3 with zero binding energy is
expected~ The widths of the bands reflect the mass
resolution of respective 2H and 3H events. Two(six) of the 18 events are within the region of thepion neutron cluster scenario as candidates for the
1Cn2 (TC-n3 ). However all the surviving 8 events locate on the fringes of the reference distribution.
Several background sources were examinedsince the background and reference distribu tion
could not be well separated. Among them protons converted at the most front scintillator by numerous forward neutrons (108 ) might be likely the
background. About 30 protons were estimated toremain through the process using a cross section,(J(n~p), of 0.07 b for 100 A MeV neutrons, which
is a comparable number to that of the candidates.
The possibility that the survived 2(6) events were
due to background sources could thus not be excluded.
If we assume that pineuts distribute uniformly inthe phase space of l1y =0.36-0.45 and 11(PJ.lm) <0.025 the upper limits of double differential crosssection at 90% confidence level, d2a/d!2dp, are 0.46
(1.07) nb/sr (MeV /e ) for n-n2 (n-n3 ). Here wetook into account the minimum lifetime of 26 ns
for the survival probability of pineuts. The data
were compared with a theoretical calculation
based on the coalesence model. 3)

Fig. 1. Plot of time spectrum versus radius of curvaturep, corresponding to the rigidity, where the time spectrum is defined between the scintillator and TRF.
Pineuts might be expected in hatched region withzero binding energy.

References
1) F. W. N. de Boer et al.: Phys. Rev., D 43, 3063 (1991).
2) T. Suzuki et al. : submitted to Phys. Rev. C.
3) S. Hirenzaki et al.: submitted to Phys. Rev. C.

5
4
__ 3

E

••

0..

2

o
1800 1900 2000 2100

2200

2300 2400-15-

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-8. Pion Absorption in the GeV Region
I. Nomura, I. Arai,*l T. Fukuda, H. Kitayama,*l P. Kitching,*2 T. Kobayashi, K. Maeda,
H. Matsuyama,*3 T. Nagae,*4 Y. Nagasaka,*l M. A. Prokhvatilov,*5 V. I. Rasin,*5
D. Rowntree,*6 M. Sekimoto,*4 T. Suda, K. Tomizawa,*l S. Ueno,*l and K. Waki*l[Nuclear reaction, 4He(x+, pp), (x+, pn), PJt= lGeV Ic, Pion absorption.]
Recently the intensive study of the pion absorption
on 3·4t-ie was carried out in the energy region below Tx
0.5 GeV at LMvlPF. PSI and TRIUMF.1- 3 ) This
energy region is characterized by the dominance of the ~resonance, and, therefore, the absorption on the nucleon
pair with isospin T= 0 is enhanced.
In the GeV region there are resonances which aremuch weaker than the A resonance. As in the ~ region,
the effect of the resonances on pion absorption can be
expected to result from a mechanism of this region.
The energy dependence of the absorption cross sections
on Deuteron,4) however, shows no clear structure. Thiscan be considered to be due to that the reaction is notaffected by the resonances or the effect of resonances are
smeared out. The measurements on a Deuteron target
show directly the absorption cross section on the
nucleon pair with T=O, and there is no data of that for
the T=1 pair in this region. One of our aims is toobtain the elementary absorption cross sections on the
nucleon pair with T=l and T=O, in order to investigate
the absorption mechanism in this region.
As the first experiment, we have measured the (x+,pp) and (x+, pn) cross sections on 4He at P3t = 1 GeV/cusing 12GeV Proton Synchrotron at National
Laboratory for High Energy Physics(KEK). The
preliminary analysis shows that the angle-integrated
cross section ratio R = o(x+, pp) I o(x+, pn) is theorder of one, while in the ~ region it is about 20. Thismeasured ratio R is connected to the elementary
absorption cross sections by inserting the numbers of
nucleon pairs and the Clebsch-Gordan Coefficients as
below,
R o(x+. pp) / o(x+, pn)= [<11 10 I 11>2 N1,0 011+ <11 00 I 11>2 NO,O 001
I [ < 11 1 -1 I 10>2 N 1 , - 1 011+ <111-11 QO>2N1,-1010]=== o( x+ +pn[T=O,l] ~ pp[T=l] )= ( 112011 + 3 001 ) I (112011 + 113 010 )
here, oi,f shows the elementary cross section forabsorbing a pion on a nucleon pair with initial isospin
T i and final isospin T f. Ni,j shows the number ofnucleon pairs in 4He with isospin T i and Tz = j.
Same as above. we can get the ratio RD o[4He(x+,pp)] I o[D(3t+, pp»). Assuming that the 001 is givenby the cross section on Deuteron. the elementary cross
011 + (10) /section ratio TIO = o(T=l) I o(T=O)
001 is obtained from R.
Consequently. our preliminary ratio R indicates thatthe contribution of T 1 pair absorption is by a few
times to one order stronger than that of T = O. In order
to confirm the resonance effect and to obtain the
difference between the elementary cross section 001 andthat of Deuteron. the measurements of the pion energy
dependence of the absorption cross sections, on- and offresonance. and the measurements of x+ and xabsorption cross section should follow.

=

=

=
=

=(

=

References
1) S.Mukhopadhyay et al.: Phys. Rev., C43, 957 (1991).
2) L.C.Smith et al.: Few Body XIII, Adelaide, Australia,
Jan.6-11, 1992.
3) H.J.Weyer: Phys. Rep., 195, 295(1990), and references
therein.
4) M.Akemoto et al. : Phys. Lett, 149B, 321(1984).

I o( jt+ +nn[T=I] ~ pn[T=O,I] )* 1 Institute of Physics, University of Tsukuba.
*2 Nuclear Research Center, University of Alberta,
TRIUMF and Institute for Nuclear Study, University ofTokyo(INS).
*3 Laboratory of Nuclear Science, Tohoku University.
*4 INS.
*5 Institute for Nuclear Research, Academy of Science(INR) and INS.
*6 Department of Physics and laboratory of Nuclear
Science, Massachusetts Institute of Technology(MIT).

-16-

RIKEN Accel. Prog. Rep. 26 (1992)

III -1-9. 12C (12 C 12N) 12B Charge-Exchange Reaction at E/ A = 135 MeV
I

T. Ichihara, Y. Fuchi, K. Hatanaka, M. Hosaka, S. Ishida, S. Kato, H. Kawashima,
S. Kubono, S. Miyamoto, T. Niizeki, H. Ohnuma, H. Okamura, H. Orihara,
N. Sakamoto, Y. Tajima, S. Takaku, M.H. Tanaka, H. Toyokawa,T. Yamamoto, M. Yosoi, and M. Ishihara[NUCLEAR REACTION 12C( 12C, 12N)12B, E/A=135 MeV.]
Heavy-ion charge-exchange reaction has been expected
to be used as a new probe for studying spin-isosipn
excitations of nuclei. However, in the E/A < 50 MeV
region, the reaction mechanism is complex and thesuccessive nucleon transfer process is dominant. Onestep and two-step DWBA calculations show that in the
E/A >100 MeV region, the two step process becomes
negligible and the direct charge-exchange is safely
dominant. 1,2)
Charge-exchange reaction of 12C(12C,12N)12B has
beam measured at E/A= 135 Me V using the highresolution spectrograph SMART in RIKEN. 3) Figure 1
shows the typical spectra. The overall energy resolution
was 700 ke V FWHM. Figure 2 shows the measured
differential cross sections of the 12C(12C,12N)12B for
the 12B (1 +) ground state in closed circles.
Microscopic one-step DWBA calculations were
performed using the code of Lenske et al. 1) First,
single particle wave functions of 12C were calculated toreproduce the binding energy of orbits using a WoodSaxon potential. Then transition densities for bothtarget and projectile were constructed with the one-bodytransition amplitude of Winfield et al. Form factors
were then calculated by folding the nucleon-nucleon
effective interactions of Franey and Love. Single
nucleon knock-out exchange contributions in the local
momentum approximation and direct tensor term areincluded. The optical potentials were taken from 12C +12C elastic scattering at 84 Me V/ A.
The solid curve in Fig. 2 shows the result of the
DWBA predictions. The normalization factor for the
calculated cross sections is 0.9 and this is very close tounity. An excellent fit has been obtained for all theangle region. The dotted and dashed curves in Fig.2
show the L=O component and L=2 component,
respectively. The dot-dashed curve in Fig.2 shows the
DWBA calculation using only the central part of thenucleon-nucleon effective interaction (without tensor
interaction). As noticed by these calculations, L=O
component is mainly excited by the central part of theeffective interaction, while L=2 component is mainly
excited by the tensor part of the effective interaction.
The experiment and analysis of the 12C(12C,12N)12B
charge-exchange reaction at E/A= 135 MeV show thatthe cross sections for the L\J1t= 1 + transition can bequantitatively reproduced by the one-step DWBA
calculation using the realistic nucleon-nucleon effective
interaction. This suggests that the heavy-ion chargeexchange reactions in this energy region is a good
spectroscopic tool for nuclear spin-isospin excitations.

-17-

80

oj

aD

.....

60

>-Ql
~
~

..j-

a>

E/A =1 35MeV

>-Ql
;::;l

8 1ab = 0°-0.2°

co

,

r-:

N

'....

,~

40

12C( 12C , 12N) 128

20

r:::::
r:::::

ro.r:::::ou...........
Ul

500

550

600

650

500

550

600
Channel650~

r:::::
~

o
u 150

100

50

o

Fig.I. ObseIVed Spectra for 12C(12C,12N)12B reaction.
10 1
12C( 12 C, 12N) 12B

r:::::.~~

E/ A= 135MeV

10- 1

()
Q)

Ul
Ul
Ul

o

I..
()

o

2

4

6

8

10

eem (deg)
Fig.2.

Obsexved angular distributions.

References
1) H. Lenske et. al.: Phys. Rev. Lett.,62,1457 (1989).
2) N. Anantaraman et al.: Phys. Rev·"C44, 398 (1991).
3) T. Ichihara et. al.: submitted to Phys. Lett. B.

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-10. Deuteron Breakup Reaction at Intermediate Energies
H. Okamura, K. Hatanaka, T. Ichihara, S. Ishida, T. Niizeki, H. Ohnuma, H. Otsu,
H. Sakai, N. Sakamoto, Y. Tajima, H. Toyokawa, T. Uesaka, T. Wakasa, and M. Yosoi[NUCLEAR REACTION 12C, 28Si, 40Ca, 90Zr, 118Sn, 165Ho, 208Pb(d,pn) Ed = 140,270 MeV.]

The breakup of the deuteron is a simple but
fundamental process and has been the subjectof extensive investigations. Kinematically complete measurements have provided valuable information on this problem, although there exists no data above 100 MeV. The RIKEN Ring
Cyclotron can accelerate the deuteron beam up
to 270 MeV and gives us opportunities to shedlight on the possible new aspect of the breakup
reaction.
Our special interest is the mechanism of the
Coulomb breakup at intermediate energies. In
our previous study at 56 MeV,l) a conspicuous double-peaked structure was observed in the
triple differential cross section d3 (J / dnpdnndEp
for the (d, pn) elastic breakup at Op = On =0°. It turned out to be clear evidence for the
Coulomb breakup of the deuteron. The strong
effect of the Coulomb distortion was also observed as the characteristic target-dependence ofthe cross section and as the asymmetric shapeof the double-peaked structure. This effect is
expected to be small at intermediate energies.
We have studied the (d, pn) elastic breakup reaction on 12C , 28Si , 40Ca, 90Z r , 118Sn ,165Ho and
208Pb at Ed = 140 and 270 MeV. Protons weredetected by the SMART spectrograph system 2)
and neutrons were detected by 6 sets of NE213
liquid scintillation counters. The flight path
length of neutron was 22 (12) m for Ed = 270(140) MeV. The resolution of Ep + En was 2.2
Me V FWHM or better depending on the target. The detection efficiency of neutron wascalibrated by using the 7Li(p, n) 7Be reaction at
Ep = 135 and 70 MeV. 3 ) The proton beam was
obtained by acceleratingwith the same magnetic field of cyclotron as that for the deuteronbeam just before the breakup experiment. The
optics property of the SMART spectrograph was
also studied by using protons elastically scattered from a gold target.
The (d, 2 He) and (d, ds=o) reactions as well as
the (d, nX) and (d, pX) inclusive breakup reactions were also measured simultaneously.
Figure 1 shows the triple differential cross section for the 12C, 40Ca, 90Zr and 208Pb targets at

Ht

-18-

Ed = 270 MeV. The energy-integrated double
differential cross section d 2 (J / dnpdf!n has thetarget dependence of Z1.78 and clearly indicatesthe dominance of the Coulomb breakup process. The inclusive (d, nX) reaction, on theother hand, exhibits the target dependence ofAO.61 .

A( d .pn )Agnd.
Etl -2701leV
10000

8,,=8,,=0·

6000

o
2000

1000

o
750

500
250

o t--.......r;;.---75

50
25
OL&....&..................................~......................................................~

100

120

WO

160

180

Proton Energy [MeV]Fig. 1. Triple differential cross sections for 12C,
40Ca, 90Z r and 208Pb at Ed =~ 270 MeV.
References
1) H. Okamura et al.: Contribution to 7th Int.
Conf. on Polarization Phenomena in Nuclear
Physics, Paris (1990).
2) H. Okamura et al.: RIKEN Accel. Prog.
Rep., 25, 128 (1991) and references therein.
3) T.N. Taddeucd et al.: Phys. Rev., C41,
2548 (1990).

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-11. Coulomb Breakup of 8B
T. Motobayashi, M. Gai, N. Iwasa, Y. Ando, Th. Delbar, R.H. France III,K. Furutaka, Y. Futami, K.1. Hahn, N. Inabe, M. Ishihara, T. Kubo,
M. Kurokawa, H. Murakami, T. Nakamura, J. Ruan(Gen), S. Shimoura,
S. Shira to, T. Teranishi, Y. Watanabe, and Z. Zhao
NUCLEARREACTION 208Pb(8B,7Bep)208Pb, E/A=47MeV;][ measured coincidence a( 0).
The 7Be(p,y)8B reaction was studied throughthe 8B breakup process in the Coulomb field of
208Pb. The Coulomb breakup process
8B--7 7Be+p can s~mulate the photo-absorption

reaction 8B(y,p )7Be, the inverse reaction of
7Be(p,y)8B. The (p,y) reaction on 8B is the
major process producing solar neutrinos
observed in the experiments of Davis et al. 1)
and Kamiokande,2) where the observed flux
was 1/3 to 1/2 of the that expected in thestandard solar model. A possible explanation isdue to the neutrino oscillation, but it failed toreproduce the recent results of SAGE andGallex experiments with lower energy
threshold. 3)
The calculation of the high-energy neutrino
flux is based on the 7Be(p;y)8B cross section,
which has been studied in many experiments.
The astrophysical S-factor used in the calculation is S(0)=0.0238±O.OO23 ke V-b, which is aweighted mean of the experimental data.
Recently, Barker and Spear 4) pointed out
possible uncertainties in above determination of
S(O). New measurements with independent
methods are highly desirable. We performed
the present Coulomb breakup experiment assuch a measurement.
A 8B beam of about 47 A MeV was provided-19 -by the RIPS facility of RIKEN Ring Cyclotron.
The breakup products, 7Be and ,proton, weredetected in coincidence by LlE-E telescopes ofplastic scintillators set 5 m from the target. The
particle identification was achieved by the E andtime-of-flight (TOF) information as well as the
LlE-E method. The energies of the proton and
7Be were determined by the TOF obtained by
the signals from the telescopes and the cyclotron RF signal. A helium-bag was set between
the target and hodoscopes to reduce the probability of parasitic reactions.
Since the product 7Be has its excited state at
Eex=429 keY (1/2-), the breakup process feeding this state is possible. To evaluate the crosssection of this process, a BaF2 scintillator array with 60 crystals detected the 'Y -rays emitted
from the excited 7Be. Analysis is now in progress.
References
1) R. Davis: Workshop on Neutrino Telescopes, ed.
M. Baldo-Ceolin, Palazzo Lorendan, Venice, p. 1

(1990) .
2) M. Mori: ibid" p. 61.
3) J.E Wilkerson: 1992 Annual Fall Meet of APS,
Santa Fe, p. 1297(1992); W. Hampel, ibid.,p. 1297.
4) EC. Barker and R.H. Spear: Astrophys. J., 307,

847 (1986),

RIKEN Accel. Prog. Rep. 26 (1992)

III -1-12. Sub-barrier Fusion with Unstable

Neutron-rich Nuclear Beams
A.Yoshida, T.Fukuda, T.Sekine, Y.Watanabe, K.Kimura, H.Okuno, H.Ueno,
Y.Mizoi, H.lzumi, M.Tanikawa, K.Asahi, M.Ishihara, I.Nomura, S.Shimoura,
T.Nakamura, T.Kubo, and H.I.Kim[Sub-barrier fusion, neutron-rich beam reaction.]
Recently, it has been argued that the use of aneutron-rich beam is of great advantage to reachthe super heavy element region. However thefeasibility depends upon the cross section that
we can actually expect for fusion reaction,
especially regarding the sub-barrier fusioncross section.
A large dUmber of data concerning subbarrier fusion using beams of stable nuclei
show an enhancement as compared with theestimations using an one-dimensional barrier
penetration model .1) On the other hand, it isargued that an extremely neutron-rich nucleus
may be dynamically polarized in thecollision(soft E1-dipole mode) and excess
neutrons may be transferred easily to the target
nucleus, thus facilitating fusion. But this typeof experiment has not yet been done, so we
tried, for the first time, to measure the fusioncross section of the unstable neutron-richisotope 29 Al plus Au system.
The ex~eriment was done by using the RIPS,
where 2 Al was produced by bombarding
95Me V lu Ar beams on a Be production target
and separated, and after secondary focus
position(F2), the energy of 29 Al was reduced
to 5Me V lu by using an AI-energy degrader
plate. Then the low energy 29 Al beam wasagain focused at the third focus position(F3)where the secondary reaction Au targets werelocated. To gain a reaction yield, we used amulti-target system comprised of a stack of 22
thin Au foils(170ug/cm 2 each). In the 29 AI+Au
reaction, almost 100% of compound nucleus
will decay by fission. Fission fragments were
measured by two sets of MWPC positioned
both left and right relative to the Au target,-~r-' ~-.':- . ::wt;:
iso-but!::g:::~: 1 I III ~AUtargets._ -.

29 Al Beam+--- ---- - - - -- - - -_

o

IOcm

Fig. 1. The schematic view of secondary reaction target position. A stackof 22 thin Au foil targets is sorounded by two sets of MWPC.

stack(Fig.1 ).
We picked up the fusion-fission event byselecting 4-plane wire coincidence events, andknew the reaction target position by tracing thefission fragment track. Each 29 Al beam energy
was measured by the TOF method between F2and F3(6.2m), and the energy loss in each Au
foil and filled gas was corrected for.
By using information on the deposit energy

and hit pattern of MWPC, we could clearly .
distinguish the fusion-fission events from 29 Al
elastic scattering and transfer-like light particle
emission events. The analysis is now inprogress. Experiments with more neutron rich
Al isotopes will follow.
References
1) P.H. Stelson: Phys.Lett., B205,190(1988).

-20-

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-13. Measurements of llLi + p and 9Li + P Elastic
Scatterings at 60 MeV
C.-B. Moon, M. Fujimaki, S. Hirenzaki, N. Inabe, K. Katori, J.C. Kim,* Y.K. Kim,*
T. Kobayashi, T. Kubo, H. Kumagai, S. Shimoura, T. Suzuki, and I. Tanihata[Inverse reactions, elastic scatterings, phenomenological optical model.]Proton elastic scattering from neutron richnuclei 9Li and llLi have been measured for the
first time at Elab/A = 60 and 62 MeV,
respectively, under the inverse kinematicalconditions. 1)
While the angular distribution of 9Li scattering
follows the systematic trend from those of 6Li
and 7Li scatterings, the 11 Li cross section issmaller by factor of about two.
To understand the measured elastic crosssections, we applied a phenomenological
optical model with the standard potential UN
represented as follows,

more detailed microscopic studies that include
the reaction mechanisms, such as a break upprocess, due to loosely bound neutrons in 11 Li.

t: data... : potential A-: potential B

UN = -VRfR - lWyfI + 4iaI W S(d/dr)fI +2(Nmne)21/r(r/dr)V sofso(L·S) + Vcoul
with Ri=riAI/3, fi=[l+exp{(r-Ri)/aj}J-l, i = R,I
and SO, where subscripts R, I, and SO denote
real, imaginary, and spin -orbit, respectively.
This phenomenological optical potential model
fit to the 11 Li suggests that both the real and theimaginary potentials should be considerably
modified from the global fit parameters that
reproduce the proton elastic scatterings from theother Li isotopes, 6Li, 7Li, and also 9Li. The
best fit as shown by the solid curve in Fig.1
was obtained with a combination of a shallow
real potential and an imaginary potential with along tail. The dotted curve in Fig.1, on theother hand, is the fit result as obtained by fixing
the depth of the real potential as the global
parameters of 7Li. It should be emphasized thatthe reaction cross section predicted by thispotential, 456 mb, is somewhat larger than theestimated empirical value of 359 - 414 mb.
To understand the present 11 Li data, we need

20

40

60

80

8 CM (deg)Fig. 1. Elastic scattering angular distribution for the
11 Li + P system at Elat/A = 62 MeV. The dotted andthe solid curves are the fits by the optical model
calculations with the ' potential A and B described
below, respectively. Parameters corresponding to thepotential A (B) are, in the usual notation where depths
are in MeV and lengths are in fm, as follows ; VR =35.96 (18.06), rR =1.13 (1.385), aR = 0.69 (0.546),
Wy = 6.64 (4.26), Ws = 4.58 (4.60), q = 1.11 (0.56),
aI = 0.81 (1.16), VSO = 5.9 (5.9), rso = 0.8 (0.8),
aso = 0.63 (0.63). The calculated reaction crosssections are 456 and 388 mb, respectively.
References
1) C.-B. Moon et ai. : Phys. Lett., B 297, 39 (1992).

* Seoul National University, Korea.
-21-

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-14. Coulomb Dissociation of llLi on a Lead Target at 43 A MeV
S. Shimoura, N. Inabe, M. Ishihara, T. Kobayashi, T. Kubo,
T. Nakamura, R.H. Siemssen,* 1. Tailihata, and Y. Watanabe
NUCLEAR REACTIONS heavy-ion collision, radio]
active beam, Coulomb dissociation, Pb(l1 Li, 9Li + 2n)X,[ soft E1 mode.
The Coulomb dissociation reaction of 11 Li nucleus, Pb(l1 Li,9Li+2n)X, was measured at anincident energy of 43 A MeV. Secondary beamsof 11Li were produced at the RIPS using thefragmentation of 100 A MeV 18 0 beams on a
Be target. The experimental setup and method
are presented elsewhere. 1 )Figure 1 shows an excitation energy spectrumof 11 Li* obtained by making an invariant mass ofthe observed three-body system (9Li+2n) eventby-event. The peak position and the average ofthe spectrum are 1 MeV and 1.9 MeV, respectively. Because of the dominace of E1 excitationin the Coulomb dissociation reaction, the peakindicate a notable E1 strength in the excitationof the 11 Li nucleus, which is suggested in Refs.
2 and 3.
A relative energy spectrum between two neutrons coincident with 9Li is shown in Fig. 2,
whose average is 0.3 MeV. This indicates thatthe excitation is dominated by the relative motion of 9Li and the center-of-mass of 2n systemrather than that of two neutrons, which is consistent with the picture of an oscillation between
the core and the neutron halo. This spectrum ismuch sharper than the prediction based on the
Migdal-Watson model describing a final state interaction (FSI) between two neutrons. This may
indicate the distance between the two neutrons
is too large to make FSI.
The present work is supported by the Grantin-Aid for Scientific Research (No. 0242005) by
the Ministry of Education, Culture and Scienceof Japan.

150-....'§

I

..
~b
"d

I-

100

I-

75

l-

50

t-

25

I- •

0

I

-

125

+++++
+

.0

$

I

I

t

+

I

!

-

+++

-

+
+++++

I

I + ++I· ..-

I

2

0

-

3

Ex (MeV)45Fig. 1. Excitation energy spectrum of 11 Li nucleus
deduced from invariant mass of 9Li+2n system.
200

=:
§

150

.0

$

Tfl j

100

c:I
I
c:I

~

t;-

1111111

50

+ +H+

"d

o

+++++++.+
o

0.2

0.4

0.6

0.8

En - n (MeV)

Fig. 2. Relative energy spectrum between two neutrons. Solid line represents the shape of the density of state in terms of the Migdal-Watson model.

References
1) S. Shimoura et al.: 6th Int. Con! on Nuclei farfrom Stability, Bernkastel-Kues, July, 1992.
2) T. Kobayashi et al.: Phys. Lett., 232B, 51(1989).
3) R. Anne et al.: ibid., 250B, 1219 (1990).

* KVI, Groningen, the Netherland.
-22-

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-15. Mass Measurements of Neutron-Rich Unbound Nuclei
by Break-Up Reactions
T. Teranishi, K. Abe, N. Aoi, Y. Doki, M. Fujimaki, N. Inabe, N. Iwasa,
K. Katori, T. Kobayashi, T. Kubo, T. Nakamura, H. Okuno, S. Shimoura,
T. Suzuki, I. Tanihata, Y . Watanabe, A. Yoshida, and M.Ishihara[NUCLEAR REACTIONS, heavy-ion collision, radioactive nuclear beam, C(8He,7He)X.]

Recent development of radioactive beams has
opened a wide domain of unstable nuclei to bestudied. One of the interesting subjects is determination of masses of these nuclei. This paper reports on an attempt to develop a new
method of mass determination by means of nuclear reactions. The method is, in particular,
useful for particle-unbound nuclei, therefore,
nuclei beyond the drip lines.
A classical method using nuclear reactions is a
missing mass method, where the Q value ismeasured in a binary reaction between stable
nuclei. The method usually provides a goodmass resolution, but is limited in the range of
unstable nuclei to be reached.
In the present method for particle-unboundnuclei, we use the "invariant-mass" technique,where particles in the final state are detected andtheir momentum vectors are used to construct
the invariant mass of the intermediate state. The
mass resolution is insensitive to the resolutionof the incident energy. Any types of reactions
may be used to populate the state. In addition
the range of accessible nuclei may be enlarged
using radioactive beams. In the present case,neutron-unbound 5He, 7He, and lOLi nuclei
were studied in the break-up processes of 6He,
8He, and 11 Li projectiles. Known masses of
5He and 7He were studied to examine themethod with radioactive beams.
The secondary beams of energy 72A MeV
were provided from the radioactive beam line
(RIPS) using a 100A MeV 180 primary beam
onto a Be target. The secondary projectile wasprojected on C and Pb targets and was broken
into one charged particle and two neutrons. The
detector system consisted of neutron counters
and a magnetic spectrometer, which covered
nearly 41t solid angle in the projectile frame.
Figure 1 shows preliminary results on the
6He+n system. Figure lea) shows a scatter plotof the relative momentum (P) between 6He andneutron in the x-y plane perpendicular to thebeam direction z. Events with pz=O are plotted.

(a)

(b)

... ...

II

·60

125

~

~

~
'U

·40

·20

0

20

40

10

10

px[MeV/c]

100

75

I

V

I

:;:: 50

1+
11.-

25

0.5

1.5

1

Ere!

[MeV]

Fig.I. (a) Cross-sectional view of the 6He-n relative momentum distribution at pz=O in C+8He -> 6He+n+X reaction. (b) 6He-n relative energy spectrum.

The circular distribution of the events is consistent with the decay of a resonance state. Figure1(b) shows a relative energy spectrum for the
6He-n system. Events over the whole measured
phase space are included. A dominant peak appears at 350 keY, which is roughly consistent
with but smaller than a previous result 1) of
440±30 keY. The source of the slight difference is not understood yet. Examinations arestill under progress to understood it. The apparent width (480 keV (FWHM)) observed iswidened as compared to the known value of
r=170 keY, indicating the mass resolution of
450 keV (FWHM) of the present experiment.
The analysis on 4He+n and 9Li+n systems isin progress.
References
1) Richard H. Stokes and P. O. Young: Phys. Rev., 178,2024 (1969).

-23-

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-16. Momentum Distribution of Projectile-Rapidity Neutrons
from 6,8He, 9,llLi Projectiles at 800 and 72 MeV/nucleon
T. Kobayashi, K. Yoshida, I. Tanihata, K. Matsuta, T. Minamisono, K. Sugimoto,S. Shimoura, D. Olson, * H. Wieman, * W. Christie, *Y Watanabe, T. Nakamura, M. Ishihara, T. Teranishi, and N. Iwasa
NUClEAR REACfIONS C,Pb~,8He,4,6He+D+x}, C,Pb(9,11Li,7,8,9r..i+D+x) ][ EIA=800 and 72MeV; measured momentum distribution do/dp.

Projectile fragmentation is one of the experimental
methods to study the properties of nuclei far fromstability. Although the reaction mechanism is believed
to be simple due to its peripheral nature, the effect of thefragmentation mechanism for extracting the nuclear
structure infonnation from the experimental data is notclear. We have systematically studied the momentum
distribution (MD) of projectile fragments and neutronsin coincidence for few-neutron-removal processes from
6,8He and 9,IILi projectiles on C and Pb targets. 1)
Measurements were performed at two incident energies:
800 MeV/nucleon (LBL Bevalac) and 72 MeV/nucleon(Riken Ring Cyclotron).
The MD of neutrons in coincidence with 4,6He and
9Li from 6,8He and llLi at 800 MeV/nucleon showed
two-Gaussian structure.
The width of the narrowcomponent is shown in Fig.1 as a function of theseparation energy of valence neutrons. The dashed line
in Fig.l is from a simple model assuming the sudden
approximation and no correlation between valence
neutrons. Apparently, this model does not explain thegeneral tendency, especially for neutrons from 8He and9Li. If one neutron is removed from the projectile, theintermediate state, such as 5, 7He or 10Li, is unstableagainst neutron emission. Therefore, the sequential
decay mechanism via such an intennediate state can beimportant.
The solid line in Fig.l is an estimate
assuming the sequential decay mechanism, andreproduces the general tendency.
This is a firstexperimental indication that the sequential decay
mechanism is important even for the two-neutronremoval process from neutron-rich nuclei.
The width of the neutron MD in coincidence with 9Li
from llLi is shown in Fig.2 together with the GANIL
data2) for studying the dependence on incident-energy andtarget. The systematics showed two features: (1) targetindependence, and (2) slight incident-energy dependence.
The latter might result from probing the density
distribution of 11 Li at a different radius due to a different
nucleon-nucleon cross section: we need morequantitative estimate.

* LBL, Berkeley, USA.
-24-

100
,,;
,,;
,,;
,,;
,,;

60

~

~
~ 60

,,;

'" '"

,,;,,; Sudden Approx.
/

:5'tl

/
/

.~

~

'"

'"
'" '"

,,;

/

6 He /

40

/

/

/--

8He

9U

~.--~--~~---------+

20

Sequential Decay

llLi
0

2 4 6
S2n [MeV]

0

Fig. 1. The momentum width of neutrons for the twoneutron-removal process ftom 6,8He and 9,11 Li
projectiles on a C target as a function of the separationenergy of valence neutrons.

•

30

n PT 800MeV/ A LBL

• n
() n

P p 7211eV/ A Riken
PT 29UeV/ A Ganil+--+f---t--t----J~ ······ · ·· · · .. ·· · ··· t ··· ·· · ····

°5~wulLO--~~~~50~~lWO-0--~~~500

Target Mass [amu]Fig. 2. The width of the neutron momentum distribution forthe (llLi,9Li) reaction on various targets at 29, 72, and
800 MeV/A.

References
1) T. Kobayashi: Nucl. Phys., A (1992) in press.
2) R. Anne et al.: Phys. Lett., B 250, 19 (1990).

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-17. Revelation of Thick Neutron Skins in Nuclei t
I. Tanihata, D. Hirata, T. Kobayashi, S. Shimoura, K. Sugimoto, * and H. Toki
[Exotic nuclei, neutron skin, nuclear reaction, radioactive nuclear beam.]
In spite of detailed studies of stable nuclei ofa large neutron excess (N - Z), no evidence of a
thick neutron skin had been observed. For
example, the root-mean-square (rms) radius of
the neutron distribution is larger than that of the
protons only by -0.2 fm in 48Ca (N-Z = 8) and by-0.15 fm for 208pb (N-Z = 44).
Recently a development of high-energy
radioactive nuclear beams enabled us todetermine nuclear radii of ~-unstable neutron-richnuclei in which one may expect thick neutron
skins due not only to the neutron excess but also to
the large difference between the neutron and theproton Fermi energies. Nuclear matter radii oflight nuclei were determined by measurements of
the interaction cross sections (aI).1) Althoughthese measurements provided the determinationsof the matter radii, the neutron and the proton
radii were not determined separately before.
Using the relations between the interaction
cross sections and the neutron removal crosssections, thick neutron skins have been found out
in 6He and 8He nuclei. Observed relations,andaI(6He)-aI(4He) = a_2n(6He)
aI(8He)-aI(4He) = a-2n(8He)-a-4n(8He),
between interaction cross sections (aO andfragmentation cross sections (a_2nl a_4n) 2)
indicate that the 4He core in 6He (or 8He) has
same density distribution as 4He nucleus) Then
we used the harmonic oscillator density
distributions to fit the aI's using Glaubercalculation under the constraint that core 4He is
fixed. We found following differences:<r2 n>I/2-<r2 >1/2 =0.87fm for 6He and<r2n>1I2 - <!p>l12 = 0.93 fm for 8He.
To study other possibilities of neutron skinformations, we applied the relativistic mean

field (RMF) theory to many isotopes. 4) We haveanalyzed the behavior of~r = <r2 n>I/2 - <r2p>1/2
against the AEF= EFn - EFp (Difference of Fermi
energies of proton and neutron). We found a linear
relation between those differences as shown in
Fig. 1. The differences;<r2n>I/2-<r2p>1/2 = 0.98 fm for 6He
and<r2n>1/2_<r2p>1/2 =1.1 fmfor 8He
are in good agreement with the experimental
results shown above. The calculated proton radii
are in good agreement with experimental data
and the neutron skin of 0.75 fm is predicted for
31Na.

&-

[fm]_
1.0

0.5

-

0.0
I

-0.5
-20

o

20

I

~EF [MeV]

Fig. 1. The difference between the rms radius fromneutrons and protons as a function of the difference
between the Fermi energies of neutrons andprotons for several isotopes.

References'1) I. Tanihata, et al.: Phys. Lett., 160B, 380 (1985)~ I.
Tanihata, et al.: Phys. Rev. Lett., 55, 2676 (l985)~ I.
Tanihata, et a!.: Phys. Lett., B206, 592 (1988).
2) T. Kobayashi, et al.: Phys. Rev. Lett., 60, 2599 (1988).

3) Y. Ogawa, K. Yabana, and Y. Suzuki: Nucl. Phys., inpress.
4) D. Hirata, et al.: Phys. Rev., C44, 1467 (1991).

t Condensed from the article in Phys. Lett., B289, 261(1992).

* Fac. Sci., Osaka Univ.
-25-

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-18. g-Factor Measurement of 21F Ground State
H. Okuno, H. Veno, K. Asahi, M. Ishihara, T. Nakamura, M. Adachi, H. Sato,
H. Izumi, T. Sekine, N. Inabe, T. Kubo, A. Yoshida, T. Shimoda,
H. Miyatake, and N. Takahashi
NUCLEAR REACfION 93Nb + 22Ne, E/A = 70 MeV/nucleon ; measured ~-ray asymmetry of 20p and 21p, nuclear[
magnetic resonance; deduced g-factor of 2lp ground state.
Recent experiments I) have revealed that ejectile
nuclei in the fragmentation of intermediateenergy heavy-ions are largely spin-polarized.
Previously,2) we reported the application of thisphenomenon, resulting in the firstmeasurements of the ground-state g-factors of. hiel' 14B and ISB . ''11.
•
neutron-nc
nuc
yye present, In
this report, the extension of the measurement to
the g-factor of 21F (Tl/2 = 4.32 s). The 2lF is a
nucleus rather close to the stability but its gfactor had not been measured before.
The experiment was carried out by using aradioactive beam line RIPS. 3) Short lived nuclei
20p and 21F were produced by fragmentation of
22Ne projectiles at 70 Me V/nucleon on a 93Nb
target (300 ~m in thickness). Those nuclei
which were emitted at angles around 2.5
degrees were isotope-separated andmomentum-selected by the RIPS and implanted
into a CaP crystal placed at the final focus of
the RIPS as shown in Fig. 1. The g-factor was
deduced from the frequency of NMR detectedby the change of ~-ray asymmetry. The NMR

J

spectrum finally obtained is shown in Fig. 2.
The g-factor of Wp, which was already knownwith good accuracy, was used for thecalibration. Prom the peak position extracted
from the least-squares fitting, we obtained theg-value as g( ZIp) = 1.57 ± 0.02.
The experimental value agrees well with the gfactor for the 1tds/2 configuration, 1.58, byassuming a spin-quenching factor of 0.7. The
experimental value is in fair agreement with theg-factor, 1.52, obtained from a shell model
calculation4) using OXBASH code. S)

2.03

0

...,

2 .02

Q

.......
:J

2.01

2.00

g = 1.57 ± 0.02
frequency (kHz)UP

magnet poleFig. 2. Nuclear magnetic resonance spectrum of 21p'
Up/down ratios of J3-rays emitted from 21p are plotted
as a function of the rf-frequency.

collimator

\

1

b

~ plastic scintillators~r~ e--"mr!tn~~ '-[r'-'~~-",;~~~

References

fstaticlield .. - . plastic scintillators~lenergy degrader(Cu)
rfcoil................

DOWN

r

magnet poleFig. 1. Schematic diagram of the NMR apparatus at the
final focus of the RIPS.

1) K. Asahi et at.: Phys. Lett., B 2S 1,488 (1990).
2) H. Okuno et at.: RlKEN Accel. Prog. Rep., 24, 14(1990).
3) T. Kubo et at.: Proc. 1st lnt. Conf. on Radioactive
Nuclear Beams 1989 Berkeley, p.563 (1990).
4) B. A. Brown: OXBASH user's manual.
1985. unpublished.
5) T. Otsuka et al.: private communication.

- 26-

RIKEN Accel. Prog . Rep. 26 (1992)

111-1-19. Spin Polarization of 43Ti Fragment from 116 A MeV
46Ti Beam
K. Matsuta,* A. Ozawa, T. Minamisono, Y. Nojiri,* M. Fukuda, A. Kitagawa,*
T. Ohtsubo,* S. Mornota,* S. Fukuda,* K. Sugirnoto,* I. Tanihata, K. Yoshida,
K. Ornata, 1. R. Alonso,** G. F. Krebs,** and T. 1. M. Syrnons**
NUCLEAR REACTION 197Au, 12C+ 4&Yi, E= 116 A MeV; measured][ J3-ray asymmetry of 43Ti nucleus; deduced spin polarization of 43Ti.
A 116 A MeV 46Ti beam was used to bombard Au
and C targets. Spin polarization as well as angular
distribution of 43Ti fragments were measured at forward
angles (9-20 ). These measurements were performed at
the LBL's Bevalac. The experimental setup was
essentially the same as the one used in a previous
work.!)
Observed angular distributions were broader than thosepredicted on the basis of the Goldhaber model 2 )although the model explained the widths of the
momentum distributions quite well.
This is acharacteristic feature of the projectile fragmentation
process in the present energy region, as shown by Van
Bibber et al. 3) For comprehension of the broadening,
nuclear spin polarization of the fragments is the best
observable. It reflects the sign of the scattering angle
by changing its sign depending upon whether positiveor negative angle scattering dominates in the reaction.4)
The momentum dependence of the polarization
observed for the case of a C target is shown in Fig.1.
Although the dependence observed for the case of an Au
target was essentially the same as the one reported for
39Ca and 37K fragments in the 40Ca on Au collision, 1)
the dependence was reversed in the case of a C target. It
was concluded from the measurements that positive
angle scattering dominates in the case of an Au target
and negative angle scattering dominates in the case of a
C target. This result strongly suggests that orbital
deflection of the projectile is caused by the Coulomb
potential in the case of an Au target and by the nuclear
potential in the case of a C target prior to the breakup.
Even in the present energy region, these potentials play
an important role and cause the broadening of theangular distributions of the fragments.
This work was partly supported by the Grant-in-Aid
for Scientific Research Program from The Ministry of
Education, Culture and Science, Japan. Support wasalso given by the USA-Japan Collaborative Research,
given by both the Japan Scientific Foundation and the
National Science Foundation, USA. This work was also
supported in part by the US Department of Energy under
the contract No. DE-AC03-76SF0098.

6

12c(4&ri,43 Ti) 9=1.50

4

E=116AMeV

--.
~

'-'
~

.........0

2

~

.c:N

~

0

~

445

450
Fragment momentum (A MeV/c)

Fig. 1. Momentum dependence of the fragment polarizationof 43Ti. Closed circles are observed polarizations. Opencircles are relative yields of 43 Ti. The momentum
corresp')nding to the beam velocity is shown by thearrow. The solid line represents the polarization
calculated using a simple projectile fragmentation
model 4 ) and multiplied by 1120. Negative angle
scattering and an additional energy-loss (2.5 A MeV/c)were assumed in the calculation.
References
1) K. Matsuta et al: Phys. Lett., B 281, 214 (1992).
2) A.S. Goldhaber: Phys. Lett., B 53, 306 (1974).
3) K. Van Bibber et al: Phys. Rev. Lett., 43, 840 (1979).
4) K. Asahi et al: Phys. Lett., B 251, 488 (1990).

* Osaka Univ.
** LBL, Berkeley, U.S.A.
-27-

RIKEN Accel. Prog. Rep . 26 (1992)

111-1-20. Proton Elastic Scattering with 9Li and llLi
and Its Halo Structures. Hirenzaki, H. Toki, and I. Tanihata[Proton elastic scattering, neutron halo.]
In the study of unstable nuclei, one of the most
exciting findings was the neutron halo around the 9Li
core in 11 Li. The structure and reactions of 11 Li havebeen studied extensively both theoretically andexperimentally. In this report, we study the proton
elastic scattering on 9 Li and 11 Li using the Born
approximation and the optical potential model.1) The
experiment was recently performed at 60 Me V for 9Li
and at 62 Me V for 11 Li at the RING Cyclotron facility
in RIKEN by C.-B. Moon et al. The data for p+6Li
and p+ 7Li also exist at 65 MeV.2) In the angular rangeof 25 to 50 degrees in c.m. system, the data show thatthe cross section of 11 Li is about 70 % of the crosssection of other Li isotopes and the slopes of the crosssections are almost the same for all four isotopes.
First, we study the data of 9Li and 11 Li using theBorn approximation and try to explain qualitatively the
essential features of the data. The important conclusionfrom this qualitative study is that fragile halo neutrons
are responsible to the smaller cross section through theimaginary part of the p+ 11 Li optical potential. We canevaluate the imaginary potential from halo neutrons
using the experimental proton-neutron total crosssection O"pn as follows;V2n(r) = - in;O"pn P2n(r)(1)

where v is the velocity of the incident proton. We findthat V2n(O) = -1.7 i MeV.
We then look for the optical potential parameters
using the experimental data. We assume that 11 Li has
the configuration of 9Li as the core plus two weakly
bound neutrons. We take the optical potential of 9Li as
the basic potential for 11 Li and add a long range
component, which is supposed to arise from the halo
neutrons. The additional optical potential due to halo
neutrons is assumed to have only an imaginary partwhich is justified by the qualitative study within the
Born approximation. We added the halo potential eq. (1)to the potential that is obtained by fitting the 9Li data.
The result is shown in Fig. 1 by the broken line. We
find that the data of p+ 11 Li elastic scattering can be
reproduced qualitatively well, except for the discrepancy
near the dip (45 degree).

10- 1 ~~--~~--~~--~~--~~~
40
20
30
50
60
70
8QJJ[ degree]
Fig. 1. The proton elastic scattering cross sections for 11 Li
as a function of c.m. angle. The broken line is the result
calculated with the core potential fitted to 9Li data plus
the halo potential shown in eq. (1). The solid line shows
the result of the optical model fit obtained by modifying
only the halo potential. The dot-dashed line is the resultof the fit obtained by modifying only the core potential.

We could explain the essential features of the data ofp+ 11 Li scattering by assuming that 11 Li has the halo
structure. We found that the features of the data can beunderstood as the break up effect of halo neutrons of
11 Li which should be taken into account as an
imaginary part of the optical potential. The imaginary
potential of halo is weak because of a low halo neutron
density and a mean free path in this potential is around25 fm for 60 MeV proton. Thus we can think the haloas the "cloudy crystal ball".
References-28-1) S. Hirenzaki, H. Toki, and I. Tanihata: Nucl. Ph)l8.,
A, in press.
2) M. Tosaki: Ph.D. thesis, Osaka Univ. (1989).

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-21. Langevin Approach to Pre-scission Neutron Multiplicities

and Fragment Kinetic Energies
T. Wada, N. Carjan,* and Y. Abe[Langevin equation, pre-scission neutron multiplicity, fragment kinetic energy distribution, one-body dissipation.]
Experimental evidence of fission as a slow process hascome from pre-scission multiplicities of neutrons,
charged particles, and 'Y rays. Hinde et al. l ) observed apre-scission neutron multiplicity much larger than thevalue obtained with a simple statistical model. To analyze the pre-scission neutron data, they had to introduce
a long delay time. The delay time has been interpreted
as a transient time during which the fissioning degree of
freedom attains the quasi-stationary distribution in thephase space. The kinetic energy distribution of fission
fragments is another important observable related to fission dynamics; it is related to the descent from saddle toscission. Recently, realistic calculations were made forthese two physical quantities using the two-dimensional
Langevin equation. 2) However, the transient time is
not a measured quantity but extracted from the pre-scission neutron multiplicity with some assumptions. The
aim of this report is to study fission dynamics consistently from the ground state to scission under continuous cooling due to evaporation of particles and to calculate the neutron multiplicity and the kinetic energy distribution at the same time. Insight into the dissipation
mechanism of nuclear collective motion at high excitation energy will be thus obtained.

Table 1. Calculated results for the cases of the one-body friction and of the two-body viscosity with Jl = 0.20 TP.
The columns contain: the excitation energy (E*(MeV», the fusion cross section (CT/us (mb», the fusion-fission
cross section (CTfos (mb», the fusion-evaporation cross section (CT4!11 (mb», the pre-scission multiplicity of neutron(vpr4!)' proton (npr4!)' a particle (apr4!)' the average total kinetic energy of the fission fragments (TKE (MeV», andthe variance (CTrKE (MeV».

E:
80.7

195.8

I-body2-bodyexpo
I-body2-bodyexpo

O'fltsO'fiss0'4!11

1150
1150
1150
1400
1400
1400

790
817
767
1244
1261

360
333
383
156
139

-

-

We solved a two-dimensional Langevin equation andcalculated the pre-scission multiplicities of neutrons,
protons, and a particles as well as the kinetic energy
distribution of fission fragments. Particle emission was
included in the continuous limit. 3) Temperature dependence of the nuclear surface energy was included as,
Es(q,n = Es(q,T=O) (1 - ~T2).4) Calculations havebeen made for the symmetric fission of 200pb nucleus
since the following reactions have been studied experimentally: 19p+181Ta (E* = 80.7 MeV)5) and 16()+184W(E* = 195.8 MeV).6) The spin distribution of the compound nucleus is determined to reproduce the experimental fusion cross section. We assign an event as fusionevaporation if the corresponding trajectory does not escape before the fission width becomes comparable to the'Y decay width. Calculated results for the wall-and-window one-body dissipation case are given in Table 1.
The value of ~ adopted here is 0.014 MeV-2. It is remarkable that the calculated pre-scission neutron multiplicity (vpr4!) coincides with the experimental one within
the error bar. The fusion-fission cross section is alsoquite well reproduced. As for the kinetic energy distri-Vpr4!

1CDr4!

2.93
2.84
3.2±0.3
7.33
7.03
7.7±O.3

0.00920.01080.363
0.350

a Dr4!
0.00370.0037
0.140
0.137

-

-

TKE

O'TKE

135.1
108.6

8.46
9.92
10.2
. 11.5
16.5

137.0
107.4
139

bution, the calculated mean value (TKE) is in good
agreement with Viola systematics'?) The calculated
variance (O'TKE), however, is too small to reproduce theexperiment at E* = 195.8 MeV. Results with the hydrodynamical two-body viscosity are also given in
Table 1. Unusually strong {j..L = 0.2 TP) two-body viscosity is necessary to reproduce the observed neutron
multiplicity, but TKE is far smaller than Viola systematics with this strong viscosity. A consistent explanation of neutron multiplicities and fragment kinetic energies supports the one-body friction and not the hydrodynamical two-body viscosity. It is, therefore, extremelyinteresting to derive or explain the one-body friction by
microscopic theories.
References
1) D.l Hinde et al.: Nucl.Phys., AS02, 497c (1989).
2) T. Wada et al.: Nud. Phys., AS38, 283c (1992).
3) H. Delagrange et al.: Z. Phys., A323, 437 (1986).
4) X. Campi et al.: Z. Phys., A309, 239 (1983).
5) D.l Hinde et al.: Nucl. Phys., A4S2, 550 (1986).
6) DJ. Hinde et al.: Phys. Rev., C4S, 1229 (1992).
7) V.E. Viola et al.: Phys. Rev., C31, 1550 (1985).

* Centre d'Etudes Nucleaires de Bordeaux, France.
-29-

RIKEN Accel. Prog. Rep . 26 (1992)

111-1-22. Systematics of Isotope Production Rates
Fission Products and Their Barrier Penetration
H. Sato and A. Mizobuchi*[NUCLEAR FISSION fission-product yields.]
In a previous work,l) we showedthat systematics of isotope production rates of the nuclear collision is well expressed by two
different thermalization processes: first fast high energy thermalization and second evaporation.
At low incident energy, especially, the isotope production rate
is found to be expressed bya ( Y)oc

exp (_

My)

T

where T is the temperature parameter, and My is the mass excessof the nucleus Y produced. Here,
we study the relationship between
the experimental mass distribution of fission products and its
mass excesses by employing theabove equation.
As for the mass
excess, we employ the minimum
mass excess Mex for a given mass
number.
Then we find, in manyfissioning nuclei, that the grossshape of the mass distribution
coincides nicely with the distribution of its mass excess with aconstant T except in the gap
region A = 100 - 130.
The caseof 235 U (n,f) fissions with thethermal, 3 MeV, and 14 MeV neutrons 2 ) is shown in Fig. 1.
Thetemperature T of 2.6 MeV obtainedis very close to ones observed in
isotope productions in 24 GeV p-~
and 33.6 GeV 16 0 - Pb collisions. 1
Note: A naive liquid drop model
predicts the symmetric fission,
where the fissioning to equalmass nuclei ( half of the parent
nucleus) is most probable.
Inthe 235U(n,f) fissions, this mostprobable mass number is 118 whichcoincides, "accidentally", wi th
the one that gives the smallest
minimum mass excess. However, if
the incident energy dependence ofthe mass distribution of thesingle fission fragment is taken
into account, the mass excess
dependence of the distribution
seems to be plausible.
We also study the gap shape in
the region A = 100 - 130 in termsof the barrier penetrability generated by the mass formula andthe density distribution generated by the Hartree-Fock type variational calculation with shellmodel correction, and find thatthe shapes are semiquantitatively
understood as the competition ofmany heavy particle decay modes.
-Mex (MeV)

GO

80
78
70
0.001 L.....-----L._--'-_--L--_.L------L_----L_....I...-_..L...--..1.I
70
80
GO
100
110
120
130
140
180

Maaa number A

Fig.1. The fission yields 2 ) and minimum
mass excesses Mex in the 235 V(n,f)
fissions.
Referencesl)H.Sato: Phys.Rev.,C37, 2902 (1988).
2)E.A.C.Crouch: Atomic Data and Nuclear
Data Tables, 19, 419 (1977).

* lnst. for Nucl. Study, Vniv. Tokyo.
-30-

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-23. Nucleus as a Canonical Ensemble: Deformed Nucle:us
H. Sato[NUCLEAR STRUCTURE w, E and thermal properties of deformed nuc1eLJ
In previous works,
we havestudied the nuclear system bothat low and high excitation energies in terms of the canonicalensemble with the employment of
the temperature dependent antisymmetrized many particle density
matrix in a har)onic oscillator(HO) potential. 1
We found that
this ensembie is equivalent to
the ground state of the HO shellmodel at a low temperature limit,
and that various phenomena observed in medium and high energy
nuclear collisions are nicely explainable as the property of thisensemble at high temperatures.
In this work, we extend the study
to the spheroidal symmetric HO
potential,

the level density of the system,
Fig.1 corresponds to the level
densi ty distribution discussed by
Strutinsky in t~e study of fission phen~mena.3
This point is
expected to be seen more clearly,
if a Nilsson type potential isemployed.
Such kind of study is
now in progress.

- lD.D- ZF.D2h=L+ m (<.>2 Z2+(a)2 (x2 +y2) )
2m 2
3.1.
,
=<.> ",1/3 (a) =(a)

6)
.L

0"

I

3

'ft- 2 / 3

0"and 'ft=~'.
3-2a'

where (&)0 is an HO constant forthe spherical one.
Theoreticaltreatments are identical withthose of the spherical case except the unnormalized one particle density matrix. We study the
deformation 8 and particle number
N dependence of thetnternal
energy and the entropy,2
As anexample, the entropy SN calculated with temperature T = 0.25 MeV
is summarized in Fig. 1.
Thepeaks in the entropy at the deformation 0 = -0.75, 0.0, and 0,6
correspondtosimpleintegerratios of the HO constants (&)L and(&)3' Since the entropy relates to

I

.;

:

I

I

OEFDAI1ATIDN

Fig.1 The deformation dependence of theentropy SN at T= 0.25 MeV.
Referencesl)H.Sato: Phys.Rev.,C36, 785 and 794(1987).
2)H. Sato: in Proc. of the Symp. on
Group Theory and Special Symmetries
in Nucl. Phys., p.359 (World Scientific, 1992).
3)V.M.Strutinsky: Nucl.Phys.,A122, 1(1968).

-31-

RIKEN AcceI. Prog. Rep. 26 (1992)

111-1-24. An Application of Multi-precision Arithmetic in Physics
Nucleus as a Canonical Ensemble
H. Sato[NUCLEAR STRUCTURE w, E and thermal properties.]
The study of multi-precision arithmetic has progressed very far
due to an effective usage of ahigh speed computer and a practical study of the capability ofcomputers.
However, except thecalculation of R, its actual applications are scarcely found, in
physics especially. In this work,
we show that multi-precision arithmetic plays an important rolein the study of nuclear physics.
In a previous work,l we studied nuclear thermodynamical quantities in terms of the temperature dependent antisymmetrized
dens i ty rna trices of many fermionsin a harmonic oscillator (HO)well. For a temperature T(=l/S)
and particle number N system withan HO constant ~, the trace ZN ofthe densi ty matrix is found tosatisfy the recurrence relation

multi-precision
arithmetics 2 ):Case(l) a mixture mode of integer
and real numbers wi th a 10 8 a rithmetic, Case(2) a real number
mode with a 10 8 arithmetic, andCase(3) a real number mode with a
10 6 arithmetic with Fast Fourier
Transformation (FFT).3) Figure 1
shows a comparison of calculational times of three cases foreach N.
The calculation is performed with FACOM-M380 at RIKEN.
While this nuclear model is applicable to a wide range of nuclear study, a much faster fully
equiped subroutine package of thearithmetic is eagerly needed.
Time(s)

100

N

ZN=

~E (-1) n+1Hn~ZN_nl

10

•
-

n=l

where Hn~ = Ng/(2sinhtnSh0)3 with
Ng = 2(4) for spin(isospin) formalism, and Zo = 1. With thesetraces, we showed that this ensemble is equivalent to a groundstate of an HO shell model at alow T limit. We also showed therelationship between thermodynamical quantities and the nuclear
level density.
Since the trace ZN behaves likean exp(-SE N) at a low T with thesum of single particle energies
EN' the accuracy of an exp(-aE N)
must be reserved in the calculation of Zl to satisfy the recurrence relation. To study thispoint, we perform three different

Case2
Case3

0.1

0 .0 1 ' - - - - ' - ----'----'--- - ' ----'------''--.l....--'----'----1
o 10 20 30 40 50 60 10 eo 90 100

N

Fig.1. The N dependence of the calculational time in second.
References
1)H.Sato: Phys.Rev.,C36, 785 and 794(1987).
2)D.E.Knuth: SEMINUMERICAL ALGORITHMS
Arithmetic in The Art of Computer
programming, II, Addison-Wesley(1981).
3)H.Hirayama: private communications.

-32-

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-25. Strength Distribution of Isoscalar Vibrations
around Thermal Equilibrium
S. Yamaji, H. Hofmann, * and A. S. Jensen**[Large scale collective motion, giant resonance, linear response theory.]
Thermal properties of finite nuclei havebecome of great interest. Usually theoreticalstudies concentrate on thermodynamical
features in the proper sense, such as the free ·energy, entropy or nuclear density. These
quantities characterize static states. We wish to
focus on dynamical proreties, such as positions
and widths of specific excitations and theirrelative strengths, and study their temperaturedependence.
The aim of the present study!) is threefold.
Firstly, computation of the strength has its own
merits. We believe that the case chosen is
typical of isoscalar modes in general. Secondly,
we hope to contribute to the understanding of
the transition from microscopic to macroscopic
dynamics. Indeed, for the static energy one
knows how the disappearance of shell effects
turns the energy functional into one given by
the liquid drop model. The variation of strength
distribution with frequency provides
information about quantities representing
dynamical features, like e.g. the vibrational
inertia. Thirdly, such a study may help tounderstand recent fission experiments, whichindicate that motion is storongly overdamped atfmite excitations.
We study collective response as functions of
excitation for a typical isoscalar mode. We
apply a quasi-static picture in which theeffective coupling constant changes withtemperature T.

The dissipative part of collective response
function for the quadrupole mode has been
evaluated for 208 Pb. The important features ofour results are summarized as:a) For a comparatively small value of T = 0.5
MeV we observe the usual structure withpronounced resonances at low and higher
frequencies.
b) With increasing T this structure is wiped
out. This is expected since the widths of the
intrinsic single particle states effectively become
broader.
c) More exciting is the clear evidence of ashift of strength from high frequencies to lower
ones. This effect is mainly due to the Tdependence of the effective coupling constant.
d) At larger T there is a clear concentration ofstrength in one prominent mode at very low
frequency. The associated inertia is the one ofirrotational flow.
e) The transition from low to high Tbehaviour seems to occur at temperatures of
1.5 - 2 MeV.
f) The degree of damping increases steadily
up to temperatures of 3 - 4 Me V. The motion isstrongly overdamped at high T.
References
1) H. Hofmann, S. Yamaji, and A.S. Jensen :Phys. Lett., B286, 1(1992).

* Physikdepartment der Technischen Universitat
Miichen.

** lost. Phys. Astronomy, Univ. Aarhus.
-33-

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-26. Quantal vs. Semi-Classical Treatmentof Nucleon-Nucleon Collisions
M. Tohyama[Heavy-ion reaction theories, numerical silnulation.]
The numerical solution of the VlasovUehling- Uhlenbeck (VUU) equation is compared with that of the time-dependent
density-matrix theory (TDDM).l) It is
known that VUU is a semi-classical limit of
TDDM. We consider a collision of two identical 2-dimensional slabs which are finite in
one direction (the z direction) and infinite in
the other direction (the x direction). The
thickness of the slab is about 2fm and theincident energy is Ecm/ A=10MeV /nucleon.
We show in Fig.l the time evolution of Qzx
defined by Qzx =< p; > - < p; > where< A > denotes a mean value of a variable A.
The quantity Qzx is a measure of the deviation from equilibrium in momentum space.
The curves denoted as Vlasov and TD HF
are the results of classical and quantal calculations without nucleon-nucleon (NN) collisions. Each peak of Qzx in Fig.l corresponds
to the maximum compression of the colliding
slabs and the decrease in Qzx towards the final stage corresponds to the expansion of thesystem. The Vlasov result shows a temporal behavior which is similar to the TDHF
one. The maxima of Qzx calculated in VUU
and TDDM are reduced as compared withthe mean-field values. This is an expected effect of NN collisions: the momentum transferfrom the z direction to the x direction causedby NN collisions reduces the anisotropy inmomentum space, resulting in small valuesof Qzx' To compare the relaxation speed between VUU and TDDM, we show in Fig.2 theratio of Qzx with to that without NN collisions for the initial stage of the time evolution. There is a significant difference between
TDDM and VUU: the initial relaxation of
the anisotropy in momentum space is slower
in TD D M than in VUU. This may be attributed to a difference in the collision term:
the VUU collision term treats NN collisions
as Markoff processes while the TDDM one
does not.

0.8 ~---------.
~

0.6,........

- ,... ...

~,...... -.,.,.............'. ' "~-.~... '.'.

~e 0.4-';"'\:.' , ,....

.......
~

cJ 0.2'........

0.0-0.2 -+--r----.---r-__-~o

2 4 6 8Time [10·23 s ]10Fig. 1. Time evolution of Qzx for a collision of twodimensional slabs at Ecm/ A= lOMe V /nucleon.
Solid, clotted, dashed and dot-dashed curves denote the results in TDDl\f, TDHF, Vlasov and
VUU, respectively.

1.2.....,.-----------.

.-

o 0.8

~

~ 0.4

o. 0

-+--~-__'T"-__- - - - I

o

2
4
6
Time [10·23 s ]8Fig. 2. Rat.io of Qzx with to that wit.hout NN collisions. Solid curve denotes the quantal calculationand dotted curve the semi-classical one.

References
1) IV!. Tohyama:PhY8.Rev.,C36,187(1987).

-34-

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-27. Structure of Neutron Rich Nuclei
A Typical Example of the Nucleus 11 Li
K. Ikeda
Neutron halo, exotic nuclei, radioactive nuclear beams, soft giant resonances, ][ resonance states, mean field correlations, pairing correlations.
Recent development in the experimental technique of using radioactive nuclear beams hasbrought a new stage of nuclear spectroscopy of
nuclei far from stability.l) An example of themost interesting results is the fact that the pshell nuclei near the neutron drip line, e.g., 11 Li,
14Be and 17B, have extremely large root meansquare radii.
The nucleus 11 Li among others has been studied most extensively as a typical example ofthe neutron drip line nuclei. The characteristic
properties of the ground state of 11 Li obtainedby the experiment are the following: (i) The
two-neutron separation energy is only 210 ± 80
ke V. We note that the first open channel of 11 Li
is the three-body channel of 9Li+n+n since thetwo-body systems of 9Li+n and n+n have nobound states. (ii) The matter root mean squareradius of 11 Li is determind to be 3.14 ± 0.06 fm,
much larger than 2.1 fIn obtained from the empirical formula of the stable nuclei, J375roA 1/3. (iii) The transverse momentum distributionof 9Li obtained from the inclusive reaction,
11 Li+C-+ 9Li+anything, has the narrow Gaussian component in addition to the normal wide
component. 2 ) All these properties of 11 Li seemto support the so-called neutron halo in which
the two valence neutrons move in a wide spatial
region.
When the neutron-halo structure is realized innuclei far from stability we expect new kinds ofcollective motion such that outer neutrons in thehalo move against the remaing core nucleus. 3 ,4)The frequencies of these kinds of collective modeare expected to be low and their amplitudes
to be large, compared with the corresponding
collective motions in stable nuclei( or core nuclei). Therefore, we call them soft collectivemodes. 3 ) A typical example is the soft giant
dipole-mode. Experimental identification of thismode has been attempted through the studies of
the Coulomb excitation of the high energy projectiles of 11 Li and others. 5 ,6) If this kind of soft
dipole mode will be found, the halo-structure of
the ground state is considered to be supported
furthermore.
The first problem which should be examinedtheoretically is whether or not we can reprod uce the peculiar structure in which two valence
nuetrons are coupled weakly with core nucleus
and are correlated with each other in the interaction fields of core nucleus. Here I would like toreport the theoretical studies on the structure of
11 Li in the framework of the microscopic hybrid
model which combines two dfferent kinds of themodel space, that is, the shell model space andthe cluster model space. The second problem iswhat kinds of new excitation mode, like as thesoft El mode, arise due to the special characteristics of the ground state structure. Based on
the microscopic studies these subjects are discussed in the report of Ref. 7.
References
1) I. Tanihata et al.: Phys. Lett., 160B, 380 (1985);
Phys. Rev.Lett., 55, 2676 (1985); Phys. Lett.,
206B , 592 (1988); 1. Tanihata: Nucl. Phys., A478,
795c (1988); ibid. A488, 113c (1988).
2) T. Kobayashi et al.: Phys. Rev. Lett., 60, 2599
(1988).
3) K. Ikeda: INS Report JHP-7(1988)[in Japanese}.
4) P. G. Hansen and B. Jonson: Europhys. Lett., 4,409 (1987).
5) T. Kobayashi et al.: Phys. Lett., B232, 51(1989).
6) T. Kobayashi: Nucl. Phys., A538, 343 (1992).
7) K. Ikeda: Nucl. Phys., A538, 355 (1992).

-35-

RIKEN Accel. Prog. Rep. 26 (1992)

III -1- 28. Analysis of 9Li + n Resonances in lOLi by
the Complex Scaling Method
Interaction between 9Li and Neutron
K. Ikeda and K. Kato
[Unstable nuclei, resonance, complex scaled OCM, neutron halo.]
Knowledge about the 9Li-n interaction is very
important to understand the exotic structure of
11 Li which is a typical example of neutron-richnuclei. The experimental information about thestructure of low energy resonances in the lOLi
system has been obtained recently by Bohlen
et al .. 1 ) The theoretical subjects are to determine quantitatively the 9Li-n interaction basedon those experimental results and develop understanding of the structure of 9Li+2n. 2)
We have studied the resonance structure of
the 9Li+n system by using the complex scaled
OeM within the single channel approximationand determined the reliable 9Li-n interaction
which consists of the central potential and l·s
potential. The complex scaled oeM is shownto give us the resonance energies and the resonance widths precisely. By choosing the 11 Be
system, we have determined the l·s potential bysolving the neutron motion around a lOBe-coreso as to fit the observed data.
We have calculated resonance states of the
9Li+n system by using the folding central potential and the .e·s potential. To fit the resonance energy (0.42 MeV) of the observed ground1+ state, we found optical 8-values in the 9Li-nfolding central potential. The resonance statesobtained by the 9Li-n interaction are summarized in Fig.I. The calculated resonance widthsof (Pl/2' 1+) and (P3/2' 2+) have been shown to
be in the same order of magnitude but larger
than experimental ones. The shortcomings ofthe present model are that i) the calculated resonance widths are large and that ii) the second
excited resonance state is calculated at a toohigh energy in comparison with observed data.
The shortcomings mentioned above suggest
the activation in degrees of freedom of the 9Licore. We are undertaking a comprehensive

study on the resonance properties of lOLi in
the framework of the channel coupled complex
scaled OeM, in which the 9Li-core excitations
are taken into account. Furthermore this study
should lead to a study on the 11 Li structure
which includes the effects of the 9Li-core excitations.

-7~_Ir.,8-18MeV I•

II I ~ I I I I I II/';

4.47W;P~

U(/:.!t/:i;{:7$ r=O.30MeV. +0.80IlI77/11I7/ 2
0.42 ~;iTrf'T"r"r-r-rt"rY
E(Mev)---'------

9 U +nI"EO.ISMaV+

0.42 'nil I If II I I I ) 1
E(MeV)

Cal.

Exp.

Fig.l. Calculated and obserbed resonance states of lOLL
(MHN potential case)

References
1) H. G. Bohren et al.: preprint.
2) Ie Ikeda: Nucl. Phys., A538, 355(1992).

-36-

RIKEN Accel. Prog . Rep . 26 (1992)

111-1-29. Two-Neutron Removal Cross Sections of llLi
K. Soutome, S. Yamaji, and M. Sano
[Unstable nucleus, neutron halo, nuclear reaction, Glauber model.]In the past few years there have been many studies ofnuclei far from stability, especially of the extremely
neutron-rich nucleus 11 Li. The nucleus 11 Li is known
to have a neutron "halo", which is made of twooutennost neutrons bound weakly around a 9Li core.
From this halo. structure of llLi, it was suggested that
there could exist a new type of collective excitation, soft
giant dipole resonance, and this resonance will be foundby experiments of Coulomb dissociation. Suchexperiments were perfonned by Kobayashi et al.; 1) theymeasured cross sections for the two-neutron removal
process 11 Li + Target ~ 9Li + X at E lab = 0.8 Ge V/
nucleon. In order to- discuss the Coulomb dissociationof 11 Li, however, one must subtract nuclear
dissociation cross sections from measured crosssections. To estimate nuclear contributions, Kobayashi
et al. adopted a naive geometrical model, the so-called"factorization model",2)This naive geometrical approach has been, however,criticized by several authors. For example, the"diffractive eikonal model" of Bertsch et al. 3 ) yields
steeper target mass number dependence of the nuclear
dissociation cross section than the factorization model.
They claim that the factorized fonn of the cross section
does not apply to the "halo" nucleus 11 Li.

In contrast with such calculations, our recent
Glauber calculation4 ) indicates that the factorization
model works well for the nuclear dissociation of 11 Li.
In Fig. 1 we show calculated nuclear dissociation crosssections together with those deduced by Kobayashi et al.
The solid curve was calculated by using the two-neutron
density distribution of the following Yukawa form:p(q, r2) = PYK(f}) PYK(r2), PYK(r) = N{l-exp[-(r/b)4]}
xexp[ -ar]/r2, where we have chosen the values of a and b
as a = 0.4 fm-1 and b = 2.43 fm. In order to see the"halo" structure of this model density, we show in Fig.
2 the density distribution of 11 Li. The shaded area
represents the bounds within which interaction crosssections can be calculated consistently withexperimental data. 5)
From Fig. 1 we can conclude that the factorization
assumption indeed holds for the two-neutron removal
process of 11 Li.

600.--------------------------------------------------------------.
Nuclear Dissociation of 11 Li

1~~----~----~----L-----~--~

fOl;S 10.

2

~

....:
fofl

= 10.
Q

3

Q.I

:c

10. 4

! 400
=
.g

Cj

Q.I

o

rJ)
fofl

~

2

4

6

8

10

r [fm]

200

U"'"

Fig. 2. Density distribution of 11 Li.
• Factorization Modelo~----~----~------~----~~

o

100

200

Target Mass Number
Fig. 1. Nuclear dissociation cross sections for the twoneutron removal process of 11 Li.

-37-

References
1) T. Kobayashi el al.: Phys. LeU., 8232, 51 (1989).
2) D. L. Olson el al.: Phys. Rev., C28, 1602 (1983).
3) G. Bertsch, H. Esbensen, and A. Sustich: Phys. Rev.
C42, 758 (1990).
4) K. Soutome, S. Yamaji, and M. Sano: Nucl. Phys.,AS38, 383c (1992); Prog. Theor. Phys., 87, 599(1992).
5) I. Tanihata el al.: RIKEN-AF-NP-119 (1992).

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-30. Higher Order Electromagnetic Interaction in the
8B Breakup Process
N.Iwasa[208Pb ( 8B , 7Be p ) 208Pb; Coulomb breakup, higher order effect.]Capture reactions at stellar temperatures canbe studied by the Coulomb breakup method.
If the breakup is via the one-step Coulomb
excitation mechanism, direct correspondence
between the cross sections of capture andbreakup reactions is expected.
This
correspondence may be deteriorated by higher
order electromagnetic interaction. G. Baur etal. developed a method to evaluate the higher
order effect based on the sudden
approximation. 1) They found considerable
distortion in the angular distribution of the
breakup fragments in their rest frame for thecase of 11 Li + 208Pb ---+ 9Li + 2n + 208Pb at 30
MeV/u. In this paper the higher order effect isestimated for the El breakup process
8B+208Pb---+ 7Be+p+208Pb at 47 A Me V2) and
300 A MeV by the method of Baur et al.
Figures 1 and 2 show calculated angular
distributions of the fragments in the plane

c
0
'a
u
0,)

CZl
til
til

0

~

U

0,)

>
'a
(Ij

0

cG

1.4

~b('B.7Be p)208Pb

47 A MeV

1.2
1.0
O.S
0.6
0.4
0.2
0.0

-100

o

100

c
o

1.4

1.2
~ 1.0

'a
(,)

v.l
v.l

8

0.8

U
o

0.6

>
'a
(Ij
a:3
cG
-100

o

100

$
Fig. 2. The same as Fig. 1, but for the incident energy Ein= 300 A MeV.
perpendicular to the beam axis. The relative
energy between 7Be and proton is fixed to 300
ke V. The impact parameter is set to be 15 fm,
which corresponds to the scattering angles of
6° and 1° for the incident energies of 47 A MeV
and 300 A MeV, respectively. Dotted curves
represent the cross sections calculated by the
fIrst order electromagnetic interaction only, andsolid curves are for the full calculation
including all order.
The higher orderelectromagnetic interaction is less important
than in the 11 Li breakup, 1) though it is still not
negligible. As shown in Fig. 2 the higher
order effect diminishes at 300 A Me V.
Therefore it is of interest to compare theexperimental results at low and high incident
energies.

$
Fig. 1. Azimuthal angular distributions for the 208pb(SB, 7Be p) 208pb reaction at Ein = 47 A MeV. Dottedand solid curves represent the first and all order
calculations, respectively.

References
1) G. Baur, C. A. Bertulani, and D. M. Kalassa: preprint.
2) T. Motobayashi et al.: This report, p.19.

-38-

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-31. Possible Existence of a Bound State in iLi
K. Ikeda and T.Yamada·[:E-hypernuleus, :EN interaction, supermultiplet.]
The possible existence of bound JLi states l ) wasinvestigated within the frame of the microscopic a+"2N" +E cluster model by employing the effective
E-N interaction which reproduces the experimental
binding energy and width of riHe. 2 ) We found aplausible JLi bound state with binding energy of
EO BEo =1.2 MeV and width r : : : 5.4 MeV (SeeFig. 1). The width comes only from the conversion process EN -+ AN because of the bound state.
The bound state shows the mixed charge states with
about 83% of total isospin 1=1, which consists of the[6Li(1i)®EO] and [6He(li)®E+] configration. This
is in contrast with the fact that the ~He bound stateis an almost pure isospin 1=1/2 state.

is much larger than the energy difference (about 1
MeV) between the [6Li(1i)®EO] and [6He(li)®E+]
states. Therefore, the two states are coupled strongly
to produce the bound state. On the other hand, thestrength of the Lane potential is relatively smaller
than the energy differences among [6Li®E°], [6He®
E+] and [6Be®E-] states with the nuclear-core isospin t= 1. Therefore, the three states are not coupledstrongly. [6He®E+] configrations appear mainly due
to the (fry . ~)( SN • SE ) terms of E- N interaction. (SeeFig. 2).
v
'0

7L~ I

6

1

6He

6Li

2'

"

4

10

~"

//

6Be

6Li+~·/f----..L.

;,- -"1------o=-.. .~./~2'2' ......

_3_'

o

2

(b)
L- if

MeV

2

(a)

-,-'

/--j

6He+~ / ;'~!oFig. 2. (a) Isobar-diagram of the A=6 body nuclear
system and (b) various Eparticle decay thresholds for
E7Li.

~

MeV

Fig. 1. Dependence of the Fermi momentum kF on thebinding enegies of i Li and E4 He.
The reason why such a bound state appears in
JLi is summarized as follows: The coupling potential between the [6Li(li)®EO] and [6He(1i)®E+]
states comes only from the (~ . ~)( SN • SE )term of
E- N interaction since the (~ . ~ )( SN • SE) term plays
a role of coupling between the state with nulear-corespin s=l and isospin t=o (6Li(li)) and the statewith s=O and t=1 (6He(li)). The coupling strength

In conclusion, we have shown the possible existence of the bound JLi state. IT this E-hypernucleus
is observed, we can get the direct information on(~ . G)(SN . sE)term of E-N interaction from thebinding energy of JLi. Therefore, it is highly desired that hypernuclear production experiments
such as a 7Li(K- ,1('- )JLi reaction will be performed
to study the possible existense of the bound JLi hypernucleus.

References
1) T.Yamada and K. Ikeda: Phys. Rev., C46, 1315 (1992).
2) T. Yamada and K. Ikeda: Prog. Theor. Phys., 88, 139(1992).

·Dept. Appl. Sci., Kochi Women's Univ.

-39-

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-32. ~He Hypernuclear States and Roles of the Spin-Iso spin Termof I-N Interaction
K. Ikeda and T.Yamada*[Hypernuclei, ~-N interaction, isomutiplet.]An evidence of the r;4He bound state was observedin the 4He(stopped K-, 1£'-) experiment at KEK.l)
It is an interesting subject to investigate whether
bound states and/or quasi bound states could exist
in other light ~ hypernuclei with use of the effective~-N interaction which reproduces the experimental
binding energy and width of ~He. For this purpose, we have to clarify the characteristic propertyof the strong spin-isospin dependent ~-N interaction
which has a role to make couple the different charge
states. 2 ) The [3H+~+] + [3He+~O] model is applied
to a study of the structure of r;4He to make clear theroles of the spin-isospin terms of ~-N interaction.
The eigenvalue and eigenfunction of ~ He are obtained by solving the coupled channel equation. The
kF-dependence of the density dependent effective interaction obtained from the Nijmegen model D potential3) is shown in Fig.! (solid line) for the calculated binding energy Br;+ and width r. When thevalue of kF is chosen to be 0.86 fm -1, we found one
bound state with Br;+
3.2 MeV and r
7.8 Mev
and could reproduce the experimental data. The
obtained bound state shows an ahnost pure isospin
eigenstate (I~I/2) . The reason why such an almost
good isospin state appears in spite of the large energy difference ("" 2.6 MeV) between the 3H+~+ and3He+E o thresholds is given as follows: As shown in
Fig. 2, the 3H+E+ potentail has a repulsive part in
the inner region. Therefore, there appears no bound

=

MeV

4

~
................................

o
4

8

0.8

B~·

....... .. ........

~

2

=

0.9

------=;

MeV

Fig. 1. kF dependence of the calculated binding energy
Blj+ and width r .

R(fm)

4

Fig. 2. Potentials for the 3H+~+ (Vll :thick solid curve)and 3He+~o (Vn:thick dashed curve) channels. The
fine solid curve denotes the coupling potential V 12 .

state in the case of the 3He+Eo channel. On theother hand, the coupling potential between the twochannels, VIf o, has a large magnitude. Its value
amounts to about 10 MeV. It is much larger thanthe energy difference ("" 2.6 Me V) between the two
thresholds. Therefore, the two basic charge states
are coupled strongly.
As shown in Fig. 2, the origin of the large repulsive character of VIf o consists of the two constructive contributions; about ~ and ~ of the total
amount come from the LNvEN(SN' sr;)and LNvN'(~ . tr;)( SN . sr; )parts of the E- N interactions, respectively. Thus, the LNvN (~. tr;)(SN' sr;)part of the~-N interaction plays an important role to form the~He bound state .

References
1) R. S. Hayano, et al.: Phys. Lett., B231, 355,
(1989).
2) T. Yamada and K. Ikeda: Prog. Theor. Phys.,
88, 139 (1992).
3) M. M. Nagel, T. A. Rijken, and J. J. de Swart:
Phys. Rev., D12, 744 (1975) j ibid.,D15, 2547
(1977) ; ibid., D20, 1633 (1979).

·Dept. Appl. Sci., Kochi Women's Univ.

-40-

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-33. Highly Excited States of !Li by the Microscopic Cluster Model
K. Ikeda, H. Ohkura: and T Motoba-[ Hypernuclei, hole state, cluster model, (1<- 11"-) reaction. ]In order to explain the high-lying sharp peak observed at 18.3 Me V excitation in the 6Li(l<- , 11"-)~ Lireaction, I> which cannot be described with the
a+p+A configuration,2> we have applied the m.icroscopic 3He+d+A cluster model for the first time.
This model has the broken-a degree of freedom. 3)
We employ the NN interaction which describes highlying states of 5Li with the 3He+d cluster model andsuch AN interaction as to reproduce the experimental A-binding energies of ~He(Ots. and 1+ states).
In the three-body cluster calculation, as shownin Fig. 1 , it is notable first that two J = 1+
eigenstates (L0, S1) are obtained below the
3He+d+A threshold with their inter-cluster binding
energies being 3.18 MeV and 2.10 MeV, respectively.
Specifically the lowest state( 1t , SN
3/2 dominan t)
is calculated to be below the ~ He+d and 3He+~ H

=

=

=

a+p+A

3He + d + A
6Li (K',rr'),,6u

1.5

PK=790McV/c
I

'"'

<I)

::0

+

e =0°
71'

1.0

E
0.5

g.s.

t

1,1

\1
I I

0.0
0

10

Ex

15

P20 2'

30

thresholds as a non-trivial consequence of the threebody dynamics, while the second state{lj, SN = 1/2
dominant) is just above the ~He+d threshold. All
the other eigenstates appear separately, more than 2
MeV above the 3He+d+A threshold - more than 4
MeV above thestate.
Secondly both 1+ states are very strongly excitedin the forward (K-, 11"-) reaction on the target 6Li =a+d (iN0, S1; J1+) through the recoilless~L
0 transition. We calculate a cross section forthe (K-, 11'-) reaction by the distorted wave impulse
approximation(DWIA).Thus we found that the third
peak consists of these two 1+ states. If we employ
the emprical elementary cross section 4.0 mb/sr, thethird peak cross section is predicted to be d~~) (0°) =0.87(li)+0.63(1t) 1.50 mb/sr, which is 1.7"", 2.3
times as large as the shell model estimate.

It

=

=

=

=

=

Thirdly, mak.ing use of the a+p+A model andestimate for the second peak d~~) = 1.61 mb/sf,
the experimental ratio between the second and thirdd (3) d (])
peak strengths ( ~o / dO ) 0.85 0.99 can be reproduced satisfactorily (0.91) by the present clustermodel. For such high-lying states it seems hard to
explain the ratio with the shell model.
The 3He+d+A microscopic cluster model works
well for the understanding of the structure of highly
excited states in view of all the consistency between
the experimentally observed properties and the calculated results on the energy position, narrow width,
and the reaction cross section of the third peak.

=

f',j

3He + A 3H(MeV)

4
A He+dFig. 1. Experimental 1) and theoretical excitation
functions for the (K-, 11'-) reaction at PI(
790
MeV and 8=00with the decay channel thresholds
indicated. A smooth curve shows the exci tation
function consisting of two Gaussian peaks{second
and third peaks) and a Lorentzian bump for theexperimental background.

=

References
1) R. Bertini et aI. (Heidelberg - Sac1ay- Strabourg Collaboration): Nucl. Phys"
A368, 365 (1981); A360, 315(1981).
2) T. Motoba, H, Bando, and K. Ikeda: Prog.
Theor. PhY8., 70, 189{1983}; 71, 222 (1984).
3) T. Yamada, K. Ikeda, H. Bando, andT. Motoba: PhY8, Rev., C22, 2073 (1980).

-Graduate School of Sci. and Technol.,Niigata Univ.
-·Lab. of Phys., Osaka Electro-Communi. Univ.

-41-

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-34. Light I Hypernuclei I - Atoms
K. Ikeda and T. Yamada*[:&:hypernucleus, L atom, EN interaction, isomultiplet, supermultiplet ]This report is a review work on the structure of(!

He, ~ Li and ~ Be ) andlight 1: hypernuclei
analyzed 1: atoms. We dedicate this article for the
memory of prominant activities of late Prof. Jan
Zofka (Nuclear Physics Institute of Czechoslovakia,
Rez, Prage).l) The summary of this article is given

hypernucleus isobserved, we can get the direct

information on the (tN' tI) (CJN' OI) terms of IN interaction from the observed binding energy of~ Li . Therefore, it is highly desired that thehypernuc1ear production experiment such as a
7Li(K-, 1C) ~ Li reaction will be performed to~ Li

as follows:

study the possible existence of the bound(1) The structure analysis of ~ He was performed
within the frame of the [3H+ 1:+] + [3H+VJ] model.
2) The bound state of He obtained shows analmost pure isospin eigenstate ]=1/2. This is due tothe fact that the coupling potential between the
3H+ 1:+ and 3H+1: 0 channels (namely, Lane

hypernucleus.
(3) For the ~ Be hypernucleus, we have applied
the coupled-isomultiplet model 4) which takes into!

potential) has large magnitude and its strengh ismuch larger than the sum of the mass difference
and Coulomb energy difference between the twochannels. It should be noted that the strong Lane
potential in the case of
He consists of two!

contributions from the (tN' tI) and (tN ' tI) (<TN.
0I) terms of I-N interaction because of thenuclear core with isospin 1/2 and spin 1/2, and thelatter contribution is about twice larger than theformer one.
7(2) The possible existence of bound ~ Listateswas inverstigated within the frame of the
microscopic
a+ "2N" + I
cluster model by
employing the effective I-N interaction
which
reprod uces the experimental binding energy andwidth of ~ He. 3)
We found the plausible ~ Libound state with B=1.2 MeV and r = 5.4 MeV. The
width comes only from the conversion process IN-+ AN because of the bound state. The boundstate shows the mixed charge states with abount
83% of total isospin 1=1, which consists of the[6Li(1 +)and [6He(0+) 11] configurations. This isr>]

in contrast with the fact that the ~ He bound stateis an almost pure isospin 1=1/2 state. The different
binding mechanism between the ~ Li and : He
hypernuclei comes from the different nuclear-corespin and isospin of the respective I-hypernuclei«s,t) = (0,1) , (1,0) for 6He- 6Lr 6Be and (s,t) =(1/2,1/2)
It

for

3H-3He). If the

bound

~Li

Dept. of Applied Sei., Kochi Woman's Univ.

-42-

account the isospin coupling between the A=8
isotriplet (SLi,SBe,SB) and I particles (11,
l:).

r> ,

The EI =10 Mev peak observed in the 9Be (K-,1C)~ Be reaction was interpreted as an almost pureisospin 0 state if we use the same coupling strenghof the Lane potential as that estimated by Dover eta1., who analyzed the spectra of 12c(K-,1C) ~Be, ~Creactions. The microscopic calculation for ~ Be isin progress 4) with use of the effctive 1:- N
interaction which repreduces the experimental
binding energy and width of !He.
(4) The combined analysis of 1: atoms and~ He was performed with u~ of the Nijmegen OBE
potentials and was found to be useful to know thecharacteristic differences among them, since we
can investigate the inside ·and outside behaviors of
the I-nucleus potential on equal footing. 5) The
model D (F and NSC (soft core»can (cannot)

reproduce both the binding energy and width of~ He. On the other hand, it is concluded that thesystematic reproduction of the atomic data cannot
be obtained with the existing OBE potentials in theframework of the present treatment.
References
1) T. Yamada and K. Ikeda : Czechoslovak J. Phys.
(1992). to be published.
2) T. Yamada and K. Ikeda : Prog. Theor. Phys.. 88,
139 (1992).
3) T. Yamada and K. Ikeda : Phys. Rev., C48 (1992), tobe published.
4) K. Ikeda and T. Yamada: Int 1. Mod. Phys .• A3,
2339 (1988) ; O. Richter, M. Sotona, T. Yamada, K.
Ikeda, T. Motoba, and K. Itonaga : Few Body
Systems, Suppl. 5, 379 (1992).
5) T. Yamada : Few Body Systems, Supp1., 5, 334(1992).

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-35. Production of Double A Hypernuclei from a Formed 8
Hypernuclear State
K. Ikeda, M. Takahashi,· and Y. Yamamoto**[Hyper nuclei, hole state, (K- ,K+) reaction, decay width.]
Recently a new experiment of the (K-, K+) reaction has been performed with use of a scintillating fiber target (KEK E-224). Because of thelarge momentum transfer of the elementary process
K-N~K+3-, the dominant part of K+spectrum
is of a quasi-free production of :=:- in the highenergy side. The production cross section of bound3-states in the terget nucleus (12C) is considerd to
be quite small. There is a possibility, however, to observe AA states specifically produced after :=:-p-+AA
conversion in the .nucleus, even if the number ofbound-:=:- events is not large (estimeted as about 100
events). Here we evaluate the trasition probabilities
to three types of final AA states: two-A bound, oneA bound and one-A continuum and two-A continuum. Experimentally it may be possible to distinguish these three patterns of transition.
A 3-particle in a nuclear bound state reacts with
one of nucleons and then two A particles are produced. Now we define the partial conversion widths
rbb,r be and ree where suffixes b, c mean boundand continumm states, respectively. Then the corresponding probabilities are given by Pbb = rbb/r,
Pbe = rbe/r and Pee = ree/r with r = rbb + rbe +r ee' In the second-order perturbation we have[£][S}[T]- L "AIlAI
L "AllAl
L L [f~][s~][t~]

rbb _

",l,

LST

-

-

distribution of hole-excited states. It should be notedthat rbb gives the strength of the energy-conserving
transition to two-A bound and hole-excited states. IIr ",l. = 0, the last parts in above expressions reduce
to a delta function.
Here we calculate the partial conversion widths
given in Eqs.(1)-(3) in the cases of 3-absorption
from nuclear orbits in 11 B core. The 3N-AA coupling interaction V:::N,AA is dominated by the T=O
I So component and taken as three range Gaussian
form. The :=:- in a nuclear orbit is considered to react with a deep Is proton, whose width r l l is taken
as 10 MeV.
For convenience we represent all needed wave functions, 3- -nuclear,A-bound,A-continuum and protonbound ones, on the Gaussian bases. We have calculated :=: and A hypernuclear states of the 11 B + 3and lOBe + A systems with the folding central potentials from 2-N and A-N gaussian interactions.
The A continuum wave funciton is normalized as
J2/1r sin(kr-1r/2 +6d asymptotically, and expanded
in terms of Gaussian functions.
Table 1. Calculated partial conversion widths and corresponding probabirities. B:;: is the binding energyof =: particle.

B:::(MeV)-x < a:::l:::nhlhIV:::N,AA InAI fAI nAlf Al >'iST
rn.fh
(l)

5.1
9.9

t

XJ

[£][S][T]

L L 10 dk LST~ [l:::][s:::][t:::]",l, "AIlAI lAl

rbe = L
X

'"

Al

15.7

< a:::i:::nhihIV:::N,AAlnA1lAI kA,lAl >LSTr ",i.
(2)r ee = similar formula,(3)

where la:::l::: >, Inhlh >, InAfA > and IkAlA > denote a 3-nuclear state, a proton-hole state, a Abound state and a A-continuum state, respectively,and €:::, f",l, and €"AlA are corresponding singlepaticle energies. A width of hole states r ".l" which
has a large value for a ground 1s-state, is related to*Niigata U~iv.)**Tsuru Univ.

ree

rbb
(Pbb )

rbe(Pbe )

(Pee)

0.199
(0.118)0.362(0.211)
0.978(0.502)1.453(0.863)1.323(0.771)
0.941(0.483)0.032(0.019)0.030(0.017)0.028(0.014)In Table 1, we give preliminary calculated values of r bb , rbe and rcc (Pbb , Pbe and Pee). Here
B:::=5.1, 9.9 and 15. 7(Me V) correspond to the potential strength(V o) for -20, -30 and -40(MeV) with therange of 1.034(fm), respectively. The force strengthand range for A are fixed to be -42.01MeV and1.034fm. It is shown that 2A continuum probability is very small in comparison with others and that
two A bound probability increases with increase of
B::: while one-A bound and one-A continuum one decreases with it.

References
1) M. Takahashi, Y. Yamamoto, and K. Ikeda:
Physical Society's Autum Meeting, 1, 51(1992).

-43-

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-36. URASiMA: An Event Simulator for URHIC
S. Date and H. Sumiyoshi[High energy reaction, multiparticle production, event simulator.]
Acti vities in the field of ultrarelativistic
heavy ion collisions (URHIC) are predomi'natedby the aim of finding a new state of stronglyinteracting particles, the Quark-Gluon Plasma(QGP). To obtain a clear trace of the QGP
formation, it is necessary to distinguish QGP
signals from effects of hadronic final stateinteractions in nucleus-nucleus (AA) collisions.
With this purpose, we have developed a newMonte Carlo event simulator URASiMA (UltraRelativistic A A collision Simulator based on
Multiple Scattering Algorithm).
Among existing event simulators such as
VENUS, MCFM, Fritiof and RQMD, URASiMA
aims at being the most reliable one. URASiMA
employs a conventional hadronic level
multichain model 1) with known hadron-hadron(hh) and hadron-nucleus (hA) data as the input
instead of introducing quark-string models as thequoted simulators do.
URASiMA code is an extension of two existingcascade codes called MCMAA and MCMHA,
which have been designed to analyze cosmic ray
da ta. 2) In contrast to the previous two codes,
URASiMA deals wi th pp to AA collisions
systematically. It regards motions and (pointlike) interactions of particles in the full 3+1
dimensional space-time. The code satisfies fullcovariance under the Lorentz transformations andthe full energy-momentum conservation.
The present version of URASiMA includes
elastic and inelastic NN, rc N and ~ Ninteractions. Productions of K 's, anti nucleons and~ resonances are considered in inelastic collisions
besides with copious 1t productions.
We have already reported at somemeetings 3) that our simulator reproduces theglobal data in the central rapidity region of 200
GeV 16 0 + A reactions taken at CERN SPS. Our
preliminary calculation on the transverse energy
distribution in the target fragmenta tion region of
160 + 184W collisions at 200 GeV shows a good
agreement with the experimental data 4 ) when we
include internuclear interactions with theformation time 'to = 1.2 fm for pions.
We have made preliminary calculations to

examine the role of the pion absorption. To dothIs, we have introduced a phenomenologicalparameter Pabs which determines the rate of theabsorption among produced low energy pions. Our
result shows that, in the fragmentation region,
the calculation with Pabs = 0 (no absorption)overestimates pion yield, underestimates baryon
yield and overestimates proton's PT slope, incomparison with the experimental data. 4) Thesesystematic deviations have been decreased
significantly by introducing the pion absorption
processes with non-zero Pabs. We have not madea full parameter search for the value of Pabs and
we do not proceed this further in this report. We
have also made a preliminary calculation on theK+ /rc+ ratio, whose observed enhancement has
been regarded as a candidate of the signature of
QGP. As a result, we have obtained a strong
rapidity (y) dependence in the ratio; it increases
rapidly when y changes to the target
fragmenta tion region from the mid rapidity
region. This dependence agrees with ameasurement done by the E802 group at AGS.5) If
our understanding of the K+ /1t+ enhancement iscorrect, the ratio is expected to increase inproportion with nucleon densi ty squared, since
pions are mainly absorbed by two nucleon systems.
We believe that URASiMA provides animportant base to study and understandmechanisms of particle production in ultrarelativistic heavy ion collisions.
References
1) A. Capella, U. Sukhatme, C. I. Tan, and J. Tranh
Thanh Van: Phys. Lett. ,81B, 68 (1979); K. Kinoshita,
A. Minaka, and H. Sumiyoshi :Prog. Theor. Phys. ,61,
165(1979); ibid .•63, 928 (1980) ; S. Date, M. Gyulassy ,and H. Sumiyoshi: Phys. Rev., 032,619(1985).
2) M. Fuki: Ph.D. thesis, printed in The Bulletin of the
Okayama University of Science, 22A,167 (1987) ;Y. Iga et. al.: Z. Phys.,C38, 557(1988) .
3) S. Date and H. Sumiyoshi: Proc. Int. Symp. on HighEnergy Nucl. Colli. and Quark Gluon Plasma, June,
1991, Kyoto, Japan (1991).
4) T. Akesson et. al..:Z. Phys. ,C38, 383 (1988).
5) S. Nagamiya: talk given at the Quark Matter '91
Conf., Nov., 1991, Gatlinburg, U. S. A. (1991).

-44-

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-37. Multiplicity Dependence of the Chaoticity Parameterin HBT Measurements

J. A. Casado* and S. Date
[High energy reaction, multiparticle production, identical particle correlation.}

Chaoticity parameter in the normalized twoparticle correlation function for identicalparticles provides unique information on thequantum phase correlation between particle
emission sources in high energy particle reactions.
In spite of this fact, behaviors of the chaoticity
parameter are not studied closely up to now.
In this work, we have tried to understand a
recent measurement l ) on the multiplicity
dependence of the chaoticity parameter. To dothis we employ a semi-classical model ofmultiparticle production. 2)
In this model, pions are produced from a cnumber source J(x) via Klein-Gordon equation forthe second quantized pion field <p(x) . It is wellknown that the solution of the equation for theasymptotic final state is given by a coherent stateof pions. If we assume that the pion source iscomposed of classically identical N sources, we
can writeN

The expressions for the correlation functions 2)
provide the tandard formula of A for the BoseEinstein correlation when we assume randomly
distributed phases. In this case, A increases as afunction of <N>, average source number, which is
expected to be proportional to the charged
multiplicity. This tendency apparently conflicts
wi th the da ta shown in Fig. 1.
Assuming that the phases of the sources areconstants, we can reproduce the data as shown in
Fig.1. In this calculation, we have made further
assumptions that the Fourier transform of J(x) has
a flat shape in the rapidity space and that a
spread of p(x) is an order of 1 fm.
0 .5

0.'1

-

0 .3

-

o.~

-

ilP.

J(x) = Ie }r!.x-xy,
i=lwhere <Pi is the quantum phase and Xi is the spacetime position associated with the i-th source. We
assume that the positions (Xl, ... ,XN) aredistributed independent of each other according
to a distribution function p(x). Using the coherent
state, we can write down the n-pion correlation
function.
Given the correlation functions, the chaoticity
parameter A is expressed as
2(J A(Pikl») Jik(Pik,kl)

A=-J""-d-3k-<~P-/-(k---:"»- Jd3k/kipik,ki) -1(1)

Here PI (k) and P2 (kl ,k2) denote inclusive oneand two-particle densities, respectively, and< ... > stands for averages over the phases, thepositions and the number of sources, N.

0.1

0.0

L -'--'----4--,-1. __... __.---,--,--1_ •._.. J •.• -' .. _ .1 __....:·---L--J--,--,- _ _

o

5

L •.

10

Hi

20

dN/d71 (Charged)

Fig. 1. The chaoticity parameter as a function of
charged multiplicity. Data are taken from Ref. 1. A
solid curve shows our calculation for the maximum
coherent case.

Part of this work is supported by the program ofJapanese Government Research Awards for
Foreign Specialists promoted by the Science andTechnology Agency of Japan.
References
1) C. S. Lindsey: Nucl. Phys. , A 544, 343c (1992).
2) M. Gyulassy, S. K. Kauffmann, and L. W. Wilson:
Phys. Rev. ,C20, 2267 (1979).

* Departamento de Ffsica Teorica, Universidad de Santiago
de Compos tela.

- 45-

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-38. Pion Double Charge Exchange Reactions
Leading to Double Pionic Atoms
J. Nieves: E. Oset: S. Hirenzaki, H. Toki, and M. J. Vicente-Vacas·[Double charge exchange reactions, Double Pionic Atoms.]
Deeply hound pionic atoms in heavy nuclei are getting
increasing attention from both experimentalists andtheoreticians, since these states were found quasi-stable
and accessible experimentally with some suitable
methods. I) Deeply bound pionic atoms have aninteresting structure. The bulk part of the pion-nucleus
interaction is strongly repulsive and pushes out a pionfrom the nucleus to protect it from being absorbed,
while the Coulomb force attracts the pion to form abound state. Hence, the pion forms a pionic haloaround the nucleus. It indicates that all the observablesof deeply bound atoms are very sensitive to the pionnucleus interaction and the nuclear surface properties.
These features motivate us to think how a pionicsystem with many pions would look like. It would bevery interesting to make an object with more than two
pions in a single orbit. This will be the first case to
make a microscopic system with more than two hosons
in one quantum state. The double pionic atoms, inaddition, would provide a unique opportunity to study
the pion-pion interaction very precisely. A new field of
multi-hosons with multi-fermions interacting strongly
with each other will be open if we are able to createsuch states and study them experimentally. We mayfind pion condensation, which is however different fromthe zero energy regime discussed a lot in the past.
In this report, we would like to study theoretically aclear method to produce double pionic atoms. The idea
is the use of direct reactions, in which a particle isbombarded on a target nucleus and an outgoing particle
is measured. A sign for forming pionic atoms is a peakstructure in the excitation function just below the twopion production threshold. As the first trial, we look
into (1C ,1t+) reactions leading to double pionic atoms in
208Pb. 2) This is 1t-+208Pb~ 1t+ +(208Pb 1tb- 1tb-)with 1tb- a hound pion. We use the 41t interaction of
Weinberg3 ) to calculate the T matrix. We take pionic
atom wave functions by solving the Klein-Gordon eq.
with the optical potential of Seki and Masutani. 4 )Concerning the distortion, we take the eikonal
approximation. The purpose of doing this investigation
is to see what is the size of the formation cross sections
and what considerations are needed in order to find bettermethods.
We show in Fig.l the calculated cross sections at zero
degree as a function of the node quantum number n for
S, P, and D states (/=0, 1, and 2). The cross sections
decrease rapidly with n for each I. As for the angularmomentum dependence, they increase first by goingfrom 1s to 2p and then decrease from 2p to 3d.

10-3 ______~--______~__

10-6~~----~~~~~~

o

2

3

4

n
Fig. 1 The differential cross sections at zero degree leading

to double pionic atom states.

The energy of incident 1t-

is 500 MeV.
The (1t- ,1t+) cross sections leading to double pionic
atoms in 208Pb are found quite small d2cr/dEdQ - 10-3
- 10-4 Jlb/sr/MeV . We have calculated the backgrounddouble differential cross sections in the region of interest
using the pion cascade model and found to be around 2
Jlb/sr/MeV. Hence, the (1t-,1t+) reactions seem not to besuited for double pionic atoms. The findings of thepresent work should be, however, of use in future
exploration of alternative methods to produce thesestates.
References
1) H. Toki and T. Yamazaki: Phys. Lett., B213, 129(1988).
2) J. Nieves, E. Oset, S. Hirenzaki, H. Toki, and MJ.
Vicente-Vacas: Int. J. Mod. Phys., in press.
3) S. Weinberg: Phys. Rev. Lett., 18, 188 (1967).
4) R. Seki and K. Masutani, Phys. Rev., C27, 2799
(1983).

* Department of Theoretical Physics, Univ. Valencia,
Spain.

-46-

RIKEN Accel. Prog . Rep. 26 (1992)

111-1-39. Formation of Deeply Bound Pionic Atomsby (d, 3He) Reactions
S. Hirenzaki, H. Toki, and T. Yamazaki*[(d,3He) reactions, deeply bound pionic atoms.]
Since the suggestion of Toki and Yamazaki for theformation of deeply bound pionic atoms such as Is and2p states in heavy nuclei by direct reactions, there havebeen a number of experimental attempts to find thesestates. These states have a pionic halo structure due to astrong repulsive pion-nucleus interaction, which saves apion from being absorbed by the nucleus. We pushed
the use of the (d,3He) reactions that use a deuteronbeam. I) This process has an advantage to be able tochoose the incident deuteron energy so as to make thereaction recoilless. In this kinematics, the pion does
not have to carry any momentum into the target nuclear
system. Although (d,3He) reactions are not coherent
and hence lead to complicated nuclear configurations
together with the formation of pionic states, therecoilless condition may make the processexperimentally feasible. In fact, we showed that thecross sections leading to pionic atoms together withneutron hole states were comfortably large.
We have calculated double differential cross sections of(d,3He) reactions on 208Pb at T=600 MeV leading todeeply bound pionic atoms and also to unbound pionicstates, where T is the incident deuteron kinetic energy.
In a previous publication, we have developed theeffective number approach for the formation of deeply
bound pionic atoms in (d,3He) reactions . I) The
previous publication should be referred to for all thedetails. Figure 1 shows the results at 0 degree leading
to bound and unbound states as a function of Q value.
We find that a significant amount of strength comesfrom bound pionic atom states coupled with a neutron
hole state. On the other hand, the difference between thenegative pion spectrum and the neutral pion spectrum isremarkable as can be seen by comparing the 1C and nO
curves. The negative pion spectrum increases rapidly at
the threshold, whereas the neutral pion spectrum only
gradually increases from the threshold. This differenceis originated by the Coulomb interaction. Adding all
the contributions, we get the total cross sections as
depicted by the thick solid curve. It is very interesting
to note that the strength at Q =-130 - -140 MeV isalmost exclusively due to the bound pionic states. The
peak appearing at Q - -135MeV corresponds to the(2p)1t(3P3/2)n and (2p)1t(3P1/2)n configurations. We
also have calculated the double differential cross sections
at finite angles. The cross sections are smaller for larger
angles. Since the momentum transfer increases with thescattering angle, the (i13/2)n hole contribution isdominant at larger angles. 2)

100 - - - - - - - - - - - - - - o degree

80

:;Q,)

~
~
.D

60

<I)

0

'"'

u

·s

40

20

O'----.....c:...=....--..........;::~
-130
-150
-140

Q[MeV]
Fig. 1. 208pb(d,3He) reaction cross sections calculated
within the effective number approach leading to deeply
bound pionic atoms and quasi-elastic pionic states at
T=600MeV, 0 degree. The thick solid line means thetotal contribution of pionic processes. The experimental
energy resolution is assumed to be 100 ke V.
In conclusion, we have calculated the cross sections of
208Pb(d,3He) reactions in both the bound and unboundpion regions. We have found a large difference in thethreshold behavior of neg~tive and neutral quasi-freepion production cross sections due to the large Coulombinteraction. We also find that the cross section at Q =130 - -140 MeV does not include the quasi-elastic pion
contribution and the cross section is due to the boundpionic states.
References
1) S. Hirenzaki, H. Toki, and T. Yamazaki: Phys. Rev.,
C44, 2472 (1991).
2) S. Hirenzaki, H. Toki, and T. Yamazaki: in preparation.

* Inst. for Nuclear Study, Univ. Tokyo.
-47-

RIKEN Accel. Prog. Rep . 26 (1992)

111-1-40. Relativistic Mean Field Theory and Skyrme Hartree-Fock Theory

for U nstable Nuclei
K. Sumiyoshi,* D. Hirata, H. Toki, and H. Sagawa[Relativistic mean field theory, Skyrme Hartree-Fock theory, unstable nuclei.]
We make comparison of the relativisic
mean field theory (RMF) and the Skyrme
Hartree-Fock theory (SHF) for unstable nuclei. It
is getting demonstrated that the RMF theory
with the parameter set NLl describes not only
stable nuclei 1) but also unstable ones2) in a widemass region. The RMF theory wi th NL 1 isapplied also for the astrophysical use byproviding the equation of state of nuclear matterat various conditions}) On the other hand, theSHF theory has been in use for a long time for the
study of nuclear structure. It is, therefore, very
interesting at this moment to see the similarity
and the difference of these two frameworks incomparison with the existing nuclear data,
anticipating many new data coming in the near
future from the unstable nuclear beam facility.
All the details of the two models aredescribed in the recent publication by the present
authors. 4) Comparing first the nuclear matter
results, we find that the incompressibility of
RMF is slightly smaller than that of SHF, while
the symmetry energy of RMF is larger than thatof SHF. These features are reflected in the
behaviors of the equations of state for nuclear
matter and neutron matter around the normal
density. A striking difference is, however, in the
behaviour of EOS at higher density, where theEOS of RMF becomes much stiffer than that of
SHF. We note also that the EOS of SHF with themost popular Skyrme paprameter set SIll is not
acceptable for the astrophysical use, since theEOS of neutron matter becomes softer than that ofnuclear matter.
We choose several proton magic nuclei up to
the drip lines for comparison. It is very
interesting to observe that the drip lines are
predicted much closer to the stability line in RMF
than those in SHF. The binding energies arefound similar in comparison with the existing
data. It seems RMF gets better in heavier nuclei.
The proton radii are descibed extremely well by
RMF. At the same time, the neutron radii are
predicted much larger than the proton radii of

If-

Dept. Phys., Tokyo Metropolitan Univ.

- 48 -

the same nuclei as the nuclei deviate from thestability line. This existence of a large neutron
skin is revealed in the recent unstable nuclear
beam experiments for the He-isotope. 5) It would
be very desirable to measure the neutron radii for
nuclei far from the stability line.

R rms
n~

~------------------------------------------------------------~

[fm]
5.5

Sn
n

5.0
p

4.5

4.0 '---_ _....L.....-_ _- ' - -_ _---L-._ _---<_---'

40

60

80

100

120 N

Fig. 1. The root mean square radii of Sn within
RMF(NL1[solid curve]) and SHF(SIII[dash-dotted curve],
Ska[dashed curve]) as a function of the neutron number incomparison with existing data which are shown by
closed circles for protons and by closed squares forneutrons.

References
1) Y.K. Gambhir, P. Ring, and A. Thimet: Ann. Phys,(N.Y.), 198, 132 (1990).
2) H. Toki, Y. Sugahara, D. Hirata, B.V . Carlson, and I.
Tanihata: Nucl. Phys., AS24, 633 (1991)~ D. Hirata, H.
Toki, T. Watabe, I. Tanihata, and B. V. Carlson: Phys.
Rev., C44, 1467 (1991).
3) K Sumiyoshi, H. Toki, and R. Brockmann: Phys. Lett.,
B276, 393 (1992).
4) K Sumiyoshi, D. Hirata, H. Toki, and H. Sagawa: Nucl.
Phys., A (1992), in press.
5) I. Tanihata, D. Hirata, T. Kobayashi, S. Shimoura, K
Sugimoto, and H. Toki: Phys. Lett., B289, 261 (1992).

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-41. Application of the Relativistic Mean Field Theory to Deformed Nuclei
D. Hirata, I. Tanihata, H. Toki, and P. Ring*[Deformed nuclei, relativistic mean field theory]
Recently it becomes possible to study experimentally the properties of nuclei far from thestability line, in particular those with excess
number of neutrons, through the use of radioactive
nuclear beams. A large field of research has thus
been opened. With this new technique, more dataof unstable nuclei are being available.
We are interested in studying theoreticallyunstable nuclei using the relativistic mean .
theory. The application of such a theory has
been demonstrated to be an excellent tool todescribe the ground state properties of stable
nuclei. 1) As an example, its application to
unstable nuclei using a spherical symmetry gave avery good agreement with the experimental data.

using the constant gap approximation. A
constraint was added to study the dependence ofthe binding energy on the amount of deformation.
When the axially symmetry was applied to Sr
isotopes, it was found that the deformation
changes drastically from one shape to the otherat mass A=97 ,reproducing the observed jump inradius and the E2+ energies (see Fig. 1 and 2).
From the comparison with the data, it was foundthat this jump is due to a sudden transition of thedeformation from an oblate to a prolate shape.

R rms rp[fm]

2)

We have extended it to deformed nuclei. The
pairing correlation was also taken into account

oO

o •

Sr

•

4.3 -

••
••

EfA

99

[MeV]

.....
0

5

~

•• 0 0

00

4.2

_

0

0

0

0···.•

••

•

•

00

loRMFI

0

.exp

-8.4

4.1

I

I

I

I

I

I

42 46 50 54 58 62 N
38
Fig.2.The rms radii of Sr isotopes as a function of
the number of neutrons N.
We believe that the present work provides animportant base to study and understand thestructure of nuclei far from the stability line andthe underlying physics of nuclei.
Part of this work is supported by the exchange
program between the CNPq-Brazil and theMinistry of Education of Japan.

-8.5

-8.6

-0.6

I

I

I

I

I

I

-0.4

-0.2

0

0.2

0.4

0.6 ~

Fig. 1. The dependence of the binding energy on theamount of deformation for some odd Sr nuclei. The
arrows correspond the minima choosen , showing
the jump of deformation at A around 97.

It

References
1) Y.K. Gambhir, P. Ring, and A. Thimet: Anr:t. Phys. ,2)

Physikdepartment der Technischen UniversiUit
Miichen.

-49-

198, 132 (1990).
D. Hirata et al., Phys. Rev. ,C44, 1467 (1991).

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-42. Equation of State in the 1/N Expansion of a Relativistic
Many-Body Theory
K. Tanaka, W. Bentz; and A. Arima*[EOS, 1/N expansion, relativistic many-body theory.]
The investigation of the equation of state (EOS)
for nuclear and neubon matter has been one of themost active fields in intermediate nuclear physics.
The knowledge of the EOS is required for the analysisof heavy ion reactions as well as for the understanding of stellar structure and evolution. Since theseapplications require the EOS at densities of several
times the normal nuclear matter density, the EOS's
based on relativistic many-body theory are powerful
candidates. The simplest and widely used version ofrelativistic models is the uw model. l ) However, it is
known that the EOS obtained in the Harbee (me anfield) approximation to this model is unreasonably
stiff.
In this paper 2 ) we investigate the EOS in the O'W
model including the higher order many-body correlations beyond the Hartree approximation. We employ
the 1/N expansion scheme (N is the number of nucleon species), which has been recently proposed 3 )as a useful method to compute the higher order corrections in the relativistic many-body theory. The
Harbee approximation is obtained as the leading order term in this scheme. We include the next-toleading order contributions, which give the RPA-typemany-body correlations. The essential role of thesehigher order terms to reproduce the saturation property of nuclear matter has already been revealed.3 )We find that the EOS becomes softer due to theinclusion of the higher order many-body correlations,bringing the results closer to the empirical informations. In Fig.1 we show the pressure of nuclear matter as a function of the density, comparing our result
including higher order terms (the solid curve) withvarious other EOS's: The dot-dashed curve shows
the result in the Harbee approximation, the dottedcurve is the EOS based on the nonrelativistic variational calculation,4) and the dashed curve is the phenomenological EOS modeled to give successful typeII supernovae explosions. 5 ) Around the normal density, the softening of our EOS is reflected by the incompressibility of 301Me V, which is close to the empirical value and should be compared with 456Me V
in the Harbee approximation. For high densities our
EOS is even softer than the nonrelativistic one, which

D.2IS

D.2D

~

0.16

II.

0.10

i

D.D6

D.DD

OJ!

0.4

D.S

D.S

p. (tm-'.lFig. 1. Pressure vs. baryon density for nuclear matter.
For the explanation of the curves, see the text.

becomes very stiff with increasing density due to theviolation of causality.
As an application, we compute the neutron star
structure based on our neutron matter EOS, integrating the Tolman-Oppenheimer-Volkofl" equation. 6)
We include also the p-meson contribution at the
Hartree level into our EOS to reproduce the empirical symmetry energy of 30MeV. We find that ourEOS can support the observed neutron star mass andgives the neutron star properties consistent with observations.
References
1) B. D. Serot and J. D. Walecka: "Advances in
Nuclear Physics", eds., J. W. Negele and E. Vogt,
Plenum, New York, 16, 1 (1986).
2) K. Tanaka, W. Bentz, and A. Arima: preprint(1992).
3) K. Tanaka and W. Bentz: Nud. Phy,., A540,
383 (1992).
4) B. Friedman and V. R. Pandharipande: Nud.
Phy,., AS61, 502 (1981).
5) E. Baron, l. Cooperstein, and S. Kahana: Phy,.
Rev. Lett., 55, 126 (1985).
6) S. Weinberg: "Gravitation and Cosmology",
Wiley, New York (1972).

* Dept. of Phys., Univ. of Tokyo.

-50-

RIKEN Accel. Prog. Rep . 26 (1992)

111-1-43. Fermi-Liquid Properties of Nuclear Matter in the 1/N Expansionof a Relativistic Many-Body Theory
K. Tanaka, W. Bentz; and A. Arima*[Relativistic Fermi-liquid theory, 1/N expansion, nuclear matter.]
In recent papers l - 3) we have investigated therole of higher order many-body correlations in therelativistic uw model, based on the 1/N expansion
method. Our results have suggested the importanceof the higher order effects beyond the Barbee approximation to reproduce the bulk properties of nuclear matter, like the saturation property and theequation of state, deduced from various experimental informations. In this paper3) we analyze theseresults for nuclear matter from the more fundamental aspect of the elementary excitations (quasiparticles) and their mutual interactions. We employ thegeneral framework of the Landau theory of Fermiliquids. 4 ) One essential advantage of the Landau theory is that it provides rigorous relations between thebulk properties of matter and a few universal parameters characterizing the properties of the quasiparticles. Therefore, it allows a deeper understanding of
the results obtained in the preceding works.
Following the Landau theory, the quasiparticle
energy and the quasiparticle interaction are obtainedby taking the first and the second variational derivatives of the energy density of nuclear matter with respect to the quasiparticle distribution function. Since
our energy density includes the exchange and thering energy contributions of the next-to-Ieading orderin the 1/N expansion as well as the leading Hartreecontributions, our quasiparticle energy and quasiparticle interaction involve the corresponding higher order contributions; for example, those for the quasiparticle energy correspond to the RPA-type nucleon
self-energies.
We find that the quasiparticle spectra as wellas the quasiparticle interactions are largely modified
due to the higher order effects, and these modifications bring the results for the nuclear matter properties closer to the empirical ones. In Table 1 weshow the quasiparticle properties and the relevantbulk properties of nuclear matter for normal density. We see that the Fermi velocity VF is reduced
due to the higher order effects. For the quasiparticle interactions, they are reduced for the isoscalar
channel (Fo, F 1 ) while non-zero values are generated
for the isovector channel (F~, Fn. It is the combined
effect due to the reduction of both VF and Fo thatmakes the incompressibility K considerably smaller
compared to the Bartree approximation, through the
rigorous relation4 ) K
3PFvF(1 + Fo) with PF the=Fermi momentum.
As an application, we investigate the collective
excitations (sound waves) of nuclear matter on thebasis of the Landau kinetic equation. 4 ) We find thatthe reduction of vp, Fo and F1 noted above leads tothe softening of the isoscalar sound modes.
Table 1. Quasiparticle properties and bulk propertiesof nuclear matter at normal density. "lIN" refers to
our full result including the higher order contributions,while "Hartree" refers to the Hartree approximation.
The numbers in parenthesis show the Hartree contributions contained in the full result. Shown are the ratioof the nucleon effective mass to the free nucleon mass
M· 1M, the Fermi energy E'p, the Fermi velocity 17F, thedimensionless Landau parameters Fo, Fl , FJ, F:, the incompressibility K, the first sound velocity Cl, the symmetry energy 44, and the isoscalar and isovector orbital
angular momentum g-factors g~O) and g~l). Empiricallyknown values are K ~ 200
300MeV, 44 ~ 30MeV,
g~O) ~ 0.52, and g?) ~ 0.56. (E'p - M = -15.7MeV isused as an input to determine the parameters of ourmodel.)
I"'J

I/N

M·/M
€F -

M [MeV]

vp

Fo
F1

F.'0
F'1
K [MeV]C1
a4 [MeV]

(0)

g,
(1)
g,

0.894
-15.7
0.289
0.356
-0.113
0.189
0.096
301
0.190
14.7
0.509
0.545

(0.894)(17.7)(0.292)( -0.593)(-0.247)
(0.0)
(0.0)
(91.5)(0.103)(12.5)(0.491)(0.535)Hartree
0.730
-15.7
0.350
0.691
-0.621
0.0
0.0
456
0.234
15.0
0.509
0.641

References
1) K. Tanaka and W. Bentz: Nucl. PhY6., A540,
383 (1992).
2) K. Tanaka, W. Bentz, and A. Arima: This report,
p.SO.
3) K. Tanaka, W. Bentz, and A. Arima: preprint.
(1992).
4) L. D. Landau: SOv. PhY6. JETP, 3, 920 (1956);
ibid., 5, 101 (1957); ibid., 8, 70 (1959).

·Dept. of Phys., Univ. of Tokyo.

-51-

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-44. A Modified Nambu-Jona-Lasinio Modelfor Mesons and Baryons
M. Kato,* W. Bentz,* K. Yazaki, and K. Tanaka[Baryons, UA(l) anomaly, NJL model.]Hadrons are now believed to be composite particles composed of quarks and gluons, whose dynamics
are governed by quantum chromodynamics (QeD).
Since it is very difficult to handle QeD directly at
low energies, eff'ective theories are often used to study
hadron physics. In the energy scale of hadrons, QeD
has two important properties, spontaneous chiral symmetry breaking and confinement, which should beincorporated into these models as much as possible. The Nambu-Iona-Lasinio (NIL) model l ) is oneof these eff'ective theories. In this model mesons
can be described as quark-antiquark bound states
through the spontaneous chiral symmetry breaking.
One drawback of this model is that it does not incorporate the confinement. We can expect, however,that the difference between binding and confinement
has no serious consequences as long as we limit ourselves to the description of the ground state.
Recently,2> it has been suggested that in the
Hartree approximation to this model there also exists a baryon-like solution as a solitonic bound statewith three valence quarks. In this paper 3 ) we reexamine the existence of this soliton solution towarda unified and consistent description of mesons andbaryons. We use the modified flavor SU(3) NJLmodel,4) which incorporates one more important property of QeD, Le., the axial U(1) (UA (1» anomaly,
as well as the flavor SU(2) model used in Ref. 2.
We find that in the flavor SU(2) case there exists
no stable solitonic solution. The solutions spread or
collapse according to the value of the coupling constant of the 4-fermion interaction, and this situation
does not change even if we include the vector-type
interaction which is expected to stabilize the system. In the flavor SU(3) case we can obtain stable
solutions. The stabilization comes from the flavor
mixing with the strange-quark due to the "instanton
induced" 6-fermion interaction describing the UA (I)anomaly. As shown in Fig. 1, the flavor mixing leads
to a position-dependent (density-dependent) eff'ec-·Department of Physics, Univ. of Tokyo.

- 52 -(ss)

Fig.!. The contribution of the 6-fermion interaction, whichleads to a position-dependent efl'ective coupling constantof the 4-fermion interaction GD{'i.). GD is the coupling
constant of the 6-fermion interaction, and (i'.) is thestrange-quark condensate which is position-dependent forthe solitonic state.

tive 4-fermion coupling constant, which in turn gives
a repulsive effect near the origin of the solitonic state.
In order that this mechanism prevents the collapse, we need an appreciably larger flavor mixing
compared to the previous works.4) We show that thislarge flavor mixing does not lead to inconsistencies
for the physical quantities, by examining the physical observables of the nucleon and also by investigating the properties of the pseudoscalar mesons inthe same framework. One of the reasons for this ist he compensation by the rather small values for thequark condensates of our solution.
References
1) Y. Nambu and G. Iona-Lasinio: Phy,. Rev., 122,
345 (1961); 124, 246 (1961).
2) Th. Meissner, F. Griimmer, and K. Goeke: Phy,.
Lett., B227, 296 (1989).
3) M. Kata, W. Bentz, K. Yazaki, and K. Tanaka:
NucZ. Phy,., A, in press.
4) T. Hatsuda and T. Kunihiro: Z. Phy,., C51, 49(1991).

RIKEN Accel. Prog. Rep. 26 (1992)

III -1-45. Faddeev Approach to the Nucleon in the
Nambu-Jona-Lasinio (NJL) Model
N. Ishii,· W. Bentz,· and K. Yazaki[NJL-model, faddeev theory']
The NJL model 1) has been quite successful in describing the mesons as qq bound states. 2) In recent
years, it has also been used to investigate baryons,
where mainly the mean field approximation 3) andthe diquark-quark model 4) have been used. The
Faddeev approach which takes into account the interaction between the diquark and the quark was recently used by Buck et al , 5) employing a static approximation to the quark propagator and restricting
the 2-body channels to the scalar diquark one. In
this work we solve the relativistic Faddeev equation
6) numerically in the scalar diquark-quark channel
without any further approximation.
Our calculations are based on effective quark interaction Lagrangians £[ with 4-fermion coupling of
the NJL-type. If we try to construct the nucleon as
a bound state of a scalar diquark and a quark, thedependence of the results on the actual form of £[comes in only through the ratio r = g,d where g1r is
g1r

the strength of the interaction in the pionic (0-) q7jchannel which is fixed by the pion mass, and g,d isthe one in the scalar (0+) qq-channel. We will study
the baryons with the ratio r as a parameter. We
require that our calculation reproduces the experimental values of the pion mass and the pion decay
constant. This leaves us with one free parameter,
and we actually treat the constituent quark mass related to the other parameters by the gap equation as
this free parameter, investigating mainly the cases
M = 350,400MeV. As mentioned before, we treat
the ratio r as a further parameter. We solve the relativistic Faddeev equation using the quark-quark Tmatrix obtained from the two-body Bethe-Salpeter
equation as an input. We calculate the maximum
eigenvalue >'(E) of the Faddeev kernel as a functionof the total C.M. energy E, and the baryon mass isobtained from >.( mB) = 1. Here we confine ourselvesto the nucleon.
The maximum eigenvalue >'(E) for the case M =400Me V is shown in Fig.1 as a function of E for differ. r = '2'
1 3"
2 08
1 Th ere eXIsts.
. .
ent ratIOS. ,.
a mInImUm

t.1 = 400MeV
1.2

1.0

0 ,0
II>
;:l

OJ

>
~

iJ

0.4

0,2

0 ,0
0 ,2

0,6

0 ,0

1.2

Fig.I. The maximum eigenvalue of the kernel asa function of the total energy E for several ratios r for the case of constituent quark massM = 400MeV. The vertical dotted lines represent
the quark-diquark thresholds for each ratio. A
3-body pole exists if the graph intersects the horizontal dotted line, and the coordinate of the intersection is the baryon mass.
This could serve as a guide for the search of an interaction Lagrangian which is able to describe bothmesons and baryons. We also compared our exact solutions with the results of the static approximation of
Buck et al, where the mass of the exchanged quark is
virtually treated as infinitely heavy. We found thatit could be used to obtain qualitative estimates, but
quantitatively it gave too much attraction. Finally
we mention that for more quantitative investigations
we have to include at least the axial vector diquark
channel in addition to the scalar one.

References

It follows that we cannot get a bound nucleon statewith the original NJL-Lagrangian for which the ratio

6.5

0.4

Total e n ergy E [CeV]

ratio r for three quarks to be bound which in our
calculation is about 0.5 in the case of M = 400MeV.

r is ~

0 ,6~

In order to get a reasonably good nucleon

mass, the ratio should be about ~ for M =400MeV.

* Dept. Phys., Univ. Tokyo.
-53-1) Y.Nambu and G.Jona-Lasinio: Phys. Rev., 122,
345 (1960); 124, 246 (1961).
2) T.Hatsuda and T .Kunihiro: Z. Phys., C 51, 49(1991).
3) M.Kato, W .Bentz, K .Yazaki, and K.Tanaka,· A
Modified N ambu-Jona-Lasinio Model for Mesons
and Baryons: Nucl. Phys. , A, in press.
4) U.Vogl and W.Weise: Prog. in Part. and Nucl.
Phys., 27,195 (1991).
5) A.Buck, R.Alkofer, and H.Reinhardt: Phys. Lett.,
B 286, 29 (1992).
6) G.Rupp and J.A.Tjon: Phys. Rev., C 37, 1729
(1988); C 45, 2133 (1992).

RIKEN Accel. Prog. Rep. 26 (1992)

III -1-46. Nuclear Transparency in (e, e' p) and (p, 2p) Reactions
A. Kohama,* R. Seki,** and K. Yazaki[Nuclear transparency, Glauber approximation. ]It has been speculated!) that the internal structure of hadrons may show up in quasi-elastic processes with nuclear targets at large momentum transfer. More specifically, the nuclear medium may become anomalously transparent for a hadron before
and/or after a hard collision, since the strongly localized configuration with the smallest number of constituents in the wave function describing the internal structure of the hadron contributes dominantly
to a hard process and a hadron in such a configuration is expected to interact weakly with the nuclear
medium.
The nuclear transparency,2) T, in the electron
quasi-elastic process, (e,e'p), is defined by the ratio between the differential cross section for nuclear
target, daeA/dO, and that for e-p elastic scattering,
daep/dO, as
1 daeA /da ep
dO

Z dO
where

daeA
dO =

= F(k)T(q)Jk,2 dk , dp dacA(27r)3 (27r)3 dk'dp

where p( r) is the nuclear density for the target normalized to unity and aNN is the nucleon-nucleon reaction cross section. This is the same as the semiclassical estimate with the proton mean-free-path except that the total cross section is replaced by thereaction cross section. A similar expression is obtained in the case of the proton quasi-elastic process,(p,2p), where the initial state interaction for the incident proton as well as the final state interaction forthe outgoing protons has to be included in the attenuation factor.3) The results for both cases with 4He,
12C, 16 0, 27 AI, 63Cu and 208Pb as the targets are
given in Table 1. The kinematical conditions correspond to those of the experiments by Carroll et al. 4 )in the case of (p, 2p) reaction and the same is taken
for the case of (e, e' p) reaction. ar.m in this energy
region is essentially constant and therefore the transparencies do not depend on the incident energy. The
magnitudes of T for (p,2p) are roughly consistent
with the observed ones, although the energy variation indicated in the experiment is not reproduced.
Table 1. The calculated transparencies.

with k, k' and p denoting the incident electron, thescattered electron and the knocked-out proton momenta, respectively, F( k) is the kinematical factor
including the Fermi averaging and q is the average
momentum of the knocked-out proton. T(q) approaches 1 as the nuclear medium becomes transparent for the knocked-out proton.
We have calculated T(q) in the Glauber approximation without considering the internal structureof the proton which is to be compared with the experimental value for testing the above idea. With
the assumptions which are better justified for heavier targets, we have obtained a simple expression for

T(q), i.e.

T(q) =J

drp(r) exp { -Ao-NN

1,= p(z',dz'PbtargetT(e, e'p)T(p,2p)

0.51

0.68
0.35

0.59
0.25

0.51
0.17

0.11

0.28
0.046

Referencesr.L)}*Dept. Phys., Univ. Tokyo.
**Dept.Phys., California State Univ .• U.S.A.

-54-1) S.J. Brodsky: Proc. 13th Int. Symp. on Multipartide Dynamics 1982, ed. by W. Kittel, W. Metzger
and A. Stergiou, World Scientific, p.963 (1982);
A.H. Mueller: Proc. 17th Recontre de Moriande(Les Ares, 1982) ed. by Tran Thanh Van, p.13 Ed.
Fron tiers, (1982).
2) A. Kohama, K. Yazaki, and R. Seki: Nucl. PhY8. A,
in press.
3) A. Kohama, K. Yazaki, and R. Seki: Nucl. PhY8.,
A536, 716 (1992).
4) A.S. Carroll et al.: PhY8. Rev. Lett., 61, 1698
(1988).

RIKEN Accel. Prog. Rep. 26 (1992)

111-1-47. Chiral Symmetry Restoration inside Flux Tubes of Hadrons
H. Suganuma[Chiral symmetry restoration, finite-size effect, confinement.]
Hadrons can be considered as string-like tubes
from the empirical evidences of the Regge trajectory
and the duality of hadron reactions. We have studied
the manifestation of chiral symmetry and the hadronstructure based on this picture. 1) Recently, several
authors have indicated that the finite-size effect may
be important for the study of the ij-q pair creationby the Schwinger mechanism,2-5) which is theoretically related to chiral symmetry. 1) Hence, we study
the finite-size effect on the manifestation of chiralsymmetry inside the :flux tube of hadrons in terms of
the Nambu-Jona-Lasinio (NJL) model, an effective
theory of QCD.
We regard hadrons as ideal cylinders with a radiusR, and impose the linear boundary condition for thequark field. When the pion field outside tubes is neglected, the effective action is simply separated into
the radial and longitudinal parts, 5) so that the numerical calculation becomes possible for it. Figure 1
shows the numerical result for the dynamical quark
mass in the :flux tube with the cylinder radius R,

chiral-symmetry restoration takes place for the small
radius R ~ 0.45 fm.
We also investigate our subject in the presenceof the external color-EM field. Both a color-electricfield and the finite-size effect contribute the chiralsymmetry restoration ad ditively. Hence our previous result on the chiral-symmetry restoration inside
hadrons 1) is not qualitatively changed even if we include the finite-size effect of hadronic tubes, although
the critical field strength Eer is reduced.
Finally we make a physical interpretation of ourresults. The spontaneous breakdown of chiral symmetry (XSB) is induced by the strong coupling in
the low- momentum region because of the asymptotic freedom in QCD. This mechanism is effectively
included in the NJL model: XSB is induced by astrong effective interaction between quarks in the
low-momentum region below the ultraviolet cutoff.
When the system is confined in a tube with thecylinder radius R, long wave components of quarks
are forbidden in the direction vertical to the cylinder
axis, so that an infrared cutoff of the order R-I appears in the corresponding momentum space of thequark field. Such reduction of the strong-couplingregion would weaken the nonperturbative effects on
XSB, and lead to the chiral-symmetry restoration fora small R.

when a color-electromagnetic (color-EM) field is assumed to be absent. The dynamical quark mass isfound to be reduced by the finite-size effect, and the400. 0 r---""""I""--~---'T--""T"""---'

300.0

200.0

100.0

o

0.25

0.50

0.75

1.00

1.25

R[fm]
Fig.I. The dynamical quark mass as a function of
the cylinder radius R, when the color-EM field isassumed to be absent. Calculation is done in thechirallimit.

References
1) H. Suganuma and T. Tatsumi: Phys. Lett., B269,
371 (1991).
2) C. Martin and D. Vautherin: Phys. Rev., D38,
3593 (1988); Phys. Rev., D40, 1667 (1989).
3) R. C. Wang and C. Y. Wong: Phys. Rev., D38,
348 (1988).
4) Th. Schonfeld, A. Schafer, B. Miiller, K. Sailer,
J. Reinhardt, and W. Greiner: Phys. Lett., B247,
5 (1990).
5) H. P. Pavel and D. M. Brink: Z. Phys., C51, 119(1990).

-55 -RIKEN Accel. Prog. Rep. 26 (1992)

111-1-48. Chiral Solitons at Finite Temperatures
H. Suganuma[Chiral solitons, properties of baryons at finite temperatures.]We study properties of baryons at finite temperatures using the Skyrme soliton model. l ) The Skyrme
model, an effective theory of the pion field, seems to
be one of the most suitable candidates for this subject because the lightest hadrons i.e. pions play animportant role at low temperatures. A baryon is described as a soliton of mesons in this model, so thatthe thermal effect for the baryons is brought by thethermal fluctuation of mesons around the soliton.
By introducing the pion fluctuation ¢J around thestatic soliton solution, one gets the Lagrangian of ¢J
in the presence of the background field of the static
soliton.!} The partition function at finite temperatures is derived from the path integral Z by using
the imaginary-time method. One obtains the thermodynamic potential in terms of soliton profile byintegrating out the ¢J-field in Z. Since the original Skyrme model is an effective theory up to thefour-derivative terms with respect to the derivative
expansion, it would be reasonable to drop off thehigher-order derivati ve terms by using the technic ofthe derivative expansion. 2 )After some complicated calculation, a finite expression of the thermodynamic potential n is obtained besides the temperature-independent irrelevant constant. It is noted that the symmetric fourderivative term appears in n at finite temperatures,
however, its coefficient is rather small in comparison
with that of the Skyrme term at low temperatures,e.g., T .:S f 70' It is also found for the expression of nthat the pion decay constant f~ and the Skyrme parameter e seem to be effectively modified as f:(T) =
2
2
1 Tl
70
T'*]l/2
e*(T) -- e[l+ 90e:l
70r.!.]-l/2
f 70 [1 - 6.fl- 4Se:l I f 'n
at finite temperatures. The effective pion-decay constant f:(T) is reduced by the thermal effect, which
may be interpreted as the chiral symmetry restoration at high temperatures. 3 ) On the other hand, only
a little reduction is found for the effective Skyrme parameter e*(T) as long as the temperature is not sohigh.
One gets the hedgehog-soliton mass MH at finite
temperatures from the thermodynamic potential n.
Since the nucleon and the delta can be regarded asadiabatically rotational solitons in this model, theirmasses can be obtained by the collective-coordinate
method. I) The numerical results for the baryon
masses are shown in Fig.I. The delta mass Mf). is.
--_.._.._
1200.0

...

Ml!!.

~

-.. .....'-.

' ..........

1100.0.............

1000.0 ------------------- ---~-

900.0 -

800.0~o______~·______~~____~
0.5
1.0

T[!1r]
Fig.I. Temperature dependence of baryon masses forthe delta, the nucleon and the hedgehog soliton.

largely reduced by the thermal effect. While, lessmodification is found for the masses of th~ hedgehog
soliton and the nucleon. Then the mass difference
between the nucleon and the delta becomes smaller
at finite temperatures. One also finds that the sizeof hedgehog soliton is monotonously increased by thethermal effect. Such tendencies on the baryon properties at finite temperatures can be easily understoodin terms of the behavior of J;(T) and e*(T).
In the solid state physics, it is known that thethermal effect reduces the soliton mass and enlarges
the soliton size in the 1+1 dimensional sine-Gordon
system. 4) Hence qualitatively similar features arefound on the mass and size at finite temperatures
between the chiral soliton and the sine-Gordon soliton.

References
1) For the recent review, Prog. Theor. Phys. Supplement, 109, 1 (1992).
2) r. J. R. Aitchison and C. M. Fraser: Phys. Rev.,
D31, 2605 (1985).
3) J. Gasser and H. Leutwyler: Nucl. Phys., B307,
763 (1988).
4) K .Maki and H.Takayama:Phys. Rev., B20, 3223
(1979).

-56-

RIKEN Accel. Prog, Rep, 26 (1992)

III -1-49. Chiral-Syrnrnetry Restoration in a Strong Color-Electric Field
and Hadron Structure
H. Suganuma and T. Tatsumi*[Chiral symmetry restoration, hadron structure.]
Recently much effort has been devoted in order tounderstandhadronsandnonperturbative
QCD vacuum in terms of quarks and gluons. As
is well-known, the spontaneous breaking of chiralsymmetry is one of the most important features in
the low-energy realm of QCD. Commonly valencequarks or antiquarks are often introduced and play
an important role in analyses of the hadron structure. Here we study how the color-electromagnetic
field formed by valence quarks affects the properties
of QCD vacuum inside hadrons in terms of the manifestation of chiral symmetry. 1,2)
We study our subject based on the Nambu-JonaLasil;lio model, an effective model of QCD. For thecovariantly constant color-electromagnetic field, we
can derive the compact formula of the effective potential. Its real part denotes the energy of vacuumwith each value of (qq), the order parameter of chiralsymmetry breaking. We can derive the Dyson equation for the dynamical quark mass from the minimum condition for the real part of effective potential. On the other hand, its imaginary part denotes
the Schwinger formula for the q-q pair creation.
We solve the Dyson equation in the presence of theexternal color-electric field that valence quarks would
form, and obtain the dynamical quark mass as thefunction of E == J6tr c (gE)2 'as shown in Fig.L The
lower two lines denote the dynamical u,d-quark massin Fig.1 : the solid line corresponds to the empiricalcase with a non-vanishing current quark mass, while
the broken line corresponds to the chiral limit. The
upper line denotes the dynamical s-quark mass. One
finds that the chiral-symmetry restoration occurs bya strong color-electric field, and the rapid reductionof the dynamical (u,d- )quark mass is found aroundthe critical field strength, Eer =::: 4GeV /fm. 1 ,2) As forthe s-quark mass, only a moderate decrease can beseen in comparison with the u,d-quark mass. 2 )Based on the color-electric fiux-tu be picture forhadrons, 3) one can evaluate the color-electric fieldstrength as
5.3 '" 6GeV/fm(> eer) inside
hadrons from the empirical value of the Regge slope(see the shaded region in Fig.1). Therefore our result
suggests that the chiral-symmetry restoration woulde=take place inside the flux tube due to the strong
color-electric field formed by valence quarks. i,2) It
is interesting that this result may lead to the chiral bag picture for hadrons: the chirally-symmetricphase exists inside the flux tube, while chiral symmetry remains broken outside the flux tube wherecolor fields are absent.
In order to get deeper insight of our results, it isalso desirable to refer different approach such as lattice QCD simulations. In recent years, an Austriangroup has found the reduction of the ·quark condensate (qq) around valence quarks or the color sources
by using lattice QCD simulations, 4) which agrees
with our results qualitatively.

MD[MeV]
500.0~--

400.0
300.0
200.0
100.0

o

chiral limit

2.5

5.0

7.5

& [GeV/fm]
Fig.1. The dynamical quark masses as functions ofE (magnitude of the color-electric field).
References
1) H. Suganuma and T. Tatsumi: Phys. Lett., B269,
371 (1991).
2) H. Suganuma and T. Tatsumi: preprint KUNS,
1091, p.1 (1991).
3) A. Casher, H. Neuberger and S. Nussinov: Phys.
Rev., D20, 179 (1979).
4) W. Burger, M. Faber, W. Feilmair"and
H. Markum: Nucl. Phys., A525, 581c (1991).

* Department of Physics, Kyoto Univ.
-57-

RIKEN Accel. Prog. Rep. 26 (1992)

III-I-50. Large-scale Numerical Simulationof the Three-state Potts Modelt
S.Ohta[Potts model, quantum chromodynamics, parallel computer.]
Lattice numerical calculations of pure-gauge quantum chromodynamics (QCD) revealed that at a finite temperature the system undergoes a first-orderphase transition from a low-temperatur~, disordered,and color-confining phase to a high-temperature, ordered, and non-confining phase. The phase transition is driven by the global 23 symmetry which manifests itself through the Polyakov line order parameter. The transition is weak in the sense the latent
heat is small and the Polyakov line correlation length
grows. The existence of a first-order phase transition
and its weakness seem common among the systems
with the global Z3 symmetry such as the three-state
Potts model. It is not yet understood, however, why
the phase transitions are so weak. The author investigated this problem through his numerical simulation of the three-state Potts model on three dimensional simple cubic lattices. I)
Earlier numerical simulations of the model established a first-order phase transition separat.ing a lowtemperature ordered phase and a high-temperaturedisordered phase . It' is considered weak because thelatent heat is small. However, the small volumes
caused frequent flip-flop transitions between the twophases and it was hard to tell in which t.he system
resides at a given instant. Consequently, the naturesof the individual phases could not be studied, nor
the reason why the phase transition is so weak. The
author overcame this difficulty by the vastly larger
volume of 128 3 that became feasible by a parallel
computer AP1000 of Fujitsu laboratory,2)
The two-point correlation function, Cij (1'), definedas the probability to find a pair of spin i and j separated by the distance 1', is numerically calculated ineach of the two phases around the phase transition .
In both of the phases the correlations are found to
decay exponentially in Yukawa form as the distance l'increases toward infini ty (Fig, 1). Such behavior was
known for the disordered phase but not for the ordered phase. The correlations between the like spinsare always attractive and those between the unlike
spins are usually repulsive with one exception. Accordingly, clustering of like spins is observed in bothphases, with the sizes consistent with the correlation
length of several lattice spacings,
The exception is the correlation bet\,veen the twodifferent non-favored spins in the ordered phase: it

0.05
0.04
0.03
0.02
0.01

o

-0.01
-0.02
-0.03
-0.04
-0.05

o

2

4

6

8

10

Fig. 1. Correlations in the ordered phase near thetransition. The curves are the best fits to Yukawa
form for ranges above 3, The favored spin is O.

is short-range repulsive but long-ra.nge attra.ctive.
The range of attraction appears much longer, at a
few ten lattice spacings, than the others . Such along-range attraction between the two different nonfavored spins is likely to cause instability of the ordered phase. In the corresponding spin distribution one finds that clusters of the two different nonfavored spins appear within neighborhood of eachother. It should be noted that this is an efficient way
of maintaining the global 23 symmetry, and is prob.
ably a direct consequence of the symmetry. 3). I t IS
also found that such clusters do not have smooth surfaces, but have complex concave boundaries. Thus
the neighborhood of such a cluster of clusters of thenon-favored spins can be considered as an island of
the disordered-phase left in the sea of the orderedphase. Such admixture of the disordered domains
into the ordered phase gives a natural explanation of
why the phase transition is so weak.
References
1) S. Ohta: in Proc. Int'l Symp. "Lattice '92,"
Amsterdam, the Netherlands, September 15-19,
1992, Nucl. Phys. B (Proc. Suppl.), to be published, and references cited there in.
2) S. Ohta: in Proc. Int'l Symp. "Computing
in High Energy Physics '92," Annecy, France,
September 21-25, 1992 , to be published.
3) S. Ohta: in preparation.

fThis work was supported in part by Parallel Comput.ing Research Facility, Fujitsu Laboratory, who provided computing
time on their APIOOO parallel computers.

-58-

2. Atomic and Solid-State Physics

RIKEN Accel. Prog. Rep. 26 (1992)

111-2-1. Production of Inner-Shell Vacancies in Energetic Ar Ions

Penetrating Solid Targets
Y. Zou, Y. Awaya, T. Kambara, Y. Kanai, M. Qura, Y. Nakai,
K. Ando, A. Hitachi, and S. Kravis
Inner-shell vacancy production in heavy-ion
atom collisions is expected to be caused by the
direct Coulomb ionization or electron promotion via quasi-molecular orbits. Generally the
Coulomb process is dominant when the atomic
numbers of the collision partners are much different or the collision velocity vp is higher thanthe orbital velocity of the active electron Ve' On
the other hand, the electron promotion is dominant when vp is smaller than Ve'
We studied the K-shell vacancy production
processes of Ar ions by collisions with various
atoms in a velocity region between those of thedirect Coulomb and the electron promotion processes (vpJv e1). We have made systematic
measurements of the intensity ratio between the
Ka-X rays from double K-vacancies (hypersatellites) and those from single K-vacancies of projectile Ar ions excited by penetration of solid
targets. The ratio reflects the magnitude of Kshell vacancy production probability. The target
atomic number Zt ranged from 6 to 73, and thetotal kinetic energy of the Ar ions ranged from43 to 300 MeV, which corresponds to 0.43 ::;vpJ Ve ::; 1.13.
We used an Ar 8 + beam from the RILAC inexperiments at 43, 52, 65, 80.3, and 95 MeV,1)and Ar 5 + from the RIKEN Ring Cyclotron at
300 Me V. The beam was directed on various
metallic foil targets. The Ka- X rays emitted
from the beam incident side were measured bya broad-range crystal spectrometer. 2 )Figure 1 shows the intensity ratio at 43 and300 Me V as functions of Zt. The ratio has oscillatory behavior with two maxima at each incident energy. The positions of the maxima changewith the incident energy: At lower energies, they
are located at Zt=22 - 26 and Zt=50 - 60, and atenergies higher than 80 MeV, they are locatedat Zt=26 - 30 and Zt=60 - 70.
At collision energies higher than 80 Me V, themaxima in the ratio are reproduced by the calculation with Born approximations. At lower
energies the maxima shifts to small Zt, and at

10
0

0

0

cu

a:

CO

0

o~

0

~

0
<Z)

en

-

300 MeV• 43 MeV
0
0

0
0
0

C

Q)

.:
~

.1

......

N
~

••

• ••

.01

0

20

•

..'

• •

.,

40
60
Target Atomic Number (Zt)

80

f'V

Fig.

1. Ka-X ray intensity ratio of transitions
from double K-vacancies to those from single Kvacancy of Ar ions in various targets wi th atomic
number Zt. The energy of Ar ions are 300 MeV(upper) and 43 MeV (lower). '40 MeV they nearly correspond to the enhancement of the K-vacancy production by electron
promotion process. The results show a gradualchange of relative importance from the electron
promotion to the Coulomb process according to
the increase of the collision energy. In the intermediate energy region, the K-vacancy production cross section increases with the collision velocity, but the increase rate is much different
among the targets.
A theoretical work to treat the K-shell vacancy production in this velocity region is reported elsewhere by Naitoh et al. 3)
References-59-1) Y. Zou, T. Kambara, Y. Kanai, Y. Awaya, K.
Ando, M. Ohura, A. Hitachi, and S. Kravis:
RIK£H , Accel. Prog. Rep., 25, 69 (1991).
2) A. Hitachi, H. Kumagai, and Y. Awaya: Nucl.
Instrum. Methods 195, 631 (1982).
3) Y. Naitoh, Y. Zou, T. Kambara, Y. Awaya andK~ Fujima~ This rep~rt. p.80.

RIKEN Accel. Prog. Rep. 26 (1992)

111-2-2. Measurement of RER X Rays from 0.8 MeV/nucleon Ar Ions
Excited by a Foil
M.Oura, T.Kambara, Y.Kanai, S.D.Kravis, Y.Zou,
Y.Awaya, and J.Palinkas
We have previously reported a measurementof the KL3 RER (Radiative Electron Rearrangement) x rays from 0.8MeV/nuc1eon Ar
ions excited by a target foi1. 1) The KL3 RER
process is a correlated two-electrontransition 2 - 4) and x rays are produced by anelectron rearrangement from an initial configuration 1s22s22p3 to a final one 1s22so2p4, where
superscripts are the number of electrons ineach subshell. Here we report an analysis of
the data. The values of the intensity ratio R3
between the KL3 RER and the KuL3 satellite
were estimated by a least-squares fitting
procedure with Voigt functions. The extracted
values are shown in table 1 for C and Al foil
targets, where those are compared with thetheoretical values. 4) The present intensity
ratios are smaller than the typical experimental
values obtained from the target atom excitation 3,4) and those are smaller than theory by afactor of 16.6 for the C target and 4.8 for the
Al target.
Two 2s electrons are necessary for the RER
processes. The reason for the weak KL3 RER
intensity in projectile ions can be explained bya large population of 2s vacancies in the ionswith a K-vacancy since the value of intensity
ratio is proportional to the square of the 2s-2p
mixing coefficient in the final state. 3,4)
The projectile Ar ions in a target material
quickly reach an equilibrium charge state distribution through successive outer-shell collisions. The equilibrium mean charge state of
O.8Me Vlu Ar ions in the carbon foil used wasabout 11.5 and the mean number of the Mshell electrons is less than unity.5) It meansthat the mean number of the L-electrons of Ar
ions in target is about 4. If these electrons are
distributed statistically among the L-subshells,
the probability having two 2s electrons isabout 0.2 and it results in the small intensity(by a factor of 5) of the RER transition inprojectile Ar ions relative to the RER intensity
via the target atom excitation. The measurement of the RER x rays gives us information
about the 2s-2p electronic configuration of theinitial state, therefore we can expect that it canbe a tool for study of the electronic configuration of L-subshells of fast ions in a medium.
Further experiments are in progress.

Table 1. Intensity ratio (KL 3 RER/KaL3) R3 exp .•Projectile

TargetAr

C

Origin of KL3 RER

R3..,.n(7.5 ± 2.5) x 10-4 •(R3'h,onr /R 3 I'In.)
16.6#

ProjectileAr

Al(2.6 ± 0.8) x 10-3 •

4.8#

C,N

Mg

(1.34 ± 0.33) x 10.2 $

0.96

H-O

Al

(8.5 ± 2.1) x 10.3 $1.43

Target(1.37 ± 0.18) x 10.2 $Si* Present data.
$ Data from Ref.3.
# (R3 theor J value was for Ar ions without M-shell electrons.

H-CI

0.85

3) K.A. Jamison et al. :.Phys. Rev., A14, 937 (1976).
4) T. Aberg et al.: Phys. Rev., AIS, 172 (1977).
5) T. Mizogawa et al.: Phys. Rev., A42, 1275 (1990).

References
1) M. Ohura et al.: RIlffiN Acce!. Prog. Rep., 25, 70(1991).
2) K.A. Jamison et al.: J. Phys., B8, LA58 (1975).

-60-

RIKEN Accel. Prog. Rep. 26 (1992)

111-2-3. Measurements of RER X Rays from 37 MeV/nucleon Ar Ions
Excited by a Carbon Foil
T. Kambara, Y. Awaya, Y. Kanai, M. Qura, S. Kravis, and Y. Zou
The radiative electron rearrangement (RER)
process is described as a radiative transition witha simultaneous rearrangement of two electrons. I)
We have studied the RER process in fast, few
electron systems through a high-resolution Xray measurement.
In many cases, RER is much weaker thanthe corresponding Ka satellite transitions, andthe relative intensity of the RER to the satellite tr ansition yields information on the configuration mixing in the excited state. However,aLi-like Is2s2 state is a special case in whichradiative decays are limited through the RER
process. If one Is electron is ionized from a Belike ion in a ground state (ls22s2) by a collision and the other electron configuration is notchanged, the excited state has a configurationof Is2s2 which decays only through the RER to
the Is22p state. Therefore we can estimate thefraction of the Is2s2 state among the Is-vacancy
states by measurements of RER and Ka-X rays.
In the experiment, a beam of Ar 14 + (Be-like)at 36.6 Me V /nucleon from the Ring Cyclotron
impinged on C foil targets with thicknesses of 10,
22, 39, and 85 f-Lg/cm 2. Since the energy of the
RER X-rays in aLi-like Ar ion is about 3.04 ke V
which is lower than the K-X rays of the Be-likeions by only 30 e V, the X rays were measured
by a broad-range crystal spectrometer. Besides
the X-ray spectra, we measured the charge state
distribution of the ions which passed the sametargets and compared the target thickness dependence of intensity of each 0 bserved X-ray linewith that of the charge state distribution. The
charge state distribution of the ions was measured with a magnet and a position sensitive
PPAC (Parallel Plate Avalanche Counter) behind the target.
Figure 1 shows an X-ray spectrum for the
10 f-Lgfcm 2 target. A peak at around 3.11 keY
is from Kasatellite transitions from Is2sm2pn
to Is 22s m2 p n-1 configurations in Ar 15 + (Li-like;
m=l,n=1 or m=0,n=2) and Ar 16 + (He-like;m = 0, n = 1) ions, and a shoulder at about 3.08

3

3.1

3.2

3.3

X-Ray Energy (keV)
Fig. 1. Spectrum of K-X rays of Ar ions penetrating
a 10 fJ,g/ cm2 thick carbon foil.

ke V is from those in Ar 14 + (Be-like; m + n =3, n 2:: 1) ions. Some weaker peaks around 3.3
ke V are from the states with double Is vacancies.
A small peak appears at about 3.04 keY which
agrees with the expected RER X-ray energy, andthe intensity of the peak is smaller than a few %of that of the satellite lines of Ar 15 +. However, it
is also possible that the peak is from Kasatellite
transitions in Ar 14 + since some transitions fromthe triplet or quintet states of Ar 14 + have energies close to this region and the intensity of thepeak decreases with the target thickness in asimilar way to the fraction of ArI4+. Therefore,
from this measurement, we cannot tell whether
this peak is the RER X-rays from the Li-likeAr 15 + ions or low-energy satellite transitions of
Ar14+. Even if the peak is the RER- X rays, thesmall in tensity means that Ar 15 + ions after thetarget have only a small fraction of the configuration Is2s2 among the Is-vacancy states.
References-61-1) M. Ohura, T. Kambara, Y. Kanai, S. D. Kravis,
J. Palinkas) and Y. Awaya: RJ££H Accel. Prog.
Rep., 25, 70 (1991).

RIKEN Accel. Prog. Rep. 26 (1992)

111-2-4. Coincident Charge States Distributions of Recoil andScattered Ions in 26 MeV Ne-Ne Collisions
S. Lencinas, T. Kambara, S. Kravis, Y. Kanai, M. Oura,Y. Awaya, M. Terasawa, and H. Schmidt-Bocking
Differential cross sections for the production ofhighly charged recoil-ions (du( 0, qf, q~, qR)jdO) havebeen measured for collisions of 26 MeV Ne 4+,7+ with
Ne and He targets using a coincidence technique,where 0 is the projectile laboratory scattering angle, qr the incoming projectile charge state, q~ theoutgoing projectile charge state, and qR the recoil
ion charge state. qo ranges between 3 and 6 and qR
between 1 and 8. Ionisation probabilities P( 0) coincident with different recoil ion charge states wereextracted for the different reaction channels like single, double and triple electron loss as well as single
electron capture of the projectile.
A Ne 4 + beam from the RILAC was collimated overa total length of 4 m to obtain an angular resolu tion
~O ~ 0.1 mrad. Having passed through a differentially pumped gas cell the projectiles were chargestate analysed and after a flight path of 7 m detected with a position sensitive PPAC (Parallel Plate
Avalanche Counter). The recoil ions prod uced in thegas cell were extracted with an electric field, driftedin a field free region, and were detected with a channeltron detector. A standard coincidence technique
was used between the signals of the PPAC and therecoil ion detector. The different recoil ion charge
states were separated in the time-of-flight spectrum.
The P( 0) for different reaction channels were obtained by dividing the specific single differential crosssections by the total elastic scattering cross section.
The scattering angle corresponds to an impact parameter region between 5.10- 2 and 5.10- 1 au. This
covers the relevant impact parameter range for Ne
K-shell ionisation accompanied by multiple ionisation of the L-shell.
Figure 1 shows the obtained [PC O)]:~ for different
recoil Ne charge states and single electron loss of the
projectile. The probabilities show clearly the different impact parameter contributions to the different
Ne recoil ion charge states. At large impact parameters (b > 0.5 au) the low charged recoils dominate
the charge state distribution. The principal mechanism in this range is the direct ionisation by the projectile. With decreasing impact parameter, higher
charge states are produced. In this case, K-hole production is enhanced via Auger decay to the observed
recoil-ion charge state. 1 )Screenings of the projectile charge was investigatedby changing the initial projectile charge state. For
the single capture channel, Fig. 2 shows the target ionisation probabilities for Ne 4 +,7+ as a projec-

10 2

x

0

0

x

1()1

0
)()

¢

0
0

~

,.

¢

10 0

0
0 09:
000
XO
x ~
¢ x
~ ¢
¢
0
o
¢
0

8

q)

P:'

o
+

10- 1

+ +

+

10- 2
0

0.5
scattering angle 8 (mrad)Fig. 1. Target ionisation probabilities [P( 8)]:~ fordifferent recoil Ne charge states. Symbols: 0 Ne2 +,x Ne 3 +, ¢ Ne·+, 0 Nes+, and + Ne 6+

Ne4+ +Ne->Ne s++Ne ll +

10 0

~

0
0

III

!E

~

,. 10- 1

Cj

q;-

~

P:'
10- 2

o

!E

mi

~ If I

0.5
scattering angle 8 (mrad)Fig. 2. Comparison between the ionisation probabilities
by Ne·+ and Ne 7 + as projectile for the single capturechannel. Symbols: 0 Ne 7 + and + Ne·+ projectile.
tile. At small scattering angles (0 ~ 0.2 mrad) an
increase of the ionisation probability by a factor of
30 is observed for Ne 7 + projectiles and high recoilion charge states, while in the large scattering angle
range (0 ~ 0.5 mrad, b ~ 0.1 au.) the appreciable
difference vanishes within the error bars.

References-62-1) H. Sharabati, K. Bethge, J . Ullrich, R. Dorner R .
E. Olson, V. Dangendorf, R. Koch, and H . SchmidtBocking: J. Phys. B, 23, 2957 (1990) .

RIKEN Accel. Prog. Rep. 26 (1992)

111-2-5. Multiply Charged Ions Produced from Gaseous and Condensed
CO Targets under Energetic Ion Impact
H. Tawara, T. Tonuma, H. Kumagai, and T. Matsuo

Various secondary (recoil) ions haveber~ produced under the 1.5 MeV/amu
Ar + ion impact on condensed CO tarfJt
using an apparatus already described.
A typical mass/charge spectrum of ionsfrom a condensed CO target is shown in
Fig.1(B), to gether lith that fromgaseous CO targets 2 (Fig.1(A». In
these spectra we can see the following
features :a) In gaseous targets, the parent CO +ion yields are larger by an order ofmagnitude compared with dissociation
product C+ ion yields, whereas bothare comparable i"n condensed targets.
b) In condensed targets, C+ ion yields
are an order of magni tude larger than0+ ion yields. Meanwhile, they areroughly equal in gaseous targets.
c) In condensed targets 0+ and O ion
yields are smaller compared with C+
ion yields.

2

CO target
10 5

10

4

co·

,(A)gaseous
C··

10 3

0"

c"

I
c" a" I

I 0"

c' o'
co"

0"

10 2
..J
I.il

f/'

~ 10 1

«
u

'I

:I:

;n 10°
f- 10 4Z:::>
0, , .,
,I
I

u
10

I

:

, I

,,

3

102

101

(B) condensed
256

CHANNEL NUMBER

Fig.l.Mass/charge spectra of multiply
charged secondary ions from (A)gaseousand (B) condensed co targets.

d) Doubly charged parent molecula§ C0 2+
ion yields are very small (10- ofCO+) in condensed targets, whereas
they are about 4 %. in gaseous tarfets.
e) Multiply charged C1+(i~5) and 0 1(i~6) ion yields are observed incondensed and gaseous targets. It isnoted that intensity ratios of theneighboring charge (1+1/i) for highi are roughly the same for both
gaseous and condensed targets.
f) In condensed targets, cluster C andC; ion yields are roughly comparable
to those of C+ ions (see Fig.1(B».
On the other hand, no cluster ion isobserved in gaseous targets.

2

These features in condensed moleculetarget:s-",can be understood quali tati velyin comparison with those in gaseous
molecular targets~) Namely, multiply
charged atomic ions gain large initial
kinetic energies which depend on theion charge states at the time of dissociation of multiply charged molecularions. Indeed, their kinetic energies
are of the order of a few eV-a few t usof eV for ions in the present system 2J.
On the other hand, Jhe recoil energy isa few hundreds meV~ This difference of
the initial kinetic energies results inthe observed significant variations .
It is concluded that yields of multiply charged C1 + and 0 1 + ions including
H- and He-like ions have been found to
be much larger in condensed CO gas targets compared with those in condensed
rare gas targets such as Ar.
References
1) H.Tawara,T.Tonuma,H.Kumagai, andT.Matsuo:J. Phys. B 25,L423(1992).
2) T.Matsuo,T.Tonuma,M.Kase,T.Kambara,
H. Kumagai" and H. Tawara: Chern. Phys. .
121,93(1988).
3) H.Tawara,T.Tonuma,K.Baba,T.Matsuo,
M.Kas~,T.Kambara,H.KumagaL and I.
Kohno;Nucl.Instr.Meth.B23,203(1987).
4) R.E.Olson,J.Ullrich) and H.SchmidtBBcking;J.Phys. B 20,L809(1987).

-63-

RIKEN Accel. Prog. Rep. 26 (1992)

111-2-6. Measurement of Ejected Electron from Quartet State of
N 4 +** (183131') Created by N6+ + 02 Collisions
T. Negishi, N. Nakamura, S. Kitazawa, M. Nagata, S. Ohtani, T. Takayanagi, K. Wakiya,
H. Suzuki, Y. Kanai, T. Kambara, and Y. Awaya
Since the last five years our group has measured
ejected electrons from the doubly excited state created byhighly charged ion - atom collisions. I )We are now interested in ejected electrons from amultiplet state. In the last year we chose the triplet stateof Q4+**(1s2313/'), (:4+**(3131') , by using 02 as thetarget gas. 2 ) And this year we carried out themeasurement of electrons ejected by N6++H2 andN6++02 collisions. Collisions with H2-gas are rather
simple system, because a H2 -molecule has twoelectrons that give a singlet state as the ground state, sothat the multiplicity of any incident ion is not changedin the collision process if an incident ion captures boththe electrons of a H2-molecule. In this work, an ejected
electron from the excited state N4+**(l s3131') is the
doublet state in the N6+ +H" collisions, and it is in theN6++0 2 collisions the do~blet or the quartet state.
Therefore it is expected that we could have some
informations of the quartet state of N4+**(l s313l') if
we compare obtained two spectra.
We measured following prosseses,

-'-c
I tl

=
...

.Q

~

>
Eo-

.....

00

Z

~

Eo-

Z
.....
15

25

30

35

40

ELECTRON ENERGY (eV)Fig. 1. High-resolution spectrum of ejected electron fromthe doubly excited N4+ (ls3131') ions produced in
N6+ - H2 collisions.

-I tl

'c

=

.Q

N6+ + H2 ~ N4+(1 s3131') + 0 22+

L

20

...

~

>
Eo-

N5 +(1 SII "/") + e

.....
en
Z

~

EoZ
.....

15

Figures 1 and 2 show examples of the obtained
spectra. Incident ions are generated by the ECR Ion
Source. Collision energy is 60 ke V and observation
angle is 0 degree with respect to the incident ion beam.
Comparing these two spectra, we can find some different
features in Fig.2 from that in Fig. 1. By the N6+ - H2
collision, only doublet states are created. On the other
hand, by the N6+ - 02 collision quartet states are also
possibly created in addition to doublet states. Therefore
we assume that the difference between these two spectra
is mainly caused by quartet state of N4+. Unfortunately
we could not assign these peaks. For further discussion
we need more theoretical calculations.

20

25

30

35

40

ELECTRON ENERGY (eV)Fig. 2. High-resolution spectrum of ejected electron fromthe doubly excited N4+ (1s3131') ions produced in
N6+ - O:z collisions.

References-64-1) H. A. Sakaue, Y. Awaya, A. Danjo, T. Kambara, Y.
Kanai, T. Nabeshima, N. Nakamura, S. Ohtani, H.
Suzuki, T. Takayanagi, K. Wakiya, I. Yamada, andM. Yoshino: J. Phys., B24, 3787 (1990).
2) T. Nabeshima, N. Nakamura, S. Ohtani, T. Takayanagi,
K. Wakiya, H. Suzuki, A. Danjo, M. Yoshino, Y.
Kanai, T. Kambara, and Y. Awaya: RIKEN Accel.
Prog. Rep., 25, 77 (1991).

RIKEN Accel. Prog. Rep. 26 (1992)

111-2-7. Binary Encounter Peaks for ·0° Electrons in Collisionsof 0.8 MeV/nucleon Bici + with H2 and He
Y. Kanai, T. Kambara, M. Dura, Y. Zou, S. Kravis, and Y. Awaya
We present the charge-state dependence on the binary
encounter peaks in collisions of 0.8 MeV/nucleon Biq+on H2 and He measured at zero degree, in the region of~/Zl < 0.4. In this collision system, the binary encounter peak intensity increases as the charge state increases.
The peak energy of the binary encounter peaks is shiftedto energies lower t~an E b ( binary encounter peakenergy for free electron targets) and this shift value
increases as the charge state increases. The charge state
dependence of the intensity is in good agreement with
the CTMC calculations by Schultz and Olson. 1) The
peak energy shift is explained qualitatively by the
Bohr-Lindhard mode1. 2)The experiment was performed at RILAC. The beamof Bi10+,14+,32+ from RILAC was magnetically analyzed,
collimated by two sets of four-jaw slits system andfocused to the target gas cell. The target gas cell was 5
em in length. Single collision conditions were verified
experimentally.
Ejected electrons were measured at zero-degree
respect to the beam direction. The spectrometer was atandem type electron spectrometer with two 45° parallel-plate electrostatic analyzers.
In our collision system and the collision energy, theincident charge state dependence of the binary encounter electron intensity was "normal" ; the intensity increases as the incident charge state increases. According to the CTMC results, if we use high enough charge
state Bi ions, we can observe the "anomalous,,3,4) charge
state dependence( the intensity decreases as the incident
charge state increases ) and also the change from the"normal" dependence to the "anomalous" dependence.1
But, we could not use high enough charge states ( q.1 >40 ) to observe this.
The q.1 dependence of the energy shift of the binary
encounter peaks can be explained by the Bohr-Lindhard
model. Details of this model were reported in ref. 2.
Here, we describe it briefly. In this model, there is acharacteristic distance R r( the release distance). Whenthe projectile ions come to this distance, target electrons
are released from target atoms because of the balance
between the forces from the projectile ions and thetarget atoms. After that, the released electrons collidewith the proj ectile ions as free electrons. Based on thismodel, the energy shift ~b from Eb is given byHere, q.1 is the incident charge state, I t the ionization
potential of the target, 10 the ionization potential of thehydrogen atom, and Zz the target atomic number. Z)
Pedersen et al. used this formula to evaluate the energy
shift for the fully stripped ion case. Z) But, if the Rr islarger than the radius of the c1othed(partially stripped)
proj ectile ions, it is applicable for the clothed proj ectile
ion case. 3) Calculated shift values ~b for our collisionsystem are also shown in table 1. In our case, the Rr for
Hz targets are vIO, v14, and v32 a.u. for Bil0+, B i14+,and Bi3z+, respectively. The radius of the outer electron
orbit of Bi lO+,14+,3Z+ ions is 1-0.5 a.u. Our assumptionthat Rr is larger than the radius of projectile ions is not
so bad in our system.
Table 1. Binary encounter peak shift for 0.8 MeV/nucleon Bi
ions on H2 and He target.
He
projectile
exp
Bi 1O+
14t

Bi
Bi 32+

136±20132±20220±30peak shift(e V)
Bohr-Lindhard
exp Bohr-Lindhard
172
203
308

216±40212±40300±40

239
283
427

References
1) D. R. Schultz and R. E. Olson: l. Phys. B24,3409(1991).
2) 1. O. P. Pedersen, P. Hvelplund, A. G. Petersen and P. D.
Fainstein: l. Phys. B24,4001(1991).
3) P. Richard, D. H. Lee, T. J. M. Zouros, J. M. Sanders, and
1. L. Shinpaugh: l. Phys. B23, L213(1990).
4) P. Hvelplund, H. Tawara, K Komaki, Y. Yamazaki, K
Kuroki, H. Watanabe, K Kawatsura, M. Sataka, M. !mai,Y. Kanai, T. Kambara, and Y. Awaya: l. Phys. Soc. lpn.,
60,3675(1991).

-65-

RIKEN Accel. Prog. Rep. 26 (I 992)

111-2-8. Search for -MeV Electrons Produced by 95 MeV/nucleon

Ar Ions Bombarding C, Ni, Au Foils
Y. Yamazaki, K. Komaki, T. Azuma, K. Kuroki, K. Kawatsura
Y. Kanai, T. Kambara, M. Ohura, and Y. A waya
The energy and angular distributionsof o-electrons emitted in 95MeV/
nucleon Ar17+ ions bombarding C, Ni, andAu foils have been measured with RIKEN
Ring Cyclotron. As had been reported1 ),electrons in the energy range of -MeV
were observed with a surprisingly highcross section (-10- 24 cm 2 ) . In the present report, we discuss a new experiment
which has been done to confirm the previous observations. For this purpose, amagnetic sector analyzer was constructedwith an electron detection
assembly
consisting of an MCP followed by aplastic scintillator. Such a combination was adopted to make sure that anelectron with the right energy and theright trajectory was detected. Note that
the MCP is so thin that -MeV electrons
penetrate the MCP and hit the scintillator at the same time.
Figure 1 shows a new result measured
at 0° for 95MeV/nucleon Ar17+ bombarding
a 100 jJ. g/cm 2 carbon foil together
with the previous data measured with adetector assembly consisting of fourfold surface barrier detectors (SSD),
each
having a depletionlayerof-500jJ. m.
We have again obtained
similar results, i.e., the higher energy
tail appears in the same energy range
with an intensity of the same order ofmagnitude.
A possible explanation of such a highenergyelectronisaninternal
conversion of excited nuclei.
However,
we have found that the r -ray production cross section in the same energy
range is only -10- 23 cm 2 • As a typicalinternal conversion coefficient of thepresent collision system is10- 3 -10- 5 ,thecontributionof aninternal
conversion is of minor importance.
calA non-relativistic 1st Born
CUlation was performed to get an orderof magnitude estimate of a typical cross

-25

10

I

........

~

'Vl

~

- 16

('.IE

27 l-

u
-......;

-

"C
-0

Ni

\
\
1\
1\
\

,

I'

-

A

/~\.'...... ... , U

-

c-~,

-

~~

... ~

W

- 1029

I

I

-0

('.Ib

-

I-

-0

,
0

I

1

I

Elect ron Energy (MeV)2

Fig.1. Doubly differential cross sections
d2 a /dEdQofelectronproduction as a function of electronenergy measured at 0° with a magnetic
sector analyzer (solid line), and at
45° with a four-fold SSD detector1)(dashed line) for 95MeV/u Ar17+.
section of electron production. It isfound that the single differential crosssection for 95MeV/nucleon Ar18+ bombarding a 1s-electron of carbon foil ismore than 7 orders of magnitude smaller
than those observed.
Summarizing, we have reconfirmed astrong electron emission in an -MeV
range, which is neither attributable toa usual atomic collision process nor to
an internal conversion process. Further
experimentsarein progresstoinvestigate
the origin of the0electrons.
References1} Y.Yamazaki et al.: RIKEN Accel. Prog.
Rep.,~,54 (1990).

-66-

RIKEN Accel. Prog. Rep. 26 (1992)

111-2-9. Beam-Foil Experiment of Neonlike Iron
K. Ando, Y. Zou, T. Kambara, M. Oura, Y. Nakai, Y. Awaya,
and T. Tonuma
We continue the measurements of lifetimes of Nelike isoelectronic sequence. Following Ti and Cr, westart to measure Ne-like Fe. Before the measurementsof decay curves, spectra of Fe ions were taken from 250

A to 450 A with the spectral resolution of about 0.5 A
for the acceleration energy of 46, 58, and 73.5 Me V,

FE 58MEV A
..-f

0-

C

..-f

('I')

a
V)

"0

C""')

C""')

I

I

0.-4

c..

V1

Ii
..

:1.:

C""')

C""')

,....

.

Lt)

Lt)

Cl
C""')

c..

C""')

~

\0

\0
\0

0"1

C""')

C

I

C""')

\0

..-f

C
C""')

c..

C""')

.
,....
\0

Lt)

-- -- ->
><

x

QJ

Q.I

Q.I
LL.

LL.

LL.

N

>

N

>
x

Q.I

LL.

~"O

N

"0

I

>
><

N

C

". .-f

C""')

N

N

LL.

"0

N

C""')

~

N
LL.

C""')

C""')

.-4

.-4

Ii'

LL.
C""')

"0

I

ii

N

..-f

c..

C""')

N

Cl

LL.

I

"0

"0

C""')

C""')

I

i c..

C""')

C

.. cvo

C""')

C""')
i
C""')
: c:::>-4 ~ c..

i ~:: c:::>-4~

ilcxxx:>

i ~1
l~ L
;~,

:»:1

co

(lJ

c..

C""')

.
_.

~

0'1

co
co

N

N

>

>

- -

i><><1: ><1

N
0C""')

I
..-f

0..

: C""')

M

C""')

x

Q.I

LL.

: ~ .

""""''''O__ ~''''''''''''''''CIO-''-''''''O''''''''''''... "'''''''''''''''''.......... CIOCIO,..,...0.... -'"'''-... CIOI\IOO\'''~_.... ,.,-CIO"""-~... "',., ...... "'~CIO'" "'CIO ......
-"' ....... ''''''~'''CI00ClO-OClO-"O\Ol\l<OC\lO"'CIO .... ...."'~-O... ...-O"'''''''''''''''O&I''I''''''''''OI\ICIO-..o....-o 0",-...
... ,.,0",~~w-\"'~~o\Q-:"=~"; ~~~~o"": ~,.;~~~~~cOo\OO...:~...;..;"'~,v..:~Q..:..:.~~.;"'~~o\oo~..;~~~ ~'1io\o\~'117~~~'" ~~'q''V:.fW\I,tlI.t\t.n

II\t/Y.I\"'~\()\O\0\0\0\0\0'0\00 \Q\Q\O~ ~,..,,"",..,,:-...:-........."""'"'Z) C:OCl)Q')Q)QlQ) CO<I:)CX)COQ;)<I) QJO\O\O\O\O\O\O\O\O\O\'0\ C\O\Q\""""''''''''''t\$\.~''''''''''''''''''~'''''''''''''''''''''''''''''' ...~'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''~'''''''''''''''''''''

Fig. 1. Part spectrum of Iron ions with identified spectral lines of Fe XVII.

and spectral lines of Ne-like Fe (Fe XVII) wereidentified according to the reference 1. Intensities oflines of Fe XVII were strong at the acceleration energyof 58 MeV, as estimated from the semi-empiricalformula?) Observed spectrum is shown in Fig. 1 with
the identified spectral lines of Fe XVII.

-67-

References
1) J-P. Buchet, M-C. Buchet-Poulizac, A. Denis, 1.
Desesquelles, M. Druetta, S. Martin and J-F. Wyart:
J. Phys., B20, 1709 (1987).
2) K Shima, N. Kuno, M. Yamanouchi and H. Tawara:
At. Data and Nucl. Data Tables, 51, 173 (1992).

RIKEN Accel. Prog. Rep. 26 (1992)

111-2-10. X-ray Studies on Muon Transfer Reactions

from Hydrogen to Helium
K. Ishida, S. Sakamoto," Y. Watanabe, T. Matsuzaki, and K. Nagamine
Muon transfer reactions from muonic hydrogens
to helium nuclei are of practical importance inthe muon catalyzed fusion (J!CF), since helium
atoms are accumulated in a d-t mixture due to thetritium decay as well as the nuclear fusion. In thisprocess, a hydrogen-helium muonic molecule isformed. 1)
HJ!+ He -> HHeJ! -> H + HeJ! (H: p, d, or t)
The hydrogen-helium mesomolecule is in an
excited state when formed, then is deexcited to aground state quickly, emitting 6.8 keY X-ray.2)
Recently it was theoretically proposed thatthe excited hydrogen-helium muonic molecule
has another decay mode. It may decay into ahydrogen and a muonic helium without emitting
an X-ray and the transition energy is dissipatedas kinetic energy}) This radiationless decay rate
was calculated to be comparable to that of theradiative decay and have strong dependence on
the isotopes of hydrogen and helium.
We observed X-rays from d 4HeJ..l., d 3HeJ..l., andp4HeJ! molecules in liquid protium or deuterium
where a small admixture of helium was dissolved
by charging helium gas into the target cell. 4) The
experiment was carried out at the pulsed decay
muon channel of the Meson Science Laboratory of
J1.- In D2+4He{2.0alm) 747000 spills

h~k~::.:~i;J~ ~Energy [keY]

in D2+3He(2 .0alm} 1192000 spillsJ).-h::r(kW~~.::: :iJ
1..

0:.!: ~

00

•

10

II

"

D

Energy [keY]

J.L - in H2+4He(2 .0alm) 952000 Spills

Fig. 1. Observed X-ray energy spectra for the threesystems: D2+4He, ~~He, and H2+4He.

l<

the University of Tokyo, located at KEK. X-rays
were observed with a Si(Li) detector. The
intensities of X-rays were found to decrease as thenuclei get lighter as in Fig. 1. In Table 1, themeasured yields were compared with thecalculated yields, where the helium
concentrations were estimated from the Henry's
lawS) and the theoretical values of the molecularformation rate1) were used.
Our measurement was consistent with thecalculations which include the radiationlessdecay mode of hydrogen-helium muonic
molecule. The result is still preliminary and weare planning to do further measurements forconfirmation.
Table 1. The observed and calculated relative yields of
6.8 keV X-rays normalized to those of d4He)l.
Muonic Molecule
Helium Atomic
Concentration [ppm]Observed X-ray intensity
Calculated X-ray intensity(without radiationless decay)
Calculated X-ray intensity(with radiationless decay)

267

191

785

1
1

0.123
±0.0190.206

0.002±O.019
0.035

1

0.096

0.007

References
1) Yu.A. Aristov et al: Sov. J. Nucl. Phys., 33, 564(1981). A.V. Kravtsov et al.: J. Phys. B: At. Mol.
Phys.,19, 2579 (1986).
2) T. Matsuzaki, K. Ishida, K. Nagamine, Y. Hirata
and R. Kadono: Muon Catalyzed Fusion, 2 (1988)
217.
3) Y. Kino and M. Kamimura: contribution tointernational workshop on muon catalyzed fusion,
Uppsala, Sweden (1992).
4) S. Sakamoto et al.: to be appeared in UT -MSL
Newsletter, ed. K. Nagamine, No. 11 (1992). K. Ishida
et al.: contribution to international workshop on
muon catalyzed fusion, Uppsala, Sweden (1992).
5) P.C. Souers: Hydrogen Properties for Fusion Energy,
University of California Press, Berkeley, p.190(1986).

University of Tokyo.

-68-

RIKEN Accel. Prog. Rep. 26 (1992)

111-2-11. Measurement of Isotope Shift of Molybdenum by
Resonance Ionization Spectroscopy

H. Katsuragawa, T. Minowa,* M. Kubota,* and H. Komatsu**
I n a pre v i ous repor t we presented apulsed heating method for providing
atomic beams of metal elements. J) We
have studied the resonance ionization
spectroscopy (R IS) of a Mo atomic beam
produced by the pulsed heating method.
Mo atoms were ionized resonantly by apulsed dye laser tuned to the Z 7P 3 a 7 S:l transi tion of Mo.
Because the bandwidth of the pulsed
laser (0.6 G Hz in HWHM) is rather
broad to measure the isotope shift of Mo,
we separated each isotope by a mass separator and observed their resonance ioni za t i on spectra. T he seven isotopes of
Mo were separated by a two-stage acceleration TO F mass spectrometer. Figure
1 shows a T 0 F spectrum of Mo ions.
The mass resolving power was about 200,
which was sufficient to measure the isotope shift of each Mo isotope.
o bserved widths of the R I S spectraof each Mo isotope were 0.8 G Hz in
H W H M. T he line shape of the spectrum
was fitted to a gaussian curve. The peakfrequency of the spectrum was deduced by
the least- squares method. Figure 2 shows
the measured isotope shift, where the difference of peak frequency between 92Mo
and other isotopes is plotted against themass number.
The obtained isotope shift of Mo is ingood agreement with the result of Aufmuth
et al. 2) A Ithough several works on theisotope shift of Mo have been reported,
our work is the first one using the reson-ance ionization spectroscopy.
I n ourwork on I y a 200 f.1 g Mo filament was used
to measure the isotope shift of Mo.

40
Cf.)

fZ

0

u

z

:=:

98

95

92

~

20
100

20 . 25

19.16

TIME OF FLIGHT (/1 s)Fig. 1.

Time-of - flight spectrum of Mo ion.

T
1 GHz

1

92

¢

94

95

96

97

98

100

MASS NUMBER
Fig. 2.

Measured isotope shift.

References
1) T. Minowa, H. Komatsu, H. Katsuragawa,and T. I namura: If/IEA' AcceJ. Prog. Rep., 24.
58 (1990).

2) P. Aufmuth, H. P. Clieves, K. Heilig,
A. S teudel, and D. Wendlant: Z. Physik,
A 285. 357 (1987).

* Department of Physics, Toho University.
** Tokyo Gakugei University.
-69-

RIKEN Accel. Prog. Rep. 26 (1992)

111-2-12. Radiative Lifetime Measurement of Heavy Metallic
Ions in an RF Trap
Hyperfine Levels in the 3Pl State of Lu+
Y. Matsuo, H. Maeda, and M. Takami
Ion trap can confine ions for a long period of timeand can be combined with laser cooling that
reduces the kinetic energy of gaseous atoms andions. Laser spectroscopy in an ion trap is one ofthe promising techniques to determine thephysical quantities of stable and unstable nuclei
by measuring their isotope shifts and hyperfine
structures.
We have constructed a radio-frequency (RF) ion
trap that directly captures the ions produced bylaser a bla tion 1 ) . The laser ablation method isuseful for producing ions ·of heavy refractory
metals and is also expected to be particularly
suitable for generating multiply charged ions andrevaporizing implanted atoms containing
unstable nuclei.
We here report the lifetime measurement of Lu+
with the laser ablation-ion trap method byobserving laser-induced-fluorescence (LIF).
Linearly polarized light from a pulsed dyelaser pumped by a XeCI excimer laser irradiates
the central part of trap and the fluorescenceemission from trapped ions is focused onto a
photo-multiplier. The photo-electron signals areaccumulated with a gated integrator or with atransient digitizer synchronized with the dyelaser pulse. The former is used for frequency
d~main measurements and the latter for timeresolved measurements.
Lu+ ions are excited from the ground 150 state to

the 3P1 excited state. The spontaneous emission
to the 3D1,2 metastable states is observed. The
laser excitation fluorescence spectra have a
triplet structure caused by the hyperfine structurein the 3p 1 level. It is possible to record timeresolved LIF signals with a transient digitizer at
each peak of those triplet transitions. Lifetimes
are extracted by least-square-fitting of the decay
curve to a convolution of an exponential decay andthe laser pulse profile. Lifetimes of the three
hyperfine levels of Lu + 3P1 are shown in Table 1.
All three levels have almost identical radiative
lifetimes. Relatively longer decay times ofallowed transitions suggest weaker o scilla tor
strengths of Lu+ ion compared with alkali-earth
metal ions such as Ba+, for which lifetime of the2P3/2 level, 6.4 ± 0.6 ns, is obtained with this
instrument.

-70-

Table 1. Radiative lifetimes of the Lu +3Pl excited state
lifetime(ns)F level40.2 (1.3)
9/2

7/2
5/2

40.6 (1.8)
40.1 (1.4)

References
1) Y. Matsuo, H. Maeda, and M. Takami: Hyp. Int., inpress.

RIKEN Accel. Prog. Rep. 26 (1992)

111-2-13. 57Fe Mossbauer Studies of YBa2(Cul-xFex)40S
T. Okada and K. Asai
A high-Tc superconductor YBa2C\l40s (socalled 124 compound) with Tc=80 K, has attracted
much attention because its oxygen content isthermally stable up to 800°C. It has the similar
structure to a 123-superconductor, YBa2Cl13D7, but
the former has doubly stacked Cu-O chains, or aribbon, in place of single Cu-O chains of thelatter. Recently, 57Fe Mossbauer studies of
YBa2(Cu1-xFex)40s were performed in order toelucidate the mechanism of the superconductivity of the oxide. But there is acontroversy on the site occupation of Fe ions inthis compound,l,2) and the magnetic propertiesof Fe ions, especially their magnetic ordering andits effect on the superconductivity of the host,have not been clarified.
In this report, a 57Fe Mossbauer study of a 124superconductor YBa2(Cul-xFex)40s (x=0.018) at
various temperatures is made to elucidate the site
occupation of Fe ions in the 124-compound.
A powder sample was synthesized by a solidstate reaction using 02-HIP technique. The valueof Tc determined by the Meissner effect is 48 K.
The values of the isomer shift (l S) are given
relative to Fe metal.
57Fe Mossbauer spectra at 298 and 4.2 K areshown in Fig. 1. As shown in the Fig. 1 (a), thespectrum at 298 K can be analyzed as being
composed of two quadrupole doublets denoted by(a) and (b). The values of IS indicate that Fe ionsin (a) doublet are in trivalent state and those in(b) doublet are in tetravalent state. On lowering
temperature below 40 K (not shown in the figure),
the Mossbauer spectrum becomes broad and thenshows a magnetic splitting. As shown in fig. 1 (b),the spectrum at 4.2 K can be analyzed with twomagnetically split sextets denoted by (A) and (B)in the figure. The values of IS and population
indicate that sextets (A) and (B) are associatedwith Fe ions in the doublets (a) and (b),respectively.
The angle between the directions of Hhf and theprincipal axis (z-axis) of the electric field
gradient (EFG) in each site can be obtained from

298 K

(a)

~

~

c
o

88

'(j)

en

'E 100
en
c

~
I-

98

(B),........~...........
(A)

-10

4.2 K

---L--I----L---l~

1..-1

0
+10
Velocity (mm/s)

Fig. 1. 57Fe Mossbauer spectra of the specimen with
x =0.018 at 298 and 4.2 K.

the analysis of the spectra at 4.2 K. The principal
axis of EFG in Cu(2) sites is different from that in
CuO) sites. Then we can assign the site occupationof Fe ions in the compound.
It is concluded that the major part of Fe ions is intrivalent state and occupies the Cu(2) sites, andthe minor is in tetravalent state and occupies theCU(l) sites. They are magnetically ordered at
low temperatures, meaning that the superconductivity of Cu(2) ions and the magnetic orderof Fe ions coexist in the Cu(2)-O plane. It should
be noted that long range exchange interactions
beyond the neighboring Cu(2) ions cause themagnetic order because the content of Fe ions is as
low as 0.018.
References
I) FeIner et al.: Physica C 185-189 (1991) 1117.

2) P. Boolchand et al.: Phys. Rev. B 45 (1992) 921.

-71-

RIKEN Accel. Prog. Rep. 26 (1992)

111-2-14. Muon-Induced Luminescence in KBr
R. Kadono, A. Matsushita, K. Nishiyama,* and K. Nagamine

Ion implantation techniques are of basic
importance to the study of condensed matter for
applications in which radiative nuc1ei(inc1uding
muons) are used as microscopic probes: theygreatly facilitate the use of those probes for awide range of materials without limitations due
to surface effects, their solubility, the interaction
between probes, and so on. Relatively little is
known, however, about the deexcitation process of
the implanted energetic probes in solids near orat the final stage when they might be affected by
the existence of excitons or defects induced by theprobe ions themselves. In most cases it has beencommonly assumed that the probe ions are instantaneously degraded to thermal energy in solid
specimens and that the associated excitations in
crystalline solids are short-lived or dilute enoughfor such a radiolysis effect to be negligible.
We report on the luminescence induced bypositive muons implanted (with 4 MeV) into KBr
crystal, which evidences a long-lived (lifetime =13.3 Jls) excited state produced by muonradiolysis.1) The temperature dependence of theluminescence yield has a strong correlation withthe occurrence of "anomalous" muonium center(Mu I )2): both are observed only below 50 K (seeFig. la). This correlation strongly suggests that,
contrary to the above presumption, the muonium
center is perturbed by the muon-induced excitons
to cause the MuI state. Moreover, the luminescenceenergy spectrum (see Fig. 1b) and lifetime shifted
considerably from those of the intrinsic 1tluminescence indicate that the luminescence isassociated either with i) an excited state of theself-trapped exciton (STE), e.g. Gg2 s3.E+ u (or its
equivalent for off-center STE), or ii) a lowest
triplet state with modified ionic configuration forthe hole, e.g., Br32-, of the self-trapped exciton,
which are presumably caused by the muonium
formation process at its final stage.3)
The present result also indicates that themissing amplitudes of the JlSR signal in otheralkali halides at lower temperatures 2) might be
attributed to the formation of the Mu I -like state
which undergoes unobservably fast depolarization due to the paramagnetic interaction withthese STEts produced by muon radiolysis.
.. Meson Science Laboratory, University of Tokyo- 72 -

0.4--

io-MuL-

~15 ~

0.3

p..
~ 10 ~

:::J.

~

Z

.........

::l~zOo 0.2

t

20,..

~

Bdw;) iii iii Be

20 30 40 50
Temperature(K)

~

0.1

a)

<I>
<fo~

0.0 0

~

~0~<»'<>

50

D

100

~

h.

150

200

Temperature (K)
...-

J\

:::i

I ,

b)

<
'-"

-.....
~

-0
0

~

c::

0
.....
0

..c:::~

1

2

4
3
Energy (eV)5

Fig.I. (a) Temperature dependence of luminescence
yield and lifetime induced by positive muon
implantation in KBr. (b) The energy spectrum of theluminescence at 25 K. The intrinsic luminescence
spectrum is shown by a dashed curve where the peakdenoted by a or 1t is associated with the triplet or
singlet STE state.

References
1) R. Kadono, A. Matsushita, and K. Nagamine: Phys.
Rev. Lett. ,67, 3689 (1991).
2) Hp. Baumeler et al.:Hyp. Int., 32, 659 (1986).
3) R. Kadono, A. Matsushita, K. Nishiyama, and K.
Nagamine:Phys. Rev. B ,46,8586 (1992).

RIKEN Accel. Prog. Rep. 26 (1992)

111-2-15. Irradiation-Enhanced Solid Krypton Formationin Kr-Implanted Aluminum
E.Yagi
It has been demonstrated that heavy inert gas atoms(Ar, Kr and Xe) implanted into metals at ambient
temperature precipitate into a solid phase (solid inert gas
bubbles) at high implantation doses,1.2) and that they
have an epitaxial face-centered cubic (fcc) structure in fcc
matrices.
In previous studies we have investigated thenucleation and the growth of bubbles in Kr-implanted
aluminum by an ion-channeling method, and observedthat at the initial stage of implantation, various types of
Kr-vacancy (V) complexes such as KrV 4, KrV 6 andlarger ones are fonned, and they act as nucleation centerfor the subsequent bubble formation. 3)
In the present study, in order to elucidate themechanism of solid bubble formation, the effect of postimplantation irradiation by an analysis beam on the
behavior of the Kr-implanted aluminum wasinvestigated by the ion-channeling method and it wasobserved that the post-implantation irradiation enhanced
the formation of solid krypton. The Kr atoms were
implanted into an Al single crystal up to a dose of
Ix10 15 Kr/cm 2 or 6x10 15 Kr/cm 2 at room temperature.
The channeling analysis was performed for the <100>,<110> and <111> channels with a I MeV He beam.
In the as-implanted state of the Ix 1015Kr/cm2-implanted
specimen, the <100> and <111> Kr-angular profiles
exhibited a shallow dip with the same half width as thatof the AI-channeling dip, while the <110> Kr-profile
consisted of a central peak and the shallow dip with thesame half width as that of the AI-dip. After irradiation
with the analysis beam up to doses higher than
4xI0 16He/cm 2, including the irradiation dose during thechanneling analysis, a channeling dip approximately
1.5-1.8 times broader than the AI-dip became observedin <100>, <110> and <Ill> Kr-angular profiles. As
an example the result on the < 100> channel is shown in
Fig. I. This broad dip indicates the formation of solid
krypton bubbles; the post-implantation-irradiation
enhances the solid krypton formation. The broad dip
results from the channeling effect in the solid krypton
crystals. From this result, the following mechanism
was proposed,
In the as-implanted state the
IxlO I5 Kr/cm 2-implanted specimen has a large numberof cavities consisting of many Kr atoms (approximately

V(a)

0

o

u1
>=
o

UJ
N

::;

-<

'

(b)

(c)

.

\. :/,
-..;.

1.

~ 0.5

o

z

ANGLE(d~)

Fig. 1. <roo> channeling angular profiles for the
lxl0 15 Kr/cm 2 -implanted specimen, (a) in the asimplanted state, (b) after irradiation with
5.lxl0 16He/cm 2 and (c) 7.lx10 16He/cm 2 .

180 Kr atoms on average) and many vacancies.
When a large number of cavities are present they act aseffective sinks for irradiation-introduced interstitials.
The vacancies in the cavities are annihilated by theabsorbed interstitials, and, therefore, the ratio of thenumber of the Kr atoms to that of the vacancies in thecavities, i.e., the pressure of the cavities, increases. In
the cavities, in which many Kr atoms are contained andthe pressure reaches the threshold value required for solid
krypton formation, the Kr atoms precipitate into a solid
phase. This model was confinned by the observationon the 6xI0 15 Kr/cm 2-implanted specimen. These
processes occur also during Kr implantation.
The more detailed description is given in Ref. 4.
References
1)
2)
3)
4)

- 73-

A. vom Felde, J.Fink, Th. MUller-Heinzerling, J,
PflUger, B. Scheerer, G. Linker, and D. Kaletta: Phys.
Rev. Lett., 53, 922 (1984).
C. Templier, C. Janouen, J. -Po Riviere, J. Delafond,and 1. Grilhe: C. R. Acad. Sci. Paris, 299, 613 (1984).
E. Yagi, I. Hashimoto, and H. Yamaguchi: J. Nucl.
Mater., 169, 158 (1989).
E. Yagi: Phys. Rev. Lett., 67, 3804 (1991) . .

RIKEN Accel. Prog. Rep. 26 (1992)

111-2-16. Analysis of Damage in Both Eu- and Tb-Implanted CaF2
K. Aono, M. Kumagai,* M. Iwaki, and Y. Aoyagi
showed mainly three peaks, which were close to thoseof three primary colors and shifted by -430, -545 and-600 nm. In order to develop white luminescence visible to the naked eye by selecting the fIuences of Euand Tb- ions, the most suitable condition for the fluences has been investigated. TIle europium and terbium
are rare earth metals, and have similar atomic weights.

We have carried out a study of irradiation and impurity doping effects on CaF2 in the ion implantation forvarious kinds of impurities. l ) TIle luminescence spectrafrom Eu-implanted CaF2 were blue and orange. The
luminescence spectrum from Tb-implanted CaF 2 wasgreen. TIle luminescence spectra from CaF2 implantedwith both Eu- and Tb- ions (double implantation)
15000

Ca

F

." .......

Tb + Eu

!
....

300

....

....
.:....

o'.

random........ ~- ... ..
5000:........... ........

o

200

'.

,. :
~

o

' .

: ,.:

~

....... aligned!'.

......-...............~

100

.~':

$ .:':::.

.... ::...1.:~~.:....... .
0+------------------------------1.5
1.0
0.5

ENERGY (MeV)
Fig. 1. Random and <111> aligned spectra obtained for CaF implanted
2

In this study, the Eu- and Tb- implantations were
performed with f]uences of 5xl014 ions/cm 2 at 100 keY.
The < 111 > single crystal CaF2 target was in random
directions and at room temperature during ionimplantation. Rutherford backscattering spectroscopy
was employed for measuring depth profiles and latticesites of Eu and Tb atoms implanted in CaF 2' Figure 1
shows random and <111> aligned spectra for the specimens implanted with 5x1014 Tb+/cm 2 and 5x1014
Eu+/cm 2. The random spectra obtained from as-implanted CaF2 have the same shape as for unimplanted
specimens. The depth profiles of both Eu and Tb atoms
exhibit the Gaussian-type distribution. The spectra of
Eu atoms have not been separated from that of Tb
atoms. The angular scans were made for the host Ca-

and impurity ion yields around the <111> direction.
Europium and terbium have the same angler profile asCa, suggesting that most of the implanted impurity
atoms occupy substitutional lattice sites.
The implantation with 5x10 14 Tb+/cm 2 and 5x10 l4
Eu+/cm 2 is not yet a suitable condition for developing
white luminescence spectra. However we have theconfidence that from these measurements we shall beable to find out the range of fluence introducing noserious radiation damage.

References
1) K.Aono, M.lwaki, and S.Namba: Nucl. Instr. Meth., B46,

* Faculty of Engineering, Toyo University.

-74-

220 (1990).

RIKEN Accel. Prog. Rep. 26 (1992)

111-2-17. Single Event Burn-out in Power MOSFET by High-Energy Heavy Ion
S.Matsuda, S.Kuboyama, T.Tamura, M.Nakajima, M.Uesugi,
T.Kanno, J.Ohya, T.Ishii, T.Kohno, N.Inabe, T.Nakagawa,
K.Furutaka, Y.Futami, M.Kase, A.Goto, and Y.Yano
The power MOSFET has excellent performance
as a power switching device. So it is expected to be
applied to the spacecrafts. However, the power
MOSFET has a possible catastrophic failure mode
known as Single Event Burn-out (SEB) which isan important point to be considered in spaceelectronic applications. The SEB is triggered uponincidence of high-energy heavy ion when the
power MOSFET is biased with high voltage.
To study the SEB mechanism, a collectedcharge spectrum in the power MOSFET was
measured by a pulse-height analyzer system witha modified charge-sensitive amplifier which has avery wide dynamic range. From the experimental
data obtained last year with several kinds of ions ofenergy 117-200MeV, LET of lO-36MeV ·cm2/mg
in Si, and range of 20-52~m in Si, it wassuggested that the SEB occurred when the collectedcharge reached a certain value. l ) The power
MOSFET used has a 43~-thick epitaxial layer
sensitive to SEB. Since uniformly created charge
distribution in the whole epitaxial layer is necessary
to study the detailed mechanism, high-energy Xeions having a longer range from the RlKEN Ring
Cyclotron were utilized this year. Parameter of Xeions is shown in Table l.

different drain breakdown voltages. A large
collected charge is observed for a high breakdown
voltage sample with a thick epitaxial layer. Eachsample has different Q rn and spectrum. To improve
the SEB hardness of a power MOSFET, moredetailed analysis will be performed . for the
dependence of Qrn and spectrum on the device
structure, impurity profile and LET of ions.

Xe ion~(MeV/u)10

26

LET in Si(MeV ·cm2/mg)

52

36

Range in Si

(~m)

100

240

~I

Vos=lOOV

xeion.J

~

::s
0
U
(l)

Vos=90V

Ni ionv::=;

VDs=280Vc..

Ni ion10.1 Hf 101

l~1(y 10· lOS Hf

Collected Charge [pC]
Fig.I. Collected charge spectra by 3500MeV Xe and
200MeV Ni ion irradiations as a function of drain
bias voltage V DS.

Drain

AJQrn
LA II

Table 1. Parameter of Xe ions.
EnergylJ\~I

SEB
Signal~SEB
Signal~I~

Breakdown
Voltage
800V
500V

::s

0

U

Typical collected charge spectra created by Xe
ion irradiation are demonstrated in Fig.l together
with the data obtained with Ni ion irradiation. Leftpeak corresponds to the collected charge multipliedby the avalanche effect within the electric field ofa drain junction. Right peak corresponds to theinjected charge from a source junction amplified bya parasitic bipolar transistor. At a high drain bias
voltage V DS' both peaks move toward right, and
SEB is triggered when a threshold charge Qrn isreached. Since a large amount of energy isdeposited by Xe ions, SEB is triggered at evenlower V DS compared with Ni ions.
Figure 2 shows the charge spectra obtained by
Xe ion irradiation for several samples which have

250V

(l)
ell

=;

c..

120V

10-1 10°101 1Ql 10J Ht

lOS 106

Collected Charge [pC]Fig.2. Collected charge spectra by 3500MeV Xe ion
irradiation for various drain breakdown voltage
samples.

References
1) S.Kuboyama, et al.: "Mechanism for Single-Event
Burnout of power MOSFETs and Its Characterization
Technique," to be published for IEEE Trans. NucL
Sci.:(1992.Dec).

-75-

RIKEN Accel. Prog. Rep. 26 (1992)

111-2-18. Exact Calculation of the Second-Born Cross Sections

for Particle Transfer into Excited States
N. Toshima

The Thomas-double scattering mechanism has been one of the most controversial
problems in the field of atomic collisions. 1) In
the original picture of Thomas, two successive binary collisions lead to electron captureby an incident ion from a target atom. In
general three-body rearrangement collisions,

P + (Tc) ~ (Pc) + T,

(1)

three ways of Thomas mechanism are possible: (i) P hits c in the first binary collision and c makes the second collision withTj (ii) P hits c in the first collision andthe recoiled P makes the second collision
with Tj (iii) P hits T in the first collisionand the ejected T makes the second collision
with c. In some cases the critical scattering angles of the above three processes coincide and they inevitably interfere. Thoughnonperturbative treatments of the Thomasmechanism were carried out recently and theimportance of higher-order corrections wasshown,2,3) precise calculation of the secondBorn amplitudes is also needed for the investigation of the interference effect of the
double-scattering processes.
Exact calculations of the second-order
Born amplitudes for electron capture havebeen reported in several papers, but all of
the performed calculations are only for thecapture into the Is state. The contribution of capture into excited states is generally taken into account by multiplying afactor of 1.2 under the assumption that thesame scaling law of l/n 3 (n is the principal
quantum number of the final state) holds as
the high-energy behavior of the first-Born approximation. It is not evident whether thesecond-Born, especially the differential crosssections also satisfy the same scaling law.

-76 -Besides, destructive and constructive interferences, which occur only in exicited states,
can be identified only if the amplitudes arecalculated directly with high precision.
We have calculated the second-Borndifferential cross sections for exotic-atomformation into the excited states rigorously without a recourse to any further
approximation. 4 ) The processes can be classified into three types according to the mass
ratio of the three-particles. In the collisionof P + (PIL-), the Thomas mechanism takes
place only via single path (i) as in the protonhydrogen collision, while, in the collision ofe+ + H, it can proceed via two paths thatinterfere destructively or constructively depending on the parity of the final boundstates. In the third type, in which all thethree particles have an equal mass as inpositron-positronium collisions, the criticalangle occurs at 180 0 only and the two secondorder terms which are forbidden in classical mechanics are contributing significantly
to the back-scattering. Although no experimental data is available for the comparison
at present, the author hopes that this study
may help to plan new experimental research.
References
1) R. Shakeshaft and L. Spruch: Rev. Mod.
Phys., 51, 369 (1979).
2) N. Toshima and J. Eichler: Phys. Rev.
Lett., 66, 1050 (1991)j Phys. Rev. A46,
2564 (1992).
3) N. Toshima: Phys. Rev., A42, 5739
(1990); ibid., A45, 2663 (1992)
4) A. Igarashi and N. Toshima: Phys.
Rev., A46, 1159 (1992)jA. Igarashi, N.
Toshima, and T. Ishihara: Phys. Rev.,
A46~ 5525 (1992).
t

RIKEN Accel. Prog. Rep. 26 (1992)

111-2-19. Quantum Mechanical Calculation of
Slow Ion-Atom Collisions
H. Fukuda and T. Ishihara*
The molecular orbital expansion has been astandard theoretical method for slow ion-atomcollisions. The total wave function in this expansion does not satisfy the asymptotic boundary
conditions because of the use of the internuclear
coordinates to describe the relative motion ofprojectile and target . As a result, the coupledequations for the relative motion may containspurious long-range coupling terms. The difficulty of spurious couplings does not occur if thecorrect relative coordinates are used instead ofinternuclear coordinates. Such an approach has
been proposed by Kobayashi et al. 1)
The total wave function W is expanded interms of adiabatic basis functions defined by fixing the relative coordinates ROt of each arrangement channel a in the form

10 1.........
N
c.o

I

==

10°
10-1

U

0

.-

"-"

c:

0

+-'

10 -2
10-3
10-4

u

Q.)
CI':)

10-5

CI)
CI)

6
.... 10u
10- 7
0- - Present resu Its------ Sem i -c Iass i ca ,3)• Ref. 4

10-8
10 1
10 2
10 3
Center of Mass Incident Energy (eV)Fig. 1. Charge transfer cross sections for
H(lS)+4He 2 + .

(1)
H(lS) + 4He 2 + ~ H+ + 4He+(n = 2)
Radial function XOtv(R Ot ) satisfies a set of coupled integro-differential equations,
2dd XOtv "'[- dR2 + L.J UOtV,Otv l + 2POtV,OtVI dR ]XOtV'
Ot
v'
Ot

+L
Vi

J

dTOt VOtV ,{3v' X{3v,(R{3) = O.

(2)

We have developed an iterative method 2 } tosolve Eq. (2) by expanding the radial functionin the power of the ratio of the relative velocity
to the electron orbital velocity,(4)

for the incident energy Ei = 20-200 eV in thecenter of mass system are shown. A solid curveis the result of the present calculation and adashed curve is the semiclassical limit of thepresent calculations. 3 ) The two curves indicatethat they would merge into each other at a slightly
higher energy. Solid squares in Fig. 1 are the results of the quantum mechanical calculation of
Hemert et alp 4)References
1) K. Kobayashi, T. Ishihara, and N. Toshima:
Muon Catalyzed Fusion.2, 191 (1988).

where tl.{3Ot = R{3 (TOt , ROt) - ROt. Since we areinterested in slow collisions, the first a few terms
are retained in Eq. (3).
In Fig. 1, as a numerical example, cross sections for the charge transfer process* Institute of Applied Physics, University of Tsukuba.
-77-2) H. Fukuda and T. Ishihara: Phys. Rev., A46,
5531 (1992).
3) T. G. Winter and G. J. Hatton: Phys. Rev.,
A21, 793 (1980).
,:
4) M. C. Hemert et al.: Phys. Rev., A31, 2227
(1985).

RIKEN Accel. Prog. Rep. 26 (1992)

111-2-20. Double Ionization of He by High-Energy
Photon Impact
K. HinoDouble photoionization (" 2e) of He is
one of the simplest atomic processes forthe three-body Coulomb problem. The
electron-electron interaction plays a decisive role in the simultaneous ionization of
two electrons. According to the resu1t.s of
calculations using the many-body perturbation theory (MBPT),1) the final state correlation (FSC) has a significant contribution
as does the ground state correlation (GSC)
even at high photon-energy E-y. The purpose of the present article is to evaluate
the ratio, R-y = a++ / a+, of the double- tothe single- photoionization cross sections of
He in a high photon-energy region by useof quite accurately correlated initial and final state wave functions within the nonrelativistic framework, and to compare theresults with the very recent observations using synchrotron radiation by Levin et al. 2 )In the present calculations, attention islllainly focused on the effect of the FSC
on (,,2e). The ground state wave function of He is provided by the configurationinteraction method and its energy is equal
to -2.90276 atomic unit, differing from theexact value by 0.001 atomic unit. The fi~
nal state is expressed by the analytic wave
function, consisting of a product of three
confluent hyper geometric functions. 3 ) This
wave function satisfies the proper asymptotic Coulomb boundary condition of thethree-body break-up channel,4,5) and incorporates the electron-electron interaction ina non-perturbative wa.y.
Figure 1 provides the present result of R-yfor (,,2e) of He at E-y=1.0-12.0 keY. For
comparison, the result without incorporating FSC, hereafter referred to as R;O) , isalso depicted. This essentially corresponds
to the evaluation by Byron and loachain. 6 )The ratio R-y is mostly in agreement withthe experiments in the keY-region of E-y.2)
However, R-y is much discriminated from
R;O) even at very high E-y. This result reveals the evidence of the ilnportant role of
the FSC on (" 2e).

o

4 o

- - : Present- - _. : Without FSCo: Carlson (1967)• : Levinetal (1991)• : Levin et a1 (1992)
c : Samson et at (1992)o

1

Photon Energy (keV)

Fig.I. Ratios of the double- to the single- photoionization cross sections versus photon energy. Experimental data are taken from Refs. 2, 7 and 8.

References
1) T.lshihara et al.: PhY3. Rev., A44, R6980(1991 ).
2) J.C.Levin ~t al.: Phys. Rev. Lett., 67, 968(1991) and private communications (1992).
3) C.Garibotti and J.E.Miraglia: Phys. Rev., A21,572 (1980).
4) P.L.Altick: Phys. Rev., A21, 1381 (1980); ibid.
A25, 128 (1982); J. Phys., B16, 3543 (1983).
5) R.Peterkop: J. Phys., B15, 1751 (1982).
6) F.W.Byron and C.J.Joachain: Phys. Rev.,
164, 1 (1967).
7) T.A.Carlson: Phys. Rev., 156, 142 (1967).
8) J.A.Sarnson et al.: Phys. Rev., 7277 (1992).

-78-

RUffiN Accel. Prog. Rep. 26 (1992)

111-2-21. Double Excitation of H- by Fast Protonand Anti-Proton Impact
K. Hino, M. Nagase,· H. Okamoto,· ~1. Matsuzawa, a.nd M. Kimura··

Is2 1 se, 2s2 1 se and 2p2 1 De, the shaperesonance state 2s2p ' 1 po, and the lowlying singly ionized state Is kp 1 po. The
2s2p 1 po and Is kp 1 po states are made discrete into 10 energy-meshes for the present
calculation. Tabel 1 indicat.es our calculated results ba.sed on the close-coupling
method (CC), the first-order plane-wa.ve
Born approxilnation (PWB 1), and the firstand the second-order distorted-wave Born
approxilnat.ion (DWBI and D\VB2) at theenergies of 0.1 and 1.5 MeV lu, respectively.

Recent advance of experimental technique has made it possible to reveal evidences of electron correlation effects in thecourse of ion-atom collisions. 1- 3 ) In this article, we evaluate cross sections of double
excitation of H- induced by p and p ilnpact
in the MeV lu-energy region. Wave functions of H- are generated using the hyperspherical coordinate method.
To calculate the excitation cross sectionsof H-, a set of 67 states is employed as basis
functions to analyze the collision dynamics.
The set consists of the discrete states

Table 1. Calculated cross sections (in the unit of 10- 20 cm2 )for double excitation process of H- at impact energy of(a) 1.5 MeVlu and (b) 0.1 MeV/u, respectively.
(a) 1.5 MeV lu

PWB1
DWB1
DWB2
CC

(b) 0.1 MeV lu

PWB1
CC

2"~ I

proton
9.43
9.35
9.40
9.62

se

2p~ I Deanti-proton
9.43
9.41
9.31
9.49

proton
0.458
0.456
1.29
1.26

2,, 21 se
proton anti-proton
141
141
118
124

proton6.85
24.4

References
1) P.W.Arcuni and D.Schneider: Phy". Rev., A36,
3059 (1987).

-Department of Applied Physics and Chemistry,
University of Electro-Communications.
_. Argonne National Laboratory and Department of
Physics, Rice University.

-79-

anti-proton
0.458
0.458
1.57
1.43

2p2 I Deanti-proton
6.85
79.5

2) J.O.P.Pedersen and P.Hvelplund: Phy". Rev.
Lett., 62, 2373 (1989).
3) J.P.Giese et at.: Phy". Rev., A42, 1231 (1990).

RIKEN Accel. Prog. Rep. 26 (1992)

111-2-22. Inner-Shell Vacancy Production of Fast Ar Ionsin Collision with Various Target Elements
Y. Naitoh,* Y. Zou, T. Kambara, Y. Awaya, and K. Fujima
Experimental observations have shown that theintensity of KQ'-hypersatellites of projectile Ar ionsoscillates against the target atomic number Zt, when
the projectile Ar ions are ionized at collision energy between 30 and 100 MeV.!) Since direct excitation cross sections by a fast charged particles show
monotonous dependence on Zt, the shell structure of
the target and projectile makes this observed oscillation, in other word, the binding energy matchingrather than momentum plays an important role.
Figure 1 shows Is to 2p excitation cross sectionsof Ar ions in collisions with various targets calculated by a simple Born approximation. Note thatthe Born cross section depends only on the effecti ve
charge of the target and the velocity of the ions. As
is expected, there is no sign of oscillation which isclearly seen in the experiments.
Now we turn to the Fano-Lichten excitation modelin which energy crossing of the target and projectileions stimulates the inner shell vacancy production.
The theoretical estimation based on this idea needs
a rather complicated procedure. First we have to calculate the correlation diagrams of the system. Figure
2 shows the correlation diagrams of Ni-Ar and Cr-Ar
systems using the DV-XQ' method. In the Cr-Ar system, the Ar Is state matches with the Ar 2p state at
the united ak).m limit. However, Ni 2p correlates to

(b)

«(1)

Interatomic Distance(au)Fig. 2. Calculated molecular-orbital potential energyfor (a) Ar+Cr and (b) Ar+Ni.

30,r - - - - - - - - - - - - - - - - - - ,

Cr-Ar
."

o

0.1£+01N.

e ,Fig. 3. Total cross section of Ar IsO" to Ar 2p7r excitation
as a function of the collision energy.

0.5£+00coI

0.2£+00

Ar Is in the Ni-Ar system. The inner-shell excitation
cross sections shown In Fig. 3 are calculated by integrating so called a close coupling equation with fivestates. The cross section for Ni-Ar is smooth against
collision energy. On the contrary, the Cr-Ar systemshows oscillation and exhibits a valley at collision energy of about 0.15 x 10 7 a.u. (Center of mass). This isthought to be a reason for KQ'hypersatellite intensity
oscillation observed experimentally.

oO.IE+OO

O.SE-Ol><

0.2E-Ol

O.IE-OI

O. 5E-02 L..--_..I...-_..L.-_ _L..--_.l--_.J......._ _L..------J

2

5

10

20

50

References

Incide,nt Energy (MeV)

Fig. 1. Cross section of Is to 2p excitation of Ar calculated by a Born approximation.

*Fac. Eng., Yamanashi Univ.

-80-1) Y. Zou, T. Kambara, Y. Kanai, Y. Awaya, K. Ando,
M. Ohura, A. Hitachi, and S. Kravis: Riken Aced.
Prog. Rep., 25, 69 (1991).

RIKEN Accel. Prog. Rep. 26 (1992)

111-2-23. Resonant States of Two Electron Atomic Systems
H. Sato and S. Hara

In this research, the projection operator
formalism is applied to obtain the energies forthe resonant (autoionising) states of two electron
atomic systems.
The Hamiltonian H of the system is given by

where z is the nuclear charge, ri the distance of ith electron from the nucleus and r12 that between
two electrons. The total wave function 'I'(rl,r2)
and the energy EO of the autoionising state are
given, in the first approximation, by the solutionof the eigen value equation

function <l>i is given by<l>i(rl,r2)

where f(r) is the Sturmian functions. The
coefficients ai are determined by a variational
procedure.
We have constructed a general computer code to
calculate the resonant energies and the wave
functions for the two electron atomic systems. The
results for He atom are given in Table 1 as an
example. 'Table 1. Resonant energies for He autoionisingstates in atomic units.
where Q is the projection operator introduced by
Feshbach,l)15(2s2)3p (2p 2)
3p(2s2p)ID(2p 2).lp(2s2p)
IS(2p 2)

where
PI = cl>O(l»<cI>o(1),and cl>o(1) is the ground state wave function for the
one electron system. The total wave function'I'(rl, r2) is expanded aspresent

Ref. .2)

Ref. 3)-0.77872705-0.76145106-0.71041379-0.70248016-0.69251193-0.62164874-0.7787-0.760497-0.7781585-0.69313-0.621927-0.6917983-0.6205051

References
1) H. Feshbach: Ann. Phys., N. Y., 19, 287 (1962).

2) Y. K. Ho: Phys. Rep., 99, 1 (1983).
3) B. H. Bransden and C. Joachain: "Physics of Atoms

and Molecules", Longman, London and New YorkIn the above expression, the configuration-81-(1983).

3. Radiochemistry and Nuclear Chemistry

RIKEN Accel. Prog. Rep. 26 (1992)

111-3-1. Preparation of Radioactive Multitracer Solutions from a
High-Energy Heavy-Ion Irradiated Au Target by Meansof a Supported Liquid Membrane (I) ts. Ambe, Y. Ohkubo, Y. Kobayashi, M. Iwamoto, M. Yanokura, and F. Ambe
A large number of radioactive nuclides useful as
tracers are produced in targets by high-energy heavy-ion
irradiations by the RIKEN Ring Cyclotron.t,l) With
the aim of developing automated methods of preparing
multi tracer solutions, we are investigating separation ofradioactive nuclides by means of supported liquid
membranes. Separation by supported liquid membranes
is considered to be especially suitable for preparation ofmultitracer solutions because of (i) simplicity ofoperation leading to facile automation, (ii) feasibility ofconcentrating tracers into a small volume of a solution,and (iii) necessity of a far smaller amount of extractants
than conventional solvent extraction. This paper
describes successful removal of the target material Au
from multitracers by means of a TBP-decalin membrane.
The irradiated Au disk was dissolved in 10 em3 of aquaregia A portion of the solution was evaporated todryness. The residue was dissolved in 1 mol dm- 3
HN03 . The solution containing about 170 mg of Au3 +ions was used as a feed solution. A supported liquid
membrane was prepared by impregnating a microporous
polytetrafluoroethylene sheet with a 0.8 mol dm-3 TBPdecalin solution. Distilled water was used as strip
solutions.
The supported liquid membrane was fixed at thebottom of a Teflon vessel with a Teflon ring. The feedsolution in the outer vessel was stirred at 1000 rpm
with a magnetic stirrer. The strip solution was
circulated at the rate of 3 cm3 min-t, a given portion of
the circulating solution being trapped in a Teflon vessel
put on a pure-Ge detector for measurement of y-rays.
Measurement of 1200 s duration for the strip solution
was automatically repeated and the y-ray spectra
obtained were recorded on a disk. The strip solution was
replaced by fresh distilled water after 300 and 1300 min
in each experimental run.
Figure 1 shows the transport of Au3 + ions, monitoredby the y-rays of radioacti ve Au nuclides, from the 1 mol
dm- 3 HNOJ feed solution. Transport of Au3+ ionsstarted immediately after the contact of the feed and strip
solutions with the membrane from each side. The
amount of transported Au3 + ions increased almost
linearly up to 55 %, where the increase tended tosaturate. By replacing the strip solution with fresh
distilled water, the transport of Au3+ ions was recovered.
After permeation overnight the strip solution was
replaced with fresh water again and conc .HN03 (2volume % of feed solution) was added to the feedsolution in order to compensate the loss of HN0 3 into
the strip solutions. The transport of Au3 + ionscompleted in less than 2000 min from the beginning.
Radioactive nuclides of the elements, Sc, Fe, Co, Rb,
Sr, Y, Zr, Nb, Rh, Ag, Te, Ba, Ce, Eu, Gd, Yb, Lu,ill, Ir, and Pt were found remaining in the feed solution
after the permeation of those of Au. In the strip
solutions. 20 % of total Ag+ ions were observed and thetransport of the other elements was less than 5 %.
It is concluded from the observations described abovethat the supported liquid membrane of TBP-decalin is
effective for separating multitracers from an Au target
irradiated with high-energy heavy ions. Essentially all
the radioactive nuclides remain in the 1 mol dm-3 HN03
feed solution, though removal of Au takes somewhat
long time. The time required for eliminating Au is
expected to be considerably shortened by supplying fresh
distilled water continuously as the strip solution andalso keeping the HN03 concentration of the feedsolution close to 1 mol dm- 3 by automaticallycontrolled addition of HN03.

-<
0~

100
80

0
0
0

~

~

0

~

60

0

40

en
c:
cu

20

a.
~

t-

O

0

I
500

1000

1500

2000

Time (min)Fig. 1. Transport of Au3 + ions from a 1 mol dm- 3 HN03
feed solution. The two vertical lines in the frame
indicate the time of replacement of the strip sol ution
with fresh distilled water.

References
1) S. Ambe, S. Y. Chen, Y.Ohkubo, Y. Kobayashi, M.
Iwamoto, M. Yanokura, and F. Ambe: Chem. Letl.,
1991, 149.
2) S. Ambe, S. Y. Chen, Y. Ohkubo, Y. Kobayashi. M.
Iwamoto, M. Yanokura, and F. Ambe: Anal. Sci., 7,

t Condensed from the article in Appl. Radial. Isot.43,

1533 (1992).

-83-

Suppl. 317 (1992).

RIKEN Accel. Prog. Rep. 26 (1992)

111-3-2. Preparation of Radioactive Multitracer Solutions from a

High-Energy Heavy-Ion Irradiated Au Target by Meansof a Supported Liquid Membrane (11)t
S. Ambe, Y. Ohkubo, Y. Kobayashi, M. Iwamoto, M. Yanokura, and F. Ambe
This paper describes successful removal of the target
material Au from multitracers in 8 mol dm- 3 HCI bymeans of a TBP-decalin membrane supported on a
microporous polytetrafluoroethylene sheet. TBP was
adopted since Au3 + has the largest distribution
coefficient of all the elements reported in extraction
from 1-12 mol dm-3 HCI.
The irradiated Au disk was dissolved in 10 em3 of aquaregia. A portion of the solution was evaporated todryness. The residue was dissolved in 8 mol dm-3 HCI.
The solutions containing about 170 mg of Au3+ ionswere used as a feed solution in each separation. The
other experimental conditions are similar to the previous
report. 1)
The result on the 8 mol dm-3 HCI feed solution isshown in Fig.!. Transport of Au3 + ions proceededmuch faster than in the case of the 1 mol dm- 3 HN03
solution, attaining 93 % in 300 min by the first strip
solution. In the second and third, 6 % and 1 % of total
Au ions were found, respectively. No y-rays due to Au
nuclides were found in the feed solution, indicatingcomplete transport of Au3 + into the three strip
solutions.

-«
0~

0

t:
0
c.
U)

100 . . . . - - - - - - -8M Hel feed soln.
.3rd H20 strip soln.
~ 2nd H20 strip soln.
01st H20 strip soln.

cf.80
15
Q)
1:

060
0.
(II

c:

ca

t,40
:J

<

20

o
ScFeCoRbSr Y

ZrNbRhAgTee.CeEuGdYbluHf Ir PtAu

Fig. 2. Transport of various elements from an 8 mol dm- 3
HCl feed solution.

100
80

0

60

0

40

0
0
0

:::J

"I-

radioactive nuclides of Co, Rb, Sr, Y. Rh, Ag, Ba, Ce,
Eu, Gd, Yb, and Lu, and about half of those of Hf, Ir,
and Pt. On the other hand, more than 80 % of Sc andZr, and essentially all of Fe, Nb, and Te nuclides weretransported into the strip solutions together with Au.
The stripping behavior of the elements is well correlatedwith their distribution coefficients in TBP-HCI solvent
extraction.

c...I-as 20

0
0

500

1000

1500

2000

Time (min)Fig. 1. Transport of Au3 + ions from an 8 mol dm-3 HCI
feed solution. The two vertical lines in the frame
indicate the time of replacement of the strip sol ution
with fresh distilled water.

In the case of 8 mol dm-3 HCI feed solution, however,elements other than Au were observed to be transported
more or less to the strip solutions as shown in Fig. 2.
In the feed solution remained more than 60 % of the

It is concluded from the observations described abovethat the supported liquid membrane of TBP-decalin is
effective for separating multitracers from an Au target
irradiated with high-energy heavy ions. The 8 mol dm-3
HCI feed solution is recommended for certain elements
because of the quicker separation of Au. Choice of afeed solution also depends on the experiment in which
the multi tracer solution is used.
A series of experiments are now under way toestablish efficient procedures for preparing multitracer
solutions from different kinds of targets irradiated byhigh-energy heavy ions. A search will be made forliquid membranes, leaving a target element in the feedsolution and letting all tracers permeate the strip
solution. Combination of two or more liquid
membranes is expected to yield groups of tracers usefulfor different specific purposes.
References
1) S. Ambe, Y.Ohkubo, Y. Kobayashi, M. Iwamoto, M.
Yanokura, and F. Ambe: This report, p. 83.

t Condensed from the article in Appl. Radiat. Isot.43,

1533 (1992).

-84-

RIKEN Accel. Prog. Rep. 26 (1992)

111-3-3. Separation of Multitracer from Heavy-Ion IrradiatedTargets by Heating under Reduced Pressure
M. Iwamoto, S. Ambe, Y. Ohkubo, Y. Kobayashi, M. Yanokura,
H. Maeda, and F. Ambe

Rotating
We continued in this period a series ofApparatus
experiments on the separation of multitracers
from targets irradiated with heavy ions from the
Mantle heater
RIKEN Ring Cyclotron by heating under
reduced pressure. 1.2)
The apparatus was improved in several points
resulting in high yields of tracers. The cold
finger used in previous experiments2) was no
more used, because the radioactive nuclides
Hel Solution
evaporating from the molten target were foundto be efficiently collected on a part of the innerwall of the quartz tube. They formed a bandhaving a width of a few cm just at the exit ofFig. l.The apparatus for dissolving radioactive nuclides.
thefumace.
Since the cold finger was abandoned, thesizes of both the quartz tube and the electric
furnace were made smaller. The volume ofobtained. The percentage of recovery on
washing solution was consequently made muchaverage was 70-80% of the radioactive
smaller than before.
nuclides deposited on the inner wall of theAfter heating a target under reduced pressure
quartz tube. Detailed yields for each nuclideof a few Pa, the quartz tube was drawn out ofwill be re}X>rted elsewhere.
the furnace and the target was remov~. Then
5 cm3 of 6 mol/dm3 HCI was poured into thequartz tube. The tube was set on an apparatus , References
1) M. Iwamoto et al.: RIKEN Accel. Prog.
being inclined enough so that the inside wall of
the tube got wet with the acid solution (Fig. 1).
Rep.,2S, 96 (1991).
The quartz tube was rotated slowly by means of2) M. Iwamoto et al.: Anal. Sci., 7, Suppl.
a motor for more than 1 hour. Thus, a 6
313 (1991).
3
mol/dm HCI solution of multitracers was-85-

RIKEN Accel. Prog . Rep. 26 (1992)

111-3-4. Application of the Radioactive Multitracer Technique toa Study of Adsorption of Metal Ions on a-Fe203 t
S. Ambe, S. Y. Chen, * Y. Ohkubo, Y. Kobayashi, M. Iwamoto, and F. Ambe
We established convenient and reliable radiochemical
procedures by which radioactive multitracer solutions
free from carriers are prepared from Au, Ag, and Cu
targets irradiated with a high-energy heavy-ion beam
accelerated by the RIKEN Ring Cyclotron. 1,2) Use of
the multitracer solutions enables us to determine thecharacteristic behavior of different elements understrictly identical experimental conditions and to make aprecise comparison among them.
Here, the multitracer technique was applied to thestudy of the adsorption of elements on a modelcompound, a-F~03, from aqueous solutions. The pH
dependence of the adsorption of the elements, Sc, Ga,
As(V), Se(lV), Rb, Sr, Y, Zr, Nb, and Mo(VI), wassimultaneously determined using a multitracer solution
separated from an Ag target irradiated by a 135
MeV/nucleon IlC beam.
a-Fe203 was added to the multitracer solution at pH
2. The pH of the resulting suspension was adjusted todifferent values with a dilute NaOH solution. The
suspension was shaken at room temperature for 1 h.
After centrifugation of the suspension, the supernatantsolution was withdrawn for measurement of y-ray

aspects of adsorption. Similar work on different
adsorbates is also in progress.
100 r - - - - -_ _ _. . . .. . ,100 , - - _ . .
.....~._.--....,
_

80

80

~

~60

I

.2

~ 60

Sc

e.4O
~ 20

•

~ 20

'I

o. . . . . . . . .

..IIL-.<.
. _ " - -.............-'--.....J100 r - - - - - i I I I_ _ _ _____
~

80

~60

100

•

•• •

....---_.-=-__• ____------,

80

~ 60

As(V)

•
Se{1V)

1

14O

40

~2O

~2O

•
•
•

.

o'--"'--"""-,"""__,_-,--"",,,--.....J
100 ,--_ _ _ _ _---,

100r--------,

eo

80

~0 60

1

40

'0

I

<20

o............
--~-~.-......"'i.t'-.--..Jo...................................~

spectra.

100 r - - - - - - " . . : - -........

Figure 1 shows the pH dependence of adsorption of 10
elements obtained simultaneously in an experimental
run. The patterns of adsorption can be classified into
the following five groups: A) Sc, Y, and Zr, whose
percentage of adsorption increases with increase of pH,
attaining complete adsorption in the alkaline region, B)
Se(lV) and Mo(VI), which are adsorbed almost
completely in the acid pH range, but whose adsorption
decreases with increase in pH, C) Ga, which is adsorbed
completely in the neutral region, but whose adsorption
decreases in both acid and alkaline pH ranges, D) Rb andSr, which show little or low adsorption within theentire pH range studied, and E) As(V) and Nb, whichgive high adsorption yield within the entire pH range.
The results described above demonstrate the usefulnessof the multitracer teChnique in studying the behavior ofa number of elements under identical experimental
conditions. The adsorption characteristics of theelements revealed in the present work provide a basis forunderstanding their behavior in natural environments.
Detailed discussion on the mechanisms of theadsorption in terms of the surface charge of a-Fep3 andchemical species of the elements in the multitracer
solution will be described elsewhere, along withexperimental data on other elements and those on kinetic

•

~
g 40

..

Ga

~

80

~60

••y

~60

140

140

20

<20

'0
c(

'0

•
•

O................._ - ' -........--a...~o '---"'--~_'__'"""__'_"""'--.....J100 r--~____4IiI_ _-ed...,100 r -. .~_~__- - . ,

eo

80

~60

i

,

100r--_-.::::--......,• 80... --- ... Nb~60

Mo(VI)"e- 40

40

Jo

~20

20

oL--"'-~--'-.........--a...----'o 2 " 6 8 10 12
pH

L....-__________........--a...--..J

o

2

"

6

pH

8

10 12

Fig. 1. The pH dependence of adsorption of the elements,
Sc, Ga. As. Set Rb. Sr. Y. Zr. Zb. and Mo.

References
1) S. Ambe, S. Y. Chen. Y.Ohkubo. Y. Kobayashi, M.

Iwamoto. M. Yanokura. and F. Ambe: Chem. Lett.•
1991. 149.
2) S. Ambe. S. Y. Chen. Y.Ohkubo. Y. Kobayashi. M.
Iwamoto. M. Yanokura, and F. Ambe: Anal. Sci. 7.
Suppl. 317 (1992).

It I Condensed from the article in Chem. Lett.. 6,1059(1992).

* South China Sea Institute of Oceanology.

-86-

RIKEN Accel. Prog. Rep. 26 (1992)

111 .. 3.. 5. Radiochemical Study of Adsorption Behavior of Various Elements
in Hydrochloric Acid Solutions on Activated Carbon Fiber and
Non-ionic Macro-reticular Copolymer Using Multitracer
S. Shibata, K. Watari,* Y. Noda,* S. Ambe, Y. Ohkubo, M. Iwamoto,
Y. Kobayashi, M. Yanokura, H. Maeda, and F. Ambe
Activated carbon and non-ionic macroreticular (MR.) copolymers have been reported
to be effective adsorbents for a number oforganic materials in aqueous solutions, but notenough attention has been paid on theadsorption of inorganic substances. Thosematerials have particulary high distribution
ratios (Kd) for tetrachloro complex anions ofFe(III), Ga(III) and Au(III) in above 6 mol·dm- 3 HCI solutions without any other organic
ligands. 1,2) Such peculiar adsorption behavior
has been observed with cation exchange
resins. 3 ) In the present work, the adsorption
behavior of inorganic elements in 0.01 - 10
mol·dm-3 HCI solutions of multitracer preparedfrom Ag foils irradiated with 135 MeV Inucleon
12C 4) on a novoloid-based activated carbon
fiber, Kynol ACF-1605-15, and a non-ionic
MR copolymer, Amberlite XAD-7, wasstudied.
The retention of the elements was studied
under static conditions (batch method). The
multitracer solutions were shaken with the
Sc
v
t.t1

@

[5]

adsorbents for 2 h. Aliquots of a half volumeof the supernatant were separated at the end of
sorption time. The radioactivity of the phases
was measured with a high-resolution y-ray
spectrometer, and was analyzed with the BOB
code 5) on a SUN workstation.
The distribution of the elements wasdetermined by counting the radioacti vi ty of boththe aqueous aliquot and the remaining sorbent
fraction. The distribution ratio was calculatedfromAr - As ) I 2As . V1m,
Kd
where As and Ar are the peak areas of theaqueous aliquot and the remaining portion,
respecively, and Vim denotes the volume toweight rario in cm3 . g-l.
Figure 1 shows the adsorption profiles of 18
elements in log-log plottings of Kd against theconcentration of HCl. An important feature ofthese profiles compared to those in the HN03
solution system is that increasing concentrationof HCI above 5 mol·dm- 3 tends to increase Kd
in several elements.

=(

wf.J§§EJ

Ga

As

Se

-.---. . --".. - . -.,.-, .-..... ....... ...-....
-.. --....... ... '.. '.- ' G··bJb]~§[jD,...-....
_

Rb

....,

."..

Sr

y

ZI

.,

'

-.:

NJ

Mo

Te

Au

--:ACF
Fig. 1.

..

'.

Rh

Pd

-- - -: XAO-7.

Ag-2 -1 0 1

log [Ha]

Adsorption of the inorganic multitracer prepared from Ag foils on ACF-1605-15 and XAD-7
from aqueous solutions as a function of the concentration of HCI.

References
1) K. Watari, K. !mai, S. Shibata, and M. Mima: J.
At. Energy Soc., Japan. 26,384 (1984).
2) S. Shibata, K. Watari, and K. Kaneko:
Radioisotopes, 39, 226 (1990).
3) F. Nelson, T. Murase, and K. A. Kraus: J.
Chromatog., 13, 503 (1964).

4) S. Ambe. S. Y. Chen, Y. Ohkubo. Y. Kobayashi,
M. Iwamoto, M. Yanokura, and F. Ambe: Anal.
Sci., 7, Suppl.. 317 (1991).
5) H. Baba, H. Okashita. S.. Baba. T. Suzuki, H.
Umezawa, and H. Natsume: J. Nucl. Sci. Technol.,8, 1227 (1972).

* National Institute of Radiological Sciences.
-87-

RIKEN Accel. Prog . Rep. 26 (1992)

111-3-6. Utilization of Multitracer Solutions for Studies on the Ion
Exchange Behavior of a Strongly Acidic Resin NAFION
T. Bamba, H. Harakawa, Y. Saito, K. Kimura, T. Yaita, S. Shibata, S. Ambe, Y. Ohkubo,
M. Iwamoto, Y. Kobayashi, M. Yanokura, H. Maeda, and F. Ambe

Radioactive multitracer solutions. in a canier- andsalt-free condition. prepared from silverl ,2) and gold2-4)
foils irradiated with 135 MeV/nucleon 12C ions wereused for the titled studies in a NAHON-HCI04 systemafter converting to a perchloric acid solution. The
NAHON-S01 resin. manufactured by DuPont. is a
perfluorinated polymer containing,..,5 mmol g-I sulfonicacid group as shown below. Because of the strong
acidity of the resin. a comparison of its exchange
behavior with that of a common cation exchange resin
attracts much attention.

80% of the equilibrium was attained by the 16 hours
shaking. As shown in Fig. 1, the slopes for alkali andalkaline earth metal ions in the log -log plottings wereapproximately -1 and -2, respectively, that is
cbaracteri.~c of the ion exchange. D's for noble metals
remained ratber constant with increasing acidities and5-10 times higher than those in a NAF IONhydrochloric acid system. 5)

100o

The resin. commercially available as a cylindricalshape of ca. 1mmq, x 1-3 mm, was crushed with astamp mill at liquid nitrogen temperature, ~edthrough a 50-mesh sa-een, and used. Into a small
polyethylene bottle, O.lml of the multitcacer solution
and 2.4g of the resin were introduced, and the acidity ofthe system was adju~d to 0.10 , 1.1, and 5.6mol dm-3
with percbloric acid by making the volume of thesolution to 10ml. The contents of the boule wereshaken vigorously at 25·C with an 8-sbape mode
shaker. Time of the shaking was 16 hours for the silvermultitcacer and 75 hours for the gold-multitracer. After
filtration. l' -ray spectcameuy was carried out for bothl' -ray spectra were analyzed on aphases. The
FACOM M780 computer.
The distribution ratios (D) of Na, Sc, V. Co, Ga, Rb,
Sr, Y, a, Nb, Ru, Rb, and Pd were obtained from thesilver-multitcacer runs and those of Sc, Rb,Y, a, Ag,
Ba, Eu, Gd, Tb, Tm, Vb, Lu, and Pt from the goldmultitracerruns. The D's for Sc, Rb, Y. and a obtained
from the silver and the gold runs showed that more than

-88 -

10

0.1
0.1

1

3

10

HCIO (mol dm- )4,

Fig. 1. Relationship between the D and the acidity.

References
1) S. Ambe, S.Y. Chen, Y. Ohkubo. Y. Kobayashi, M.
Iwamoto, M. Yanokura, and F. Ambe: RIKEN Aceel.
Prog. Rep., 25. 95(1991).
2) s. Ambe, S.Y. Chen, Y. Ohkubo, Y. Kobayashi, M.
Iwamoto. M. Yanokura, and F. Ambe: Anal. Sci., 7,
Suppl.,317(1991).

3) S. Ambe, S.Y. Chen. Y. Ohkubo. Y. Kobayashi, M.
Iwamoto. and F. Ambe: RIKEN Accel. Prog. Rep., 24,
73(1990).

4) S. Ambe, S.Y. Chen. Y. Ohkubo. Y. Kobayashi, M.
Iwamoto, M. Yanokura, and F. Ambe: Chem. Len.,
1991, 149.
5) J. Kawarada, T. Yaita, Y. Saito, K Kimura, S. Ambe,
S.Y. Chen, Y. Ohkubo. M. Iwamoto. Y. Kobayashi, and
F. Ambe: RIKEN Accel. Prog. Rep., 25, 98(1991).

RIKEN Accel. Prog. Rep. 26 (1992)

111-3-7. Multitracer Study on Complex Formation of Humic Acid
Y. Minai, Y. Takahashi, M. K. Kubo, S. Toyoda,* M. Ishibashi,*S. Ambe, Y. Kobayashi, Y. Ohkubo, M. Iwamoto, M. Yanokura, H. Maeda,
S. Shibata, N. Takematsu, F. Ambe, and T. Tominaga
Humic acid is a naturally-occurring organicpolyacids which can combine with various
metal cations in natural and artificially-modified
environments. Estimated stabilities of themetal-humic acid complexes were strong
enough to influence the behavior of several
elements in the environments. For instance,large values of complex formation constants ofactinide(III)-humates have been reported inrecent studies, indicating considerable amountsof actinide(III)-humates can be formed inaqueous environments. I) However, reliablestability constants were not obtained for mostof the elements which are important inenvironmental chemistry and geochemistry.
In this study the multi tracer technique was
employed to evaluate stabilities of humatecomplexes of various metal cations including
several geochemically important elements (e.g.,lanthanides). Besides, it was intended toelucidate the dependence of the stabilities onionic radius and charge which have been
believed to affect the stability of the complexes.
Multitracer solutions (3M HCI) were obtained
from the targets (silver and gold foils) irradiatedwith a I2C beam accelerated in RIKEN Ring
Cyclotron. The procedures for separation of
the multitracer from the targets were given
elsewhere. 2,3)
After evaporation of themultitracer solutions containing hydrochloric
acid, O.OOlM perchloric acid was added toyield the multitracer solutions for further
experiments.
In order to evaluate the stabilities of the metalhumate complexes we employed ion exchange,
solvent extraction, ultrafiltration, and paper
chromatography. Free cations are partiallyremoved from the solutions with ion exchange
and solvent extraction. Since the fraction of thecations removed is a function of theconcentrations of the humic acids which can be
combined to the cations, we can estimate thestability of the metal-humate complexes.
Determination of stability constants withultrafiltration is based on the property of humic
acid as a polyacid; the cations bound to humic
acid molecules cannot pass an ultrafiltration
membrane. Relative radioactivity of the filtratedepends on the concentrations of humic acid in
the solution for ultrafiltration.
Paper
chromatography was used for qualitativeevaluation of binding affinity of the cations
with humic acid. Multitracers spotted on apiece of humic acid-impregnated paper wasdeveloped by an 80% ethanol aqueous solutionof manganese acetate.
Preliminary results on the complexation
affinity from a paper chromatogram indicatedthat, at least, technetium and several lanthanides
preferred to make complexes with humic acid.
Solvent extraction and ion exchange studies on
the complexation also indicated that theseelements can make stable complexes withhumic acid. Further analysis on ion exchange
and extraction properties of the resin and theextracts employed should give the quantitative
information regarding the affinity of thecomplex formation between the cations andhumic acid.
References
1) Y. Minai, Y. Meguro, and T. Torninaga: Proc. 3rd. Int.
Syrnp. Adv. Nucl. Energ. Res., p.229 (1991) and thereferences cited therein.
2) S. Arnbe, S. Y. Chen, Y. Ohkubo, Y. Kobayashi, M.
Iwamoto, M. Yanokura, and F. Ambe: Chern. Lett.,
1991, 149.
3) S. Arnbe, S. Y. Chen, Y. Ohkubo, Y. Kobayashi, M.
Iwamoto, M. Yanokura, and F. Arnbe: Anal. Sci.,
Suppl., 7,317 (1991).

* Dept. of Chern., Fac. of Sci., Univ. of Tokyo-89-

RIKEN Accel. Prog. Rep. 26 (1992)

111-3-8. Investigation of 7 MeV/nucleon 58Ni Induced Reaction
on Cu and Rh Targets
M. Kiriu, T. Saito, A. Yokoyama, E. Taniguchi,
H. Baba, and Y. Ohkubo
Linear and angular momentum transfers involved in heavy-ion collisions are fascinating
phenomena 1) and the succeeding decay mechanism is so complex that extended studies arestill required.
An experiment was performed at the E3b
beam course of RIKEN Ring Cyclotron. A 7
Me V /nucleon 58Ni beam was used to bombard
Cu and Rh targets (and Al target as a monitor)
in order to compare the mass distribution of thereaction products from an essentially symmetriccomposite system to that from an asymmetricone.
The thicknesses of a Cu target foil (foil 1)
and two Al downstream catcher foils (foil 2 and
3) were 1.84 mg/cm 2 , 2.74 mg/cm 2 and 6.07
mg/cm 2 , respectively. Not to degrade the beamenergy, all these catcher foils were placed in thedownstream.
A Rh target stack consisted of a 2.75 mg/cm 2
Al upstream catcher foil, a Rh target foil, and a
6.03 mg/cm 2 Al downstream catcher foil. The
Rh target was an about 2.5 mg/cm 2 foil with .
an about 18 mg/cm 2 polyester support in thedownstream.
The beam intensities on Cu and Rh foils wereabout 0.15 and 0.7 particle nA, respectively. After the irradiation, -y-rays from each foil were repeatedly measured with Ge detectors for about
two months. About a hundred product nuclides
were identified based on the photopeak energy
and half-life data.
The formation cross sections were obtainedfor each nuclide by decay analysis. Assuming
the charge dispersions to be Gaussian, we could
determine the most probable charge, Zp, only
for the Cu target stack because there were no
isobaric triplets for the Rh target stack.
Figure 1 shows mass yields of each Cu target stack foil, where the contribution of reaction
prod ucts with Al catchers was subtracted. Figure 2 shows formation cross sections vs. atomic
mass, where the contribution of reaction products with upstream Al and polyester could not

be subtracted.
As Fig. 1 shows, there appear a broad peakaround mass 107 for foil 3 and broad peaks aroundmass 60 for all the three foils, where the former
is due to evaporation residues and the latters are
to fission fragments. In Fig. 2 a large peak isobserved around mass 67 which is mainly due tothe reaction products with polyester. But anyother clear information could not be obtained.
We should, therefore, study further on the reaction mechanism.
IOE 4

WE3

t:
z

:::>

~-<

WE 2

lOE 1

30

50

70
MASS

Fig. 1. Mass distribution of 7 MeV/nucleon 58Ni +Cu system (See text). [foil 1 : ® , foil 2: 0 ,foil 3: • ]

IDE 1

t:
z

.• i

:::>

~-<

IDE 0

...

t· 1
..j.

I)

lOE-l

I

~

I I

i
i

...

...i

•

10E-2
20

60

100
MASS

140

170

Fig. 2. Mass distribution of 7 MeV/nucleon 58Ni +Rh system (See text).

References-90-1) R. Bass : "Nuclear Reactions with Heavy Ions" ,Springer-Verlag, Berlin (1980).

RIKEN Accel. Prog. Rep. 26 (1992)

111-3-9. Target Fragmentation of 141Pr and 165Ho Induced
by Heavy Projectiles
K. Takesako, T. Saito, H. Kusawake~ A. Yokoyama, H. Baba,
Y. Ohkubo, A. Shinohara, and M. Furukawa
In an earlier study l) for target fragmentation
by highly energetic light projectiles such as
proton and 4He, the following relationship wasshown to hold between the mass yield Y(A) andthe fragment mass number A:

Y(A) ex exp(pA).

(1)

This parameter p is known to depend only on
the incident energy for various combinations oftarget and light projectile. It was further foundthat the parameter value decreases as the incident energy increases and levels off above 1 Ge V.
We performed experiments in order to test thislimiting behavior in the case of heavy-ion projectiles.
The monoisotopic 141 Pr and 165 Ho target foils
sandwiched among aluminum or Mylar foils were
irradiated with 14N, 15N, or 40 Ar projectiles at
the E3b beam course of RIKEN Ring Cyclotron.
We performed 'Y-ray measurements with Ge
detectors to obtain the cross sections of reaction
products and the cumulative mass yields.
Figure 1 shows the values of p derived for each
incident energy. For the systems with 14N (1.89
GeV) and 40 Ar (2.36 and 3.80 GeV) the data
seem to be in good agreement with the limiting
value reported in Ref. 2.
Target fragmentation is usually treated asa two-step process, excitation by the projectile
and sequential deexcitation. We tentatively
attributed the limiting value of p to theappearance of the upper limit in the nuclear
temperature that the initially formed nuclei canpossess. We considered p to be related to themean evaporation energy per nucleon (Eev), thenuclear temperature T, and the level density
parameter a as

{Eev}

p

= aT2 .

100

(2)

Following the method described in Ref. 3, we
found that the limiting nuclear temperaturefrom our data is around 5.4 MeV as listed in

10-2---'---'--'-~

L--....I.--'--'-..............."------'----'--'-...............

10-1

10

101

0

ELAB

102

(GeV)

Fig. 1. Dependence of the parameter p on incident
energy E LAB . Circles represent the data in thiswork, and triangles the data by Cumming et al. 2 )Closed marks mean the systems with heavy-ion
projectile, and open marks light-ion projectile.
Table 1. Parameter
temperature T.

15N + 14ipr
IsN + 165Ho
14N + 165Ho
40 Ar + 141 Pr
40 Ar + 141 Prp

andded ueed

ELAB

p

(GeV)

(10- 2 )3.93±1.78
5.52±2.12
3.39±0.15
3.85±0.11
3.97±0.11

1.05
1.05
1.89
2.36
3.80

nuclearT(MeV)
5.40±2.35
4.08±1.40
5.49±0.14
5.47±0.09
5.37±0.09

Table 1. This value is consistent with various
theoretical predictions. 4)
References
1) G. Rudstam: Z. Naturforsch., 21a, 1027 (1966).
2) J.B. Cumming et al.: Phys. Rev., CI7, 1632
(1978).

3) S. Shlomo and J.B. Natowitz: Phys. Rev., C44,2878 (1991).

4) See, e.g., H.W. Barz et al.: Phys. Lett., BI84,* Tsukuba Space Center. NASDA-91-125 (1987).

RIKEN Accel. Prog. Rep. 26 (1992)

III -3-10. Symmetric Mass Division in the Ir-Composite System
S. Watanabe, K. Takesako, T. Saito, H. Baba, Y. Ohkubo,
A. Shinohara, E.Taniguchi, and M. Furukawa
A nuclear chemistry experiment with a lighttarget and a heavy projectile was carried out
to investigate the heavy-ion reaction mechanism
under the inverse kinematical conditions contrary to usual experiments. A vanadium foilwith a thickness of 8.47 mg/cm 2 was bombarded
with a 136Xe beam (8.5 MeV/nucleon) at theE3b beam course of RIKEN Ring Cyclotron.
Two Al catcher foils (5.67 mg/cm 2 thick) wereplaced downstream of the target. Irradiation
time of the stack was about 90 min. After thebombardment,
the irradiated foils wereseparately subjected to ')'-ray spectrometry withGe spectrometers. Product yields of 143 nuclides were obtained.
The charge dispersion was considered to be a
Gaussian. The most probable charge (Zp) seems
to have linear dependence on mass number A,
Zp O.39A+4.3. The product charge dispersion
for the mass region from 50 to 176 was foundto have a width parameter of IT=1.05. The total chain yields for each foil (target and two Al
catcher foils) were deduced from the obtained
width parameter, Zp, and product yields. Figure 1 shows the product-mass distributions forthe target and the two catcher foils. The tatgetlike deep inelastic transfer (DIT) products canbe observed mainly in the target, whereas the
projectile-like DIT products in the second
catcher foil. The peak around mass 170 is attributed to fusion-evaporation residues whichwere .predominantly transferred to the mostdownstream catcher.
Althoughfusion-fission
products
arereported 1) to make a broad peak in the symmetric mass region in the system of 132Xe+NATFe,
this com ponen t may be buried in the tailsof the target- and the projectile-like DIT components in this experiment. Further experiments
at other incident energies are needed to obtainclearer insights into the reaction mechanism.

10)
.D

-

S 102

't;;)

10 1

102
.D
S

10 1

=

--

10 2

.D

S

101

100 4LO--L--...lgO--.l.--l...J..20---L--l..J...60---'----::200

A
Fig.1 The mass distributions for the target (A),the first catcher (B), and the second catcher( C).

References
1) R. A. Esterlund, W. Westmeier, U. Reus, A. M.
Habbestad Watzig, and P. Patzelt: Nucl. Phys.,-92-

A435, 597 (1985).

RIKEN Accel. Prog . Rep . 26 (1992)

111-3-11. Nuclear Reactions with Intermediate Energy
Heavy Ions on V, CU, Nb, and I
E. Taniguchi, 1. Kurachi, A. Shinohara, M. Furukawa, S. Kojima,
K. Takesako, T. Saito, Y. Ohkubo, S. Shibata, and F. Ambe
Nuclear reactions induced by intermediate
energy heavy ions have been extensively
studied. Further studies are, however, stillrequired to elucidate the reaction mechanism
in detail. We have measured cross sections
and recoil properties in the reactions of V,
eu, Nb, and I with 40 Ar (38, 59,
95MeV/nucleon), 14N (135MeV/nucleon),and 15N (70Me V/nucleon) ions. The target
stack was irradiated at the falling-ball
irradiation facility 1) installed at the E3bcourse of the RIKEN Ring Cyclotron. Targets
were metal foils (10 --- 30Jlm thick) and KI
discs covered with polyester films oraluminum foils to catch the recoil products.
Non-destructive y -ray spectrometry was
perfonned with Ge detectors for three months
after bombardment. Mass yield distributions
were obtained from the measured crosssections on the basis of thechargedistributions. Mean longitudinal momentum
transfer was deduced from the measured
mean recoil ranges.
As an example, the mass yield curve of
93Nb + 40 Ar reaction is shown in Fig. 1. In
the target fra~mentation region (A=40 ---80),

the slope of the m,!\ss yield curve for
38MeV/nucleon is higher than that for
59Me V/nucleon. However, much difference
cannot be seen between 59Me V/nucleon and
95MeV/nucleon. From our experimental
data, the higher projectile energy results inthe lower slope of the mass yield curve until
the projectile energy reaches 2- 3GeV. Abovethe energy, the slope of the mass yield curve
approaches a constant value. Massdependence of the mean longitudinal
momentum transfer for the same reaction
system is shown in Fig. 2. The results showthat the mean longitudinal momentum
transfer decreases with increasing projectile
energy.
The changes of the slope of the mass yield
curve with various targets at the samebombarding energy are insignificant. The
mean longitudinal momentum transfer
decreases with the increase of the target
mass. The reaction mechanism will be
examined from detailed analysis of theexperimental data.

102

102----------------------~(!lID
Ih ~ID~<D <D <D<D~~

95MeV/nucleon:cE 102-<D<aP~t$>% ~~~ID
D :95MeV/nucleonb.. :59MeV/nucleono :38MeV/nucleon<D

59Me VInucleon

<D

~~~

100~~~--~~~~~~~
20 30 40 50 60 70 80 90 100
Mass. (~)

<D@r(

(IQ)
<D

Jijp

~

38MeV/nucleon

10;LO~2~O--3~0-4~0--5~0-6~O--7~O-8~O~90
Mass (A)Fig. 1. Mass yield distributions in the interaction of
93Nb with 40Ar ions (O:observed nuclides<30% .6:
observed nulcides~30% D:observed nuclides~60%)- 93-

Fig. 2. Mass dependence of mean longitudinal
momentum transfer for 93Nb + 40Ar reaction.

References
1) S. Ambe et at .: Chern. Lett., 1991, 149.

RIKEN Accel. Prog. Rep. 26 (1992)

111-3-12. Nuclear Reaction Products in the Interaction of 197 Au andIntermediate Energy Heavy Ions 14N, 15N, and 40 Ar
1. Kurachi, E. Taniguchi, A. Shinohara, M. Furukawa, S. Kojima,
K. Takesako, T. Saito, Y. Ohkubo, F. Ambe, and S. Shibata

Au tar~ets were irradiated with heavy-ion
beams 1 N (70MeV/nucleon), 14N (135MeV/nucleon) and 40 Ar(38, 59Me V/nucleon) to
study the projectile dependence of the nuclear
reactions including fission induced byintermediate energy heavy ions.
Irradiations were performed at the falling ball
irradiation facilityl) installed at the E3b courseof the RIKEN Ring Cyclotron. Target stacks
consisted of Au foils (37-43mg!cm 2 thick)surrounded by Mylar and aluminium catchers.
After irradiations, y -rays from the targets andthe catcher foils were measured with Ge
detectors. Mass yield distributions werededuced from measured formation crosssections (Fig. 1). Linear momentum transfer
per nucleon (vII) and isotropic momentum
components (V) were deduced from measured
recoil ranges by means of the two step vector
model 2) (Fig. 2). The products were classified
into fission (A=55-110), spallation (A= 130-180) and nucleon transfer (A> 180) reaction
products from the mass and momentum
distribution. The fission yields were obtainedby subtracting spallation components frommass yields in the region, A=59-111. The
spallation component yields were extrapolated
from the mass yields in the region of A= 135175. The fission yields were fitted to Gaussian
to obtain the fission cross section. The resultsof analysis for fission are presented in Table 1.
The fission cross section decreases withincreasing projectile energy per nucleon. The
mass of fissioning nucleus was estimated to be
160-180 from the center of the mass distribution. The vII values of fission products are
similar to those of products in the vicinity ofthe target. These suggest that these products
originate from the fission of target-like nuclei.
102~--------------~

Q
t1

~

6J¢

~~

~

><U

6
E 10

1

2
c<U

~f~

CD~
~
0

E
0

~

100~~~-~~-~~-~~

o

100

50

150

200

Mass

':i)

10

2

10

1

~J

5
"'0

~

:><

Fig. 2. Momentum distribution of products in theinteraction of Au with 15N 70Me VInudeon. Symbols
denote: 0, v II from the average forward range; .6., VIIfrom the two step model, 0: V from the two stepmodel.

•~A·,.·t0

Table 1. Parameters of fission mass distribution.

eJ

10 0 L - -_ _- - ' -_ _ _- - ' -_ _ _--'

50

100

150

Center

FWHM

(A)

(A)

Fission Cross
Section (A)

14N (135)81.4± 1.552±40.24±.06(70)87.3±.336.8±.7

0.62±.05

4°Ar (59)

89 ±7

49 ±3

0.61±.17

4 OAr (38)92.9±.2

48.9±.2

1.18±.16

15N

200

Mass

Fig. 1. Mass yield distributions in the interaction of
Au with 14N 135MeV/nucleon (solid) and 15N 70
MeV/nucleon (open). Symbol
denotes that it iscumulative yield. The other symbols indicate thefraction of each yield that was measured: .6.: <40%;
D: >40%.

°

Projectile(MeVInucleon)

References
1) S. Ambe et al.: Chern. Lett., 1991,149.
2) L. Winsberg= Nucl. Instrurn. Methods: 150, 465(1978).

-94-

RIKEN Accel. Prog. Rep. 26 (1992)

111-3-13. Time-Differential Perturbed-Angular-Correlation (TDP AC)
of y-Rays and Emission Mossbauer Spectroscopy of 99Ru in
YBa 2 Cu3 07-x Using 99Rh as a Source Nuclide
Y. Ohkubo, Y. Kobayashi, K. Harasawa, S. Ambe,T. Okada,K. Asai, S. Shibata, S. Takeno,* and F. Ambe
The perovskite-like oxide, YBa2Cu307_x, issuperconducting for Osx~0.7 (Region I), and issemiconducting for 0.7~xs 1 (Region II). Both phases
have two distinctive copper sites. The frrst site (Cu-I)
forms one-dimensional CU-O chains only in Region I.
The second site (Cu-2) constitutes a coInlgated twodimensional plane in both Regions I and II. The
variation of oxygen content involves only the
population and depopulation of one oxygen site. along
the Cu-I-oxygen chains. Thus. the copper ions at theCu-2 site exist as Cu2+ in both Regions I and II. On
the other hand, the copper ions at the Cu-I in Region I
exist as Cu2+ and Cu3+, and those in Region II Cu 1+ andCu2+. It is generally accepted that a copper ion inperovskite-like oxides is easily replaced by a metal ion
with its ionic radius close to that of the copper ion. We
flISt prepared a YBazCU3O,-x with ~0.2 (yBC07)
containing a Ippb order of radioactive 99Rh3+, which
decays to 99Ru with t1l2 = IS d. I •2) All heatingprocesses were done in flowing oxygen. We thenprepared a sample with x::::1 (YBC06) by heating the
YBC07(99Rh) sample under reduced pressure at 760°C
for I h. The ionic radius of 99Rh3+ is close to that of
Cu2+, and hence rhodium ions are expected to occupy
the Cu-I and Cu-2 sites. We measured IDPAC spectraof the 99Ru 3/2+ level (t1l2 = 20.5 ns) in the two
samples to determine the Ru or Rh site occupancy. The
emission Mossbauer spectra of the two samples were
measured at 5 K.
Figures I(a) and (b) show the frequency spectra
derived from the IDPAC spectra of 99Ru in YBC07 andin YBC06, respectively. Figure I(a) shows two electricfield gradients (EFG's) corresponding to two peaks.
These two EFG's might be ascribed to two Ru sites
corresponding to the Cu-I and Cu-2 sites. Bu~ asshown in Fig. I (b), there is only one Ru site in
YBC06 corresponding to either Cu site. We must
consider the possibility that during the heating process
under reduced pressure at 7&C mentioned above, Rh
ions at one Cu site moved to the Cu site of the othertype. In order to examine this possibility, we heated the
YBC06(99Rh) sample in flowing oxygen at 28Q°C for
0.5 h and measured a IDPAC spectrum for this sample.
We obtained an essentially identical spectrum to that of
YBC07(99Ru). At this low temperature, it is unlikely
for heavy Rh ions to move to another site. We thus
conclude that Ru ions occupy one type of Cu site andthat the two EFG's seen in Fig. I(a) correspond to two
oxygen configurations at Ru ions and one EFG in Fig.
I (b) to one configuration.

We note that the frequency distribution for YBC06 at
10 K in Fig. 1(b) is widespread. Compared to theMossbauer spectrum for YBC07. the spectrum for
YBC06 has a second component with a larger width.
From these observations, we consider that there is a
hyperfine magnetic field at 99Ru in YBC06 in addition
to the EFG at low temperatures. At least above 80 K
this magnetic field is insignificant. The magnitude of
the hyperfine magnetic field at the Cu-2 site at 80 K
was found to be comparable to that at 10 K. using 57Fe
as a probe.3) On the other hand. the magnetic field at
the Cu-l site at 80 K is a few times less than that at 10K.3) We therefore conclude that Ru ions occupy the CuI site in both YBC07 and YBC06 exclusively.
We suppose that metal ions like Rh ions which favorhigh oxidation states are hardly substituted for Cu ionsin low oxidation states. Since we frrst prepared YBC07
in flowing oxygen and the average valence of the Cu
ions at the Cu-I site is larger than that of the Cu-2 site,
Rh ions are considered to have occupied the Cu-I site.

4

~ "

iki

10 K

!~

~3~80Ki~li 2::1.~ °0 1 2

4

.5

293 K

CII

f\

80K

::1~
~ 00

1 2 3 4 5!u !~Frequency (loS radls)

l .A

293K

.§

Frequency (l08 rad/s)

Fig. 1. Frequency spectra of "Ru in (a) YB~~o,_ll(x~.2)
and in (b) YB~~o,_Il(X::: 1) at 10, SO. and 293 K clerived
from their TDPAC spectra.

References
1) Y. Ohkubo, Y. Kobayashi, K. Harasawa, S. Ambe, T.
Okada, F: Ambe. S. Shibata. and K. Asai: RUffiN
Accel. Prog. Rep., 2S, 89 (1991).
2) Y. Ohkubo. Y. Kobayashi. S. Ambe, K. Harasawa, M.
Takeda, S. Shibata, K., Asai. T. Okada, and F. Ambe:
Chern. Lett, 1992, 2069.
3) T. Shinjo, S. Nasu, T. Kohara, T. Takabatake, and M.
Ishikawa: J. Physique, 49. CS-2207 (1988).

* Toshiba Corp., R&D Cent-95-

RIKEN Accel. Prog. Rep. 26 (1992)

111-3-14. Magnetic Moment of Ru Atoms in Fe3- x Ru x Si
Y. Kobayashi, K. Asai, T. Okada, and F. Ambe

57Fe and 99Ru Mossbauer spectra were
measured on the ternary alloys Fe3-xRuxSi with
the Ru concentrations of 0.lsx~1.0. From 57Fe
Mossbauer spectra obtained at n K. the distribution of the hypeIfine magnetic fields (Hhf) at 57Fe
nuclei were derived as shown in Fig. 1. It isseen that the distribution of Hhf for O.lsx:sl.O
has two obvious peaks at about 220 and 300 kOe
as in the case of F~Si. The starting material of
Fe3Si has two obvious the distribution peaks of
Hhf at 220 and 300 kOe, on the basis of themagnetic moments (m[A, C] = 1.35 flB and m[B]= 2.20 flB). The intensity ratio of these twocomponents is roughly 2: 1. being consistent withthe relative population of Fe atoms on both sites.
The distribution of Hhf at 57Fe for RUO.1Fe2.9Si
is understood well in line with this. It is foundthat the peak position of Hhf for Fe[B] gradually
decreases and the relative intensity increases with

o

100

200

300

400

Hhf [kOe]

an increase of x. while the peak position of Fe[A.
C] increases slightly in the Ru concentration
range studied. The intensity ratio between thetwo components decreases from the value of 2
for F~Si and is reversed at 0.9<x. It is foundthat the mean value of Hhf for all 57Fe shifts
slightly to be larger with the Ru substitution. On
the other hand, from 99Ru Mossbauer spectra it isfound that Hhf of Ru atoms are distributed in a
broadened component. The values of Hhf arecalculated to be 340 kOe and 270 kOe for x=0.5
and 1.0 respectively.
In general. all the alloys which containruthenium as the main substance are nonmagnetic. In the region of 0.lsx:s1.0, the phenomenon
that Hhf of Fe[B] diminishes with Ru substitution
can be understood qualitatively by a decrease of
Fe atoms on the [A, C] sites in number. From
the result of NMR measurement. 1) Ru atoms are
expected to substitute selectively Fe atoms on the[A, C] sites with the quite dilute concentration ofruthenium (x=O.04) in this system. Hhf transferred from Fe[A, C] is reduced with the increaseof the substituted Ru atoms. It is considered.
however. that the previous result does not refer toour present study because the range of substituted
Ru concentration is different. In order to inter.pret the fact that the magnetization per chemical
fonnula in this system show little appreciablechange in spite of decreasing Hhf of Fe[B], twopossibilities can be considered~ Ru atoms on[A,C] sites possess a magnetic moment, or nonmagnetic Ru atoms enhance the magnetic momentof adjacent Fe[A. C] and/or [B]. The composition dependence of Hhf at 57Fe in the present
study indicates that the magnetic moments ofsome Fe[A. C] may be enhanced by substituting
Ru atoms for Fe atoms in [A. C] and/or [B] sites.
More quantitative discussion will be given
elsewhere together with experimental results on
the series of this system.
References
1) V. A. Niculescu, T. J. Burch, and J. I. Budnick: J.
Mag. Mag. Mater. ,39, 223 (1983).

Pig. 1. Hy~rfine magnetic field distribution at 57pe
nuclei of the ternary alloys Pe3-xRuxSi.

-96-

RIKEN Accel. Prog. Rep. 26 (1992)

111-3-15. The Influence of Light Element Mixture on the Lifetimeof Carbon Stripper Foils
I. Sugai, M. Oyaizu, M. Aratani, and M. Yanokura

We have been investigating the best methods
to make not only long lifetime, but alsomechanically strong carbon stripper foils withhigh reproducibility.1,2) Through a series ofrecent experiments, we developed a qui te new
type method,3) which was based on the ion
beam sputtering(lBS).
In that work the
lifetime of foils was strongly affected by theamount of hydrogen, nitrogen and oxygen lightelements in the foils.
In order to confirm the effect of the amountof light elements used as the reactive ion beam
to sputter carbon on lifetime, we made foils byusing single gases H2, N2 or 02, or binary
mixing gases such as diluted (H2 + Ne), (N2 +Ne) or (02 + Ne), and compared the lifetime
with those of foils made by the thermal
evaporation methods. All foils have surface
densities of 15 to·25 Jlg/cm 2 and their size is 15
x 15mm2 .

The lifetime measurements of foil werecarried out by 3.2 MeV Ne+ beams of intensityof3 - 4 JlA from the Van de Graaff Accelerator
at the Tokyo Institute of Technology. The
lifetime was defined as an integrated current
incident upon the foil till rupture.
The contaminants of light elements such as
H, Nand 0 in the foils were examined by
ERDA (Elastic Recoil Detection Analysis) andRFS (Rutherford Forward Scattering) methods
using 50 Me V Ar4+ beams from the RILAC.
Figure 1 shows the result of lifetime
meaurement of the foil made by the single andbinary mixing gas methods, together with thatof a commercially available carbon(CM) foil.
As shown in the figure, an extraordinarily long
lifetime was achieved in the case of ion beam
sputtering of reactive single nitrogen(lBSRN),
and the foil made by binary mixing gas of (N2+ Ne) also shows rather long lifetime. On theother hand, we can clearly see that foils madeby the single or binary mixing of hydrogen or
oxygen gases had very short lifetimes. The
lifetime of a foil made by the thermal
evaporation method is nearly the same as thatof a CM foil. As a reference the lifetime of thefoils made by the IBS of Ne gas is shown in
Fig.l.

120: Binary Mlxlno r.a~1Iv. I Single
Inerl gas
: oas Ion beam
Ion beamI

Slnole reacOve
oas Ion beam
100

0

e-

80

Q)

.§

-;
(;

(N2 +Ne)

co I
E
G;

~

I(5)

I
I

:::E

u

2- III
I
:2 II

(15)

(1 O) :

~
20

2

( 14)

a.
«I
>
Q)

60

]i
:::i

N

.2

g

I
I
I
I
I
I

Ne
1(8)

I

(3)

(5 )

(4 )

(5)

I

Various types of ion beam

Fig.l. Comparison of relative lifetimes of foils madeby different types of gas ion sputtering.
The
lifetimes were measured by using 3.2 MeV Ne+
beams of 3-4 JlA intensity. The foil thickness was
about 15 Jlg/cm2. The average total incident current
in mC(milli-Coulomb) until rapture is plotted with
the number of samples investigated in parentheses
beside the point.

It is worth while to notice that the foils madeby the binary mixing gas of (N2+Ne) have thelongest lifetime among the binary mixing
gases, but the life is shorter than the IBSRN,
and the foils sputtered by the single or mixingof hydrogen or oxygen gases show a shorter
lifetime than a eM foil.
The admixture of oxygen or hydrogen incarbon foils always reduces the lifetime. The
bondings between carbon and nitrogen atoms
in the foil are probably stronger and morestable than those of hydrogen or oxygen atoms
for the beam bombardment.
The most important point in prodution of
extraordinary long-lived foils is to reduce theamounts of hydrogen and oxygen contaminants
as much as possible.

References
1) I. Sugai et al.: Nucl. Instrum. & Methods. Phys. Res.,
A236, 576 (1985).
2) I. Sugai et at.: Nuc1. Instrum. & Methods. Phys. Res.,
A282, 164 (1989).
3) I. Sugai et at.: Nucl. Instrum. & Methods. Phys. Res.,
A303, 59 (1991).

- 97-

RIKEN Accel. Prog. Rep. 26 (1992)

111-3-16. Positron Annihilation Study on Nanometer Cavities
in Porous Silicon
Y. Itoh, H. Murakami, A. Kinoshita,* and R. Iwata)!:)!:A porous silicon obtained by anodization of a silicon
crystal in hydrofluoric acid contains a network of nearlyparallel pores. The physical and chemical properties ofporous silicon have attracted strong attention. The
photoluminescence was found out recently from a
porous silicon}> The mechanism of the photoluminescence is actively studied while the utilization is
discussed as an optical device and a gas and humidity
sensor. The surface of pores is covered by an Si-H layer.
The study of an Si-H layer is interesting from a view
point of positronium chemistry and surface science.
Silicon substrates used were boron-doped wafers of 1...,2
ohm-cm with (100) surface. The substrates wereanodized in hydrofluoric acids of 20 wt. % - 55 wt. % at aconstant current density from 10.2 mAlcm2 to 100.0
mA/cm2. The thickness of a porous layer ranges from30.0 nm to 100.0 nm. The porosity. which is defmed
as the ratio of the reduced mass from the anodized layer
to its mass before the anodization. varies from 0.526 to
0.686.
Measurements of positron lifetime and Doppler
broadening were carried out on the anodized samples
sandwiching a positron source of 22NaO. Some of thesamples were mounted on a heating stage in a vacuum
chamber with a positron source of 48V and evacuated to
3 x 10-6 Torr at 350 °C for 4 hr. The spectra of lifetimeand Doppler broadening were obtained before and after
the evacuation as keeping the sample on the stage in thechamber. The positron lifetime was measured with afast-fast coincidence system whose time resolution is
210 ps. The Doppler spectrum was obtained with the aidof a pure Ge detector. The energy resolution of thesystem is 1.07 keY. The lifetime spectra were analyzed
with a computer program POSITRONHT (Kirkgaard).2>
A very long lifetime is clearly observed on porous
silicons of #1. #2, and #3 as shown in Fig. 1. The
pick-off annihilation of ortho-positronium corresponds
to the long lifetime. A value of the lifetime is about a
few tens of nanoseconds which is anomalously long as apositronium lifetime in a solid except for a few kinds ofzeolites (Ito et al.).3) Fig. 2 shows Doppler spectra forthe porous silicon of #2 (a) and the bulk silicon (b).
A narrow component seems to be overlapped on a broad
gaussian component. This suggests the parapositronium formation in a porous silicon. A
positron/positronium spectroscopy is very useful in the
study of physical and chemical properties of porous
silicon. The effect of hydrogen on the surface in the poreis under investigation ..

10 5
Porous 51"
Porous 5112·

10·

PorQUS ~,f3:

BullfSJ

0Q)
.!!!.
(/)
~

10 3

z

::>

0
0

10 2

10

1

0

200

400

600

800

1000

CHANNEL NUMBER

Fig. 1. The lifetime spectra of porous silicons (#1, #2, #3)
compared with bulk silicon.

l'J

c
::s
o

U

(b)
:l

c
::s

8

510

511

520

Energy (Ke V)

Fig. 2. S-parameter of porous silicon (a) compared withbulk silicon (b).
References
1) L. T. Canham: Appl. Phys. Lett.• 57, 1046(1990)
2) P. Kirkgaard, M. Eldrup. O. E. Mogensen, and N.
J. Pedersen: Computer Physics Commun.• 23,
307 (1981).
3) Y. Ito, T. Takano, and M. Hasegawa: Appl. Phys.,A45, 193 (1988).

* Fac.of Sci.and Eng. Tokyo Denki Univ.
** eyc. RI center, Tohoku Univ.
-98-

RIKEN Accel. Prog. Rep. 26 (1992)

111-3-17. Recovery and Clustering of Defects in GaAs Studied
by Means of Positron Annihilation
Y.ltoh, H. Murakami, and R. Iwata*
The identification of induced defects and the recovery
stage of electron-irradiated GaAs have been studied bypositron lifetime and Doppler broadening measurements.
Samples used are liquid encapsulated Czochralski(LEC)
GaAs whose carrier density is 2.03 x 1017 cm-3 . Someof the LEC-GaAs were doped with Si atoms of 1.3 x
10 18 cm- 3 . They were irradiated by 3 MeV electrons toa dose of 5 x 10 17 cm- 2 . The irradiation temperature
was held below 50 t. The irradiated samples wereisochronally annealed for 30 min at various temperaturesfrom 373 K to 973 K and measured at 300 K after eachannealing. Some of the irradiated samples were cooled
down to a temperature below 300 K to 10K andmeasured at the temperature. 22Na was used as apositron source. The lifetime was measured with a fastfast coincidence system whose time resolution is 210
ps. The Doppler broadening was obtained with the aid ofa pure Ge detector whose energy resolution is 1,(17 ke V.
Figure 1 shows temperature dependence of lifetime(a)and S-parameter(b) of electron-irradiated undoped and Sidoped GaAs. The lifetime decreases as the temperature
decreases. The lifetime of 260 ps at 300 K is classified
as a gallium vacancy V Ga .1-3 ) The charge state of VGa is
considered to change from a negative state to a neutral
state as the temperature decreases since V Ga is anacceptor type defect. l ) Then the lifetime is expected toincrease as the temperature decreases but the obsetved
lifetime shows an opposite tendency. One possible
explanation is deduced from the coexistence of antisite

Ga, GaAs , induced upon the irradiation, together with
VGa' GaAs is considered to act as a weak trap of positron
at low temperatures. The lifetime of positrons trappedby this shallow trap is shorter than that in VGa' The
decrease of S-parameter as the temperature decreases
supports strongly the coexistence of GaAs and thisconclusion agrees with the proposal by Corbel et al.3)
The lifetime and S-parameter of electron-irradiatedundoped and Si-doped GaAs change during theisochronal annealing as shown in Fig. 2(a) (b). Twoannealing stages were observed in the both samples.
This suggests that VGa's gather and form clusters in thelower temperature stage, and the clusters are annealed
out in the higher temperature stage. The effect of Si
dopants shifts the annealing stage to the higher
temperature. The detailed discussion was presented in
UN3PC92 conference.
270

260
Ci)
0-

P

9

250

240
0.48

Gi 0 .46l)

E 0 .44270f.

ca 0 .42(alC.

en 0.40
0.38200

400

600

800

1000

Temperature (K)Fig. 2.Isochronal annealing of the positron lifetime andS-parameter in electron-irradiated GaAs; (II) undoped and(e )Si~oped samples. The results obtained before
irradiation on undoped 0) and Si-doped (0) samples arealso included.

References
G. Dlubek, A. Dlubek, P. Bremmer, K. Frieddland and
R Rentszch,: Pbys sat. sol. (a), 106,419(1988) '; G.
Dlubek, A. Dlubek, R Krause,and O. Brummer: Phys.
stat sol. (a), 107 1111 (1988).
2) S, Dannefaer, B. Hogg and D. Kerr. Pbys. Rev. ,830, 335 (1984).
3) C. Corbel, M. Stucky, P. Hautojarvi, K. Saarinen, and
P. Moser: Phys. Rev. t B38, 8192.(1988) ; C.
Corbel, F. Pierre, P. Hautojarvi, K. Saarinen~and P.
Moser: Phys. Rev' 1 841, 10632 (1990).
1)

0.460

50 100 150 200 250 300 350

Temperature (K)Fig. L Temperature dependence of positron lifetimes(a) andS-parameter(b) in undoped(. and Si~oped (e) GaAs
irradiated with electrons. The results obtained before
irradiation on undoped (0) and Si~oped (0 ) samples
are also included.
• Cyc. RI center, Tohoku Univ.

-99-4. Radiation Chemistry and Radiation Biology

RIKEN Accel. Prog. Rep. 26 (1992)

111-4-1. LET Dependent Competition between Radiative and Nonradiative
Annihilations of Core Holes Produced by Ion
Irradiation of BaF2 Single Crystal
K. Kimura, R. Nemoto, S. Nakamura, K. Morita, and H. Kumagai
VUV-photon or electron excited BaF 2
single crystal is known to exhibit a2200 A luminescence band.
Thisluminescence is named the Auger-freeluminescence in the sense that thevalence electron of F2p transits to thecore hole of Ba5p radiatively . instead ofemission of Auger electrons. One ofcharacteristics of this luminescence isthat its decay time is as short as 800
ps,which cannot be explained by selftrapped excitons. We have measured
luminescence decay with various
ion
irradiations, using 8I8p l ) which is anequipment for measurement of fast
luminescence decay. Results weredifferent from those of the photoirradiation. The decay could be
decomposed into two exponentials. A fastcomponent decreases in its decay timewi th increasing LET (1 inear energy
transfer of ions), while the decay timeof a slow onel,hows no systematic
variation to LET although the value for
He ions is too large ( Table l). These
resul ts can be explained by thefollowing model 2 ). In case of the ion
irradiation, there exist free electronsejected at a high density and they canrecombine
wi th
the
core
hole
competi ti vely wi th the Auger-free
ltnninescence process ( 8ee Fig. l). From
competi tion kinetics, the instantaneous
luminescence I(t) can be expressed as,

c.b.

~~~~

Rydberg:Fig.1.A competition between nonradiativetransition and Auger-free luminescence.

where k1 denotes the rate constant of
the Auger~freeluminescenceandk 2 [efree 1, that of above nonradiative
recombination. LET dependence of thelatter can be plotted as Fig. 2. The
value attains to a constant value at LET
of 15 MeV/cm2 /mg due to that for Krions. A reciprocal of the value ceiledmeans a life time of the Ba5p core
exciton.

4~---------------------°o~--~----~--~~--~

5

10

15

LET/MeV cnfmg-1

Fig.2.k 2 [efree] as a function of LET.
Table 1. LET-dependent decay times.

Excit. VUV-light He
fast/psslow/ps

800

440
1500

N

Ar

Kr

Xe

300
814

240
800

220
790

220
840

Referencesl)K.Kimura, T.~atsuyama, and H. Kumagai:
Radiat. Phys. Chern. 34,575 (1989) ;K. Kimuraand H. Kumagai: to be publ ished in
Radiat. Ef. Defect. 801.126, Dec.(1992)
2) K. Kimura and J. Wada: submi t ted toPhys. Rev. Let.

-101-

RIKEN Accel. Prog. Rep. 26 (1992)

111-4-2. Depth Resolved Dynamics of lon-tracks
Correlation between VUV - and VIS-Excimer Luminescence from
Ion-Irradiated Dense Helium
K. Kimura, R. Nemoto, S. Nakamura, and K. Morita
A track scope, composed of animaging quartz fiber and a positionsensitive photon counter, was developed.
Luminescence spectra,
their specificintensities dL/dx,
andefficiencies
dL/dE, were measured as functions of thehelium density and of depth along the Nand He-ion tracks in dense gas andliquid helium. Observed visible
ltnninescences were 1 imi ted to those due
to Rydber~ states of excimers, 3d , 3n,11, and J, according to Herzberg's
notation. It can be concluded that they
are produced only by the bimolecular
reaction of the lowest triplet excimer,
3a , and that excess energy of thisreaction must be removed by the thirdbody. With increasing penetration depth,
dL/dx was enhanced and exhibited a peakmaximum whose position depends on thehelium density. This behavior of dL/dx
could be expressed by the excitation
density (Fig.1). In an extreme case near
the track termination, dL/dx was turned
to be suppressed. A new-type quenchingprocess that the three-body reaction

cannot find the third body except for
the excimer 3 a could explain the
result.l )Also, depth-resolved VUV(vacuum
ultraviolet)-luminescence due to thetransition lA_IX has been measured on adense helium target with variation ofhelium densi ty.
Wi th increasing
exci tat ion density, the formation of lA
is enhanced by 3a +3 a reaction andsuppressed by 3a +3a +3a reaction, as was
the case of VIS-luminescence. However,the dL/dx peak shifted to smaller
excitation density. An additional peal{in luminescence efficiency dL/dE ,appeared near 4.8xl0 2 em/sec of ion
veloci ty , was much more intense thanthat for VIS-dL/dE(Fig. 2). The peak was
explained by charge exchange and direct
excitation processes~)

1000
W
"0

"-1

500

"0

x

'g

"..J

O~~~~~~~~~~~~~~

1

1
L-

1000

v( 1 Q'cm/s )

500

'g

0

0
p dE/( E dX )Fig.l.VIS-dL/dx vs excitation density
induced by 4MeV/amu N ion with various
helium densities from 0.02 at top to
0.0638 g/cm3 at bottom.

Fig.2.VUV-dL/dx vs N-ion velocity inhelium at the densities from 0.02 at
top to 0.062 g/cm3 at bottom .
References
1)K.Kimura, Phys. Rev. A to be publishedin Vol47 Jan. (1993); Nucl.lnstrum.Meth.
B53, 301(1991)
2)K.Kimura, Nucl.Instrum.Methods B, inpress.

-102-

RIKEN Accel. Prog. Rep. 26 (1992)

111-4-3. Radiation Effects of lon-particles on Various

DNA Structures
S. Kitayama, K. Nakano, T. Takahashi, M. Suzuki, M. Kikuchi, and H. Watanabe*
Ionizing radiation including 3:ccelerated
particles induces various damages In DNA ofliving cells. Although most of them arerepairable in the cell, unrepairable damages arethought to be the cause of cell inactiyation.
However, little is known about what kinds of
DNA damage are unrepairable in the l~ ving
cells. It is also unknown whether unrepatrable
DNA damages are qualitatively. andl?rquantitatively different in eukaryottc or In
prokaryotic cells. In eukaryotic cells double helical DNA coils around histone hexamers(=beads). These beads make a helical st~ng ofthem with HI histone and other non-hIstone
proteins. The native .DNA is wrapped ~urther
into a structure of hIgher order by tyIng up
these strings in a bundle. Therefore, it can be
expected that the type and lor num~er ofradiation damages in a naked DNA mIght bedifferent from those induced in the folded
structure such as chromosome. In prokaryotic
cells double-strand DNA is also folded withmany DNA binding proteins and bi~d~ to t.hecell membrane. From these reasons It IS qUIte
important to avoid the art:ifici~ d~age during
the extraction and analysIs of IrradIated DNA.
Recent technical progress in the analysis of alarge DNA, such as the pulse field gelelectrophoresis, makes it possible to measure
the strand breakages in a large DNA. Wholechromosome of bacteria such as E. coli is theorder of -1(/J base pairs (bp). Therefore, it can
be cleaved at defined positions with arestriction endonuclease into several fragments
which have hundreds kilo bp.
Using thistechnique it is possible to comp.are radiation
damage in each DNA. fragme~t In ?~ntrast to
analyze the damages In an unIdentIfIed gross
DNA fragment mixture.
In order to compare the radiation effects of Nions (,.." 135 Me VI~) on naked, folded or
packaged DNA in a cell? ,:e~ls of J?einococcus
radiodurans were solIdIfIed WIth agarose.
Before the irradiation the cells were lysed in thepresence of RNases and treated with or without
proteinase.
The "naked", "folded" or"packaged" DNAs were i~adiated wi~h various
doses of the ions. FollOWIng the lySIS of cells
and treatment with proteinase, DNAs weredigested with a restriction endonuclease. Not
I, and analysed by the pulse. field gelelectrophoresis. This enzyme. dlgeste~ theunirradiated chromosomal DNA Into 11 pieces
whose sizes are as follows; 216, 230, 253,
277, 303, 307, 320, 365, 388, 418 and 498
kbp.1).
A preliminary experi~ent. w~ carned out todetermine the dose of IrradiatIon adequate tofind out the change of DNA fragments listed
above. It was observed that bigger DNA
fragments of a "folded" DNA disappeared
substantially in contrast to those of other two
samples. The figure will ~e presente~ after
confirmation by more detaIled expenments
since the result was observed once at a dose ofirradiation.
References* Japan Atomic Energy Research Institute- 103 -

1) 1.K. Grimsley, C.I.Masters, E.P. Clark, and K.W.
Minton: Int. J. Radial. Bioi., 60, 613 (1991).

RIKEN Accel. Prog . Rep. 26 (1992)

111-4-4. Further Studies on Sensitivity of XP Cells to
Heavy Ions
F. Yatagai, K. Nakano, K. Eguchi, T. Kanai, T. Takahashi, and F. Hanaoka
Xeroderama pigmentosum (XP) is an autosomal
recessive human disease, clinically characterizedby high incidence of skin cancers on sun exposed
areas. XP cells are hypersensitive to killing by
ultraviolet light (UV) due to their defect innucleotide-excision repair of UV -induced DNA
damages1>. Genetic complementation analysis bycell fusion has identified 7 genetic
complementation groups, designated groups A to
E, G, and variant.
In this study, we planed to get some insights
into the possibility that DNA damages,
reparable by the same nucleotide-excision
pathway as that for UV lesions, are also
produced by heavy-ion irradiation. As well as
normal human fibroblast cells (NB-l), XP cells ofcomplementation groups, C and D, were exposed tocarbon ions (135MeV In) accelerated by thecyclotron.
Linear energy transfer of the carbon
ion corresponded to 22.5 keY /~m. The survival
curves in Fig.l demonstrated that the radiosensitivity for XP-C cells was a little higher
than those for NB-l and XP-D cells.

An analysis by the natural elution technique
was made to explain this small difference in thesensitivity by the DNA double-strand breakage(dsb) remaining after -15hours post-irradiation
incubation. Unfortunately, comparison between
XP-C and XP-D revealed almost no difference inthe relative number of remaining dsb (Fig.2). For
better understanding, the relative number of dsb
following Co-60 gamma rays irradiation was
also shown in Fig. 2 and those data do notcontradict with the small decrease in the killing
effect compared to that by carbon ion (22.5
keY Illm).

In this elution analysis, there is a possibility
that we could detect not the damages related tothe excision repair but only the dsb induced bydirect hit of c-ions and its high-energy secondary
electrons.
o- . - CoIXP-C

0.08_ . CoIXP·O- 0- C1351XP-C...

•• .:.. C1351XP·O,

u 0.06

,I

(U

,

c

:0
~

I

. CI)

NB-1

U
(j)

A

Xp-c

"0
C

--

10

0

XP-D

Cii

...

(U

~
0

I

o

>

,.

,
..

/

.:

'

,t,r

•

•

,/"

0/./0

0.02

.../ . './~.
/ ' ,.('-/' , , '

1

I

1,-/
I

( I)
L-

0

...
,

I

u.

0

I

I

0

0

;:.".-0'

o

">
L-

:J
(J)

.0.02 .....................-'--......................-'--......................-.a................a...-.o-.a.........................- '

0.1

·20

o

20

<40

60

80

100

Dose (Gy)o. 0 1'----'----0:'-----'---...1....--..1-_-'-_-1..

o

1

2

345
Dose(Gy)

6.

7

Fig.1. The survival curves of XP and NB-1 cells forcarbon ion (LET=22.5keV / f.lm)

Fig.2. The neutral elution analysis for dsb remaining
after -15 hours post-irradiation incubation. Strand
scission factor was calculated from the relative
radioactivity remainig on the filter to the total,reflecting the relative number of dsb.

References
1) K. Tanaka: Cell Technology., 9,972 (1990) .

-104-

RIKEN Accel. Prog. Rep. 26 (1992)

111-4-5. Effect of Carbon Beam Irradiation on
Human Monolayer Cells
H. Ito. S. Yamashita, 1. Nishiguchi, * W. Ka, * F. Yatagai, and T. Kanai
This study was performed to determine thebiological effect of carbon beams on humanmonolayer cells (HeLa, RMUG). comparing
with that of 200kVp X-rays. Carbon beams
were generated by the Riken Ring Cyclotron.
The cells were maintained in an FlO medium
with 10% fetal bovine serum in a 5% C02
incubator. The cells in a proliferative phasewere irradiated at room temperature. The
irradiated cells were trypsinized and survival
curves were determined by the colony assay.
"Figure 1 (left)" showed the relationshipbetween the linear energy transfer (LET) andrelative biological effect (RBE) at a 0.1
survival.
The increase of the RBE wasobserved in both cell lines according to theincrement of the LEf of carbon beam between
20 and 80keV/J4m. The RBE depended on thedose of irradiation at higher LET region(SOkeV/J4m) and the increase of the dose from
O.SGy to 3.2Gy decreased the RBE from 2.9 to
2.7 (Figure 1 right). The recovery between
split doses was expected. since the survival
curves of both cell lines irradiated with
20keV /J4m carbon beams showed the initialshoulder (n=1.4).
Figure 2 showed therecovery between two split doses (4 hours
interval). When RMUG was irradiated of 4Gyof 200kVp X-ray (in split dose experiment,
2Gy x 2). the recol'ery rate between two split
doses was 1.7. (Recovery rate was calculatedby dividing the surviving fraction with split
irradiation by that with single irradiation.)
RMUG irradiated with 20keV/J4m carbon
beams (2Gy x 2) showed the recovery rate of
1.4.
The recovery between split do s eirradiation was observed in both X-ray andHowever, thrcarbon beam irradiation.
recovery rate was smaller in carbon beams.
The cells irradiated with higher LET than
40ke V/J4m did not show recovery between split

doses. HeLa showed the almost similar results
to RUMG.
These results suggested that the fractionatedradiotherapy might give some benefits to thenormal tissues if the normal tissues in theirradiated volume were given with the low LET
beams.

3

ij
~

Ui

'jij
(J

'61
0

'0
iii

,~
-c;

2

Qj

a:

20

40

60

80

2

0

Fig.l.

4

6

Irradiation Dose (Gy)Linear Energy Transfer (keV /Jlm)

RBE plotted against LEI' (left) and dose (right).

toA)RMUGc;.:.~.. ..

8) HeLa

4 hoIn inlelYll

. .,
'

~,>

...

"j

'b, • ",\\j """\.. 't."~\o 200KVp X~yA
D

2X 10.3 '-------'-_..1.....-----'-_-'-o
2
4
6
8

0

2O!<eVljlm
40KeVijim

2

4

6

8

10

Irradiation Dose (Gy)Fig. 2. Survival curves which were irradiated with either
single doses (open symbols) or two split doses (closed
symbols).

* Keio Univ.
-105-

RIKEN Accel. Prog . Rep. 26 (1992)

111-4-6. LET Dependence of PCC Breaks in Human
Embryo Cells Irradiated with Carbon Ions
M. Watanabe, M. Suzuki,* K. Suzuki,** K. Nakano, F. Yatagai, and T. Kanai
The technique of premature chromosome
condensation (pee) is very useful in detecting
both radiation- and chemical-induced damages
since the cell cycle delay after irradiation needs
not to be considered. It may be a powerful
method to compare effects of high and low
linear energy transfer (LET) radiations which
may produce difference in the cell cycle
progression after irradiation (1). X-ray-induced
damages have been investigated using the PeC
technique by several investigators and their datasuggested that the PCC technique is a very
sensitive method for detecting chromatin
damages (PCC) in interphase cells. Limited
reports, however, have been publishedconcerning chromatin damages induced byhigh LET radiations. Bedford an Ooodhead (2)reported the dose-response relationship of thechromatin break formation induced by alphaparticles. They showed that the chromatin
breaks increased linearly with absorbed dose in
the case of both alpha particles and X-rays.
However, the relative biological effectiveness(RBE) for alpha particles was 2.3 times larger
than that for X-rays. Goodwin at al. (3)studied biological effects of Ne ions (LET=
182keVfum) and X-rays, and found that theamount of chromatin breaks by Ne ions was
1.5 times more than that by X-rays. In
addition, although 90 % of the chromatin
breaks induced by X-rays were rejoined within
8 hours after irradiation, only 50% of thechromatin breaks induced by Ne ions wererejoined. These data suggest that high LET
radiations are more biologically effective in
producing chromatin damages than low LET
radiations. We previously reported that 14N
and 4He ions were more effective in cellkilling, mutation, PCC breaks and neoplastic
cell transformation than gamma ray in SHE
cells (1,4,5).
In this study, we detected chromosome
aberrations as chromatin breaks in 01/00
interphase human embryo (HE) cells using the
PCC technique. We assessed the RBE of theinduction of chromatin breaks induced bycarbon ion and examined the repair kinetics toqualitatively determine the difference in pee
damages induced by carbon ions with several
LETs( 22, 39,68,75,110 124, 148, and 230
keV/um). HE cells were irradiated with carbon
ions (135MeVfum) generated by the cyclotron
at the Institute of Physical and Chemical
Research in Japan. Irradiated HE cells werefused with mitotic XP cells by the polyethylene
glycol mediated cell fusion to induce PeC.
The incidence of chromatin breaks in cells
irradiated with carbon ions was higher thanthat in cells irradiated with 137Cs gamma-rays.
The RBEs, compared to 137Cs gamma ray,were between 1.8-2.3 for carbon ions when
they were compared at the same absorbed doselevel and the highest value was 2.3 for
110 -124 keV/um carbon ions. This LET
dependence is coincident with those forinduction of mutants at HGPRT locus and forthe degree of lethal effects. Although over 90% of pce breaks induced by gamma ray wererejoined within 8 hours of the post-irradiation
incubation, only 50-75% of the initial breaks
were rejoined. In the case of 110-124 keY fum
carbon ions, degree of unrepaired breaks at 12h after irradiation was 50% of initial breaks
and it was the highest value. If protein
synthesis in irradiated cells was inhibited, there
were no difference in the incidence of PCC
breaks. This suggests that newly synthesized
protein(s) may play an important role to makeLET -dependent-differences in biological effects
by high LEI' radiations.
These results suggest that there is a qualitative
difference in the chromatin damage caused byhigh LET radiations and low LET radiations.
References
1) M.Watanabe, M. Suzuki, K. Suzuki, and K. Watanabe: In Vitro Toxicology, 4, 93 (1991).
2) J.S Bedford, and D.T.Goodhead: Int. J. Ra da it. Bioi.,
55, 211 (1989).
3) E. Goodwin, E. Blakely, G. Ivery, and C. Tobias: ;Adv. Space Res., 9, &3 (1989).
4) M.Suzuki, M.Watanabe, K. Suzuki, K. Nakano, I.
Kaneko: Radiat. Res., 120, 468 (1989).
5) M. Suzuki, M. Watanabe, K. Nakao, K. Suzuki, and K.
Matsui: Int. J. Radiat. Bioi., 62, 581 (1992).

* Division of Radiation Biology, Dept. of Health Sci.,
Nagasaki Univ.

** Division of RAdiation Biology, School of Medicine,
Yokohana City Univ.

-106-

RIKEN Accel. Prog. Rep. 26 (1992)

111-4-7. Tumor Control Probabilities and Tumor Growth Delayafter Accelerated Carbon Ions
K. Ando, S. Koike, M. Kimoto, M. Iizuka, T. Kiuchi, * T. Aruga, * W. Shimizu, *T. Sugita,* C. K. Cho,* T. Kanai, H. Kato,* and F. Yatagai
proximal SOBP, and mid SOBP were
56.40y, 58.3 Oy, 36.50y, 35.80y,respectively (Fig . I).
Comparisonof these values to reference ones
indicated that
RBEs (y IC) were
1. 5 for unmodulated pi ateau,
1.4
forentrance,
and
2.3
for
both
proximalandmid
SOBPs . . Fastneutrons gave a TCD50 of 28.20y
and a resultant RBE (y In) of 3.0.
For second experi ments where thetumor growth delay was measured, a
2nd generation range modulator was
employed. The tumor growth wasmeasured by calipers every day after
irradiation, and the tumor growth
delay relative to untreated controls
wasobtained(Fig.2)
Dataofcombined four experiments indicatedthat RBEs of mid SOBP and distal
SOBP at lOy were as large as 7.0,
and that RBEs decreased when dose
increased (Fig.3).
At a high dose
region,fast
neutrons again
gavelargerRBEs than carbons.
Theseresults suggested that both oxygen
enhancement ratio (OER) and oxic
cell kill effects would be larger for
carbon ions than for fast neutrons.

Biological effects of carbon-12(135MeV/n) accelerated by RIKEN
Ring Cyclotron were investigatedfortransplantable
NFSa
fibrosarcomas growing hind legs insyngeneic C3H male mice.
Underpentobarbital anesthesia, right hindlegs with tumors (7mm diameter)
w ere 'p 1 ace d i n ado ugh nut - s hap e dradiation field with a 2.5cm rim. A
Bragg peak of carbon beams was
spread out by a range . modulator toa3-cm
width.
The
leg
tumorsreceived single doses of carbon-12
with Spread-Out-Bragg-Peak (SOBP)
andunmodulated
plateau.
As
references,
Cs-137y -raysandcyclotron-produced
fast
neutrons(13MeV) were also used here. For
initialexperiments,a
1stgeneration
range
modulator
wasused togenerate SOBP.
Tumor
control
probabilities
were
de t e r min e d.1 2 0day s
aft e rirradiation.
TCD50/120 (radiation
do ses for hal ves of mice to ac hi eve
tumor
cure
120
days
after
i r r ad i at i on )aft e r u n mod u I ate dplateau, entrance to SOBP,

B~--------------~• ~ •• a.

100

~

c..

BO

~ 60

i
e
Do
.&l

e 40
~
0

u
~

E 20

:J

t-

i.'.'¢ b....I

/'1

I

I
r/tf !. ~"O_ Ii;
do
.'0>

o

1

;0

lSI

f: II;

?

~.

0...

I

10

0

0

~

/,111

_/0:/

1 ~f
3

]

• o! .../
«

•

q:

Z

_ ...

III

/

'1-_

-C.--DIS=T.PE=-Id(..... l(;.MID.PEAK... C-PROX.PEAK

0

i ...

r.-

2

'

0'0

111, 111

I>

rEJm::)IIII

GAMlAAAAY~.IIIrr{/,~--------------~

20

40

60

BO

100

DOSE (Gy)Fig.! Tumor control probabilities after
fast neutrons(_), y rays (<», carbon
unmodulated plateau (0), entrance CA.),
proximal (.) and middle (0) of SOBP.

o

10 20 30 40 50

60 70 BO

DOSE(Gy)

Fig.2 Dose-tumor growth delay
relationship.

* Nat I . Ins t. R a di 0 I. Sci.
-107-

\
\

ia 6
a:

\

01

\
\
\

E

~ 5

Cl

\

~ 4

/\"

,~.

Q;

a:

'It

.. 3

w
a:

...... "

"

•• _

..

m

,L-______________
o

2

4
6
OOSE(Gy)~'0

Fig.3 RBEs of carbon-12 and fastneutrons relative to Cs-!37 'Y rays
for tumor growth delay.

RIKEN Accel. Prog. Rep . 26 (1992)

111-4-8. Early Skin Damage in Mice after Single Doses ofAccelerated Carbons
K. Ando, S. Koike, M. Kimoto, M. Iizuka, T. Kiuchi*, T. Aruga, * W. Shimizu, *T. Sugita, * C. K. Cho, * T. Kanai, S. Furukawa,* H. Kato,* and F. Yatagai
Biologicaleffectsofcarbon-12(135MeV/n) accelerated by RIKEN Ring
Cyclotron were investigated for a leg
skin of C3H female mice.
Two spots
we ret a tt 00 e d wit h In di ani n kin t o t heskin of outer side of right hind legs prior
to irradiation. The distance between the
spots wasmeasured one month after
irradiation,
andcomparedwiththepreirradiated value to obtain percent skinshrinkage. Skin reaction was also scoredby a s c 0 ri n g met hod w h i chi s con v e n i e n t
butsemiquantitative.
Mice
were
anesthetizedbyaninjectionofpentobarbital, and their right hind legs
wereplacedinadoughnut-shaped
radiation field with 2.5cm rim.
' Single
doses were used.
Unmodulated carbon
beams entered through the outer skin oflegs. Skin shrinkage at Day 30 indicatedthatthebiologicaleffectivenessofcarbon -12 relative to y rays (RBE) was
ran gin g fr 0 mI. 5 to 4. 0 ,de pen din g 0 n
the Ii near energy transfer . (LET) and on
the severity of damage (Fig.I).

Skin shrinkage increases with a dosedependent fashion till certain doses overwhich saturation of skin shrinkage wasobserved for all four different LETs ofcarbonbeam (Fig.2).
HigherLETs
showeda lower saturationlevel thanlower LETs. As the highest
LET used
here(lOOkeV/,u m)
penetrated
only
O. 6 m m de e p w h i l e t h e lowes t
LET(22keY/p. m)
couldcompletely(38mm deep) pass through entire legs (5mm thick), the saturation level would be
due to either LET or dose-distribution orboth.
The damage saturation was also
observed for the skin reaction determinedby a scoring method.
When a counter
dose with 100keY/p. m of Carbon-12 wasde I i ve re d tot he i n' n er ski n i n add it ion tothe outer skin, the skin reaction in theouter skin was enhanced even though thecounter dose did not reach the outer skin(Fig.3).
These results indicated thatparticle beams
would beusefulfor
studying the volume effect of normal
tissue damage.

6 r-------------------~
I

60

I

>-

4JI

;

I

E

~3

1

-J>

1

-4°1
~
~

..

' + I

Q.)

.~

04

L

c

I

OJ

~ 30c

~ 20
Cf)

-.----r--;---:-~

o '20 40 ' 60 ' 80

I160

LET (keV/micrometer)
Fig.l Dependence of RBE for Skin
Shrinkag on Linear Energy Transfer.

penetration depth(0101)--e-39.S-=- 8.3

Skin Shrinkage (%)

1 -,+ - - r - - - r

U
Q.)

Cf)

-+-10 -"-30"0- 20 ~ 40

.~ 3

co

:§

.' ,
I

(j

Cf)

"

Q)

~ 1

~ 2]-

lOOkeV/micrometer). P,d' [

5

5°

-I

i 1

I

10

····2.8.. ··0.6

20 30 40

r

r

Cf)

--12 Gy

I

r
50 60

Fig.2 Volume Effect on Skin Shrinkage
after 135 Me V Carbon-12. Saturationof skin shrinkage is indicated by arrows.

-108-

c 2
~

DOSE (Gy)* N at I. Ins t. R a di 0 I . S ci .

0:"0- +collnter 24 Gy--- 24 Gr.-~- + cOI;nter 24 Gy

O'----------------.......Jo

5

10 15 20 25 30 35

Days after Irradiation
Fig.3 Enhacement of Skin Reaction
by Counter Dose of Carbon-12.

RIKEN Accel. Prog. Rep. 26 (992)111-4,;,9. Studies on Induced Mutations by Ion Beam in Plants
Induced Mutants of Rice Resistant to Bacterial Leaf Blight
H. Nakai, H. Watanabe,* Y. Kobayashi,* S. Kitayama, T. Takahashi, and T. Asai**

Bacterial leaf blight(BLB) of rice caused by
Xanthomonas campestris pv. oryzae is one of
the most important diseases seriously affecting
the production of rice in rice growing areas allover the world,l,2) M2 Plants (the second
generation after mutagen treatment) of rice
derived from the seeds irradiated by ion
beams(14N+), thermal neutrons and gammarays3) were inoculated by clipping the leaf tip

using scissors previously dipped in asuspension of 109-10 10 BLB cells/ml of isolate
T7133. The inoculated plants were scored for
disease severity by measuring the length of thelesions three weeks after the inoculation. The
resistant plants whose lesions we r esignificantly shorter than the control wereselected.

Table 1. Frequency of bacterial leaf blight resistant mutants of rice in the mutagens of ion beams,
thermal neutrons and gamma-rays.

Seed fertilityinM 1(%)~ seedlings*

No. ofPlants selected

Ion beam

1052

30,00025

8.3 X Ht4

Thermalneutron1.(}-1.5

53

30,00015

5.0 X 10- 430

49

15,00012

8.0 X 10- 4

Gamma-ray

No. ofFrequency ofresistant mutant

Dose(krad)

Mutagen* No. of seeds sown

The results are presented in Table 1. In thetable, frequency of the resistant mutants wascalculated as the number of resistant plants
selected per the number of total M2 seedlings
analyzed. It was noted that the frequency of
BLB resistant mutants by ion be a mbombardment was similar to that by gamma-ray
irradiation, and was higher than that by thennal
neutron treatment. Further screening tests for
BLB resistance in the later generations areneeded in order to obtain more precise data on
the mutagenic effect on the induction of BLB

resistant mutants. It can be concluded from thepresent experiment, however, that ion beams
could be one of the most effective mutagens for
induction of useful mutants for the plant
breeding.
References
1) H. Nakai et al.: J. Agric. Sci. Camb., 111,309(1988).
2) H. Nakai et al.:ibid., 114, 219 (1990).
3) H. Nakai et al.:RIKEN Accel. Prog. Rep., 25, 110(1991).

* Atomic Energy Res. Inst** Sizuoka Univ.
-109-

RIKEN Accel. Prog. Rep. 26 (1992)

111-4-10. Somatic Mutation Frequencies Induced by Ion
Irradiations in Soybean Strain L65 Heterozygous
at the Leaf Color Locus Y u
O. Yatou and T. Takahashi
Somatic mutation frequencies induced byion irradiations in soybean strain L65 wereobserved. The soybean strain has been
extensively used to detect the genetic effectof various mutagens.}) Plants of the strain
are heterozygotes of a mutant gene in a leaf
color locus YI I. Three types of somatic
mutation sectors, green sector, yellow
sector and yellow - green double sector, areobserved after mutagenic treatment.
Air dried soybean seeds were irradiatedwith Ar (88 MeVln, 0.06-8 Gy), N (136
MeV In, 0.06- 8 Gy) or gamma ray (0.1-1.6
Gy) of 60 Co. The ions were accelerated in
RIKEN Ring Cyclotron and the gammaray irradiation was conducted in theInstitute of Radiation Breeding. In each
irradiation, mutant sectors of 5 to 20
plants, i.e. 10 to 40 leaves, were observed.
Mutation frequencies induced by the threeradiations were shown in Figure 1, in
which numbers of the three types of sectors
were pooled. Unexpectedly gamma ray
induced the mutations at higher frequencies
than the higher LET radiations, Ar and N
ion beams. In the Ar irradiation, variationin number of sectors among irradiatedplants was extremely large, e.g. from 1 to
28 in a leaf (coefficient of variation = 0.92)
at 2 Gy. This indicates the possible effect ofshielding of the seeds, 7 mm diameter at
maximum, against the ion beam, because
the seeds were set in 2 to 3 layers. Then in
the following irradiation of N, the seeds
were placed in a single layer with theirem bryos at the beam direction. This
improved uniformity of the irradiation
effect, cv. = 0.59 at 2 Gy.
The numbers of yellow sectors werecompared with those of the other two typesof sectors (Table 1). Yellow sectors are
considered to be derived from, at higher.... 30

.;

-: 20

2o
~

~ 10

....

,.~
Irradiation (Gy)Fig. 1. Somatic mutation frequencies in YJ J locus
of soybean strain L65. The number of all three
types of mutant sectors was pooled in each
irradiations. The sectors induced by 4 Gy
irradiation of Ar were not counted because thenumber was too many.

Table 1. Relative frequency of yellow sectors inall sectors observed.
Yellow sectors
A

Others
B

AlB

N

573

60CO_ 7

1118

75
319

7.64
3.50

possibility, deletion or inactivation of thegene. l ) The relative frequency of yellow
sector was higher in the N ion irradiation
than in the gamma ray irradiation, whichsuggests that a single hit of the ion beam
has a lareger impact to the soybean
chromosome. A similar result was reported
in the thermal neutron irradiation in thissoybean strain. 2 )References
1) B.K.Vig:Mutation Res., 31, 49(1975).
2) T.Itoh, and S. Kondo:Jpn. J. of Genetics,-110-

66,461(1991).

RIKEN Accel. Prog. Rep. 26 (1992)

111-4-11. Effects of Heavy Ions on Fish Development
K. Ijiri, T. Takahash, M. Suzuki, S. Minohara, and T. Kanai
was calculated using the ratio. of the count o.f aparallel-plate avalanche counter(PPAC) to thatof the ionizing chamber. Twenty to forty
embryos were irradiated for each data point.
They were then placed in glass vessels withstored tap water to develo.p at 250 C.
Embryos were irradiated at different
developmental stages ranging from 0 to 3 days.
For Nand C io.n beams, various LET values
were realized, placing the Al absorbers along
the beam axis. Hatching percentage ofirradiated embryos was obtained as a functionof the dose at each LET value. 1,2)
When these data were compared with the

The effect o.f heavy io.ns o.n the develo.pmento.f the fish, Oryzias latipes was studied.
Fertilized eggs were collected after natural
spawning between the l-year-o.ld adult fish,
and were incubated at 25°C for further
develo.pment. Matui's normal table of thisspecies was employed for the identification of
the stages of their development.
Embryos were irradiated with the beams
accelerated by RIKEN Ring Cyclotron. C ions(135 MeV/nucleon), N ions (135 MeV/nucleon)
and Ar ions (95 Me V/ nucleon) were employed.
The beam dosimetry was carried out using an
ionizing chamber. Then, the flux of the beam

10.---------------------------------------------------------~

o 3

0

c

0
I;.

1

o Z

0

01

0
0
0

Z

1

C

1 Day

0

Z

C

Z Day

0

3

C

3 Day

N

o Day

1

I;.
I;.

o Day

0

Z
3

I;.

03
01;. 301
o Z 0 Z
1;.1
I;.

01

0 Z

I;.

1

N

1 Day

I;.

Z

N

Z Day

I;.

3

N

3 Day

At

o Day

0
o Z 0 3

03
01

o 3

03
03

0

1

At

1 Day

0

Z

At

ZDay

0

3

At

3 Day

t:. 3

t:. 1
t:. 3

LET (keV/ f1 m)
Fig.I. The relationship between LET and RBE for hatching of medaka (Oryzias latipes) embryos (Preliminary data).
Developmental stages of embryos irradiated are expressed as 0 (stage 11), 1 (stage 19), 2 (stage 24), and 3 (stage 26).

hatching percentage after the y-rays irradiation,
137Cs was used as a source of y-rays to obtain
the relative biological effectiveness (RBE).
Figure 1 summarises the relationship between
LEf and RBE so. far obtained for four different
developmental stages of embryos. With anincrease in LET, RBE alSo. becomes larger.
The lack of data points for LET larger than 100

keV/~m, is soon to be filled when irradiatio.ns
with Ne ions are carried out.

References
1) K. Ijiri, K Tao, K Nakano, M. Suzuki, and T. Takahashi:
RIKEN Accl. Prog. Rep., 25, 112 (1991).
2) K. Ijiri and T. Takahashi: BioI. Sci. Space, 5, 244-111-(1991).

5. Instrumentation

RIKEN Accel. Prog. Rep. 26 (1992)

111-5-1. Development of New Data Acquisition System
at RIKEN Ring Cyclotron Facility
N.Aoi, Y.Doki, Y.Watanabe, T.Ichihara, and A.Yoshida
We are now developing a data acquisition
system for CAMAC using a new SCSla) cra tecontroller 3929 developed by Kinetic System
Corporation. We will show results of the test andits usefulness in this report.
The present data acquisition system at RIKEN
Ring Cyclotron1 ) consists of a micro VAXIl(O.9MIPS) and Kinetic 3922/2922 crate controllers
connected by a Q22 bus. Recently, the perfonnanceof 'computers increased dramatically, and a fastand cheep computer, "workstation", appeared. On
the other hand, nuclear experiments become more
complicated nowadays and much faster computers
are needed.
But a workstation was not used for nuclear
experiments since it did not have a suitableinterface to CAMAC. The new crate controller
allows us to connect a CAMAC system to aworkstation through a SCSI because a SCSI isvery general and almost every workstation has it.
The bus length limitation of a SCSI (6m) can be
resolved by using a bus extender.
We measured the time requirement of CAMAC
functions using the new system under thefollowing condition as shown in the Fig. 1.

I B.UlCxl=cZr I
IiI"-~~~-"-"I"-"-"-:'!
VAX
Ii.[MJ cr£]:I• 30mfiber ...
• • • _ •• - •• _ •• -:- •• - •• _ •• _ •• - ••:Optic:a1: (up to IKm)

Workstatton System

Fig. 1. The setup of a test bench.

1. Crate Controller : Kinetic 3929

2. Computer: VAXstationb)
3. CAMAC module : CES2180c)
4. Bus extender: APPLIED CONCEPTS
Laser link wi th
a 30m optical fiber.
The results are shown in Table 1. The transfer
rates are somewhat slower than those of thepresent system but fast enough for mostapplications at the RIKEN Ring Cyclotron.
We also measured the time requirement ofasynchronous interrupt for VAXstation3100. It
takes 26ms which is about one order of magni tude
slower than the present system. We will study

Table 1. The transfer rate of CAMAC function.

single .........
transfer
block ............
transferread [words/sec]
writer words / sec]read [kwords/sec][blocks/ sec]

VAXsta tion4000-60
Direct'"Optical link ......
472
469
448
448
144
369
46
18

VAXstation31 00-76
DirectOptical link
370
338
370
338
125
281
34
16

Directly connected by a SCSI cable.
Connected through a 30m optical fiber .
Data transfer using a single CAMAC function.
..........
Data transfer by the block transfer (lblock=16kbytes)
We could not measure the Block transfer write because of its unstableness.
......
.........

further whether it results from the hardware or
the software. On the VAXstation4000, interrupt
does not work due to a known bug and will be fixedsoon.
We used this system in an actual experiment of
about Iblock transfer per secound. Then it was
confirmed that this system works well if theevent rate is not so high. In case of high-rate
experiments, we cannot tell whether this system

works or not at the present time.
Though this system still contains some problems
as we mentioned above, we succeeded in
introducing a powerful tool, "workstation", to theexperimental scene at the RIKEN Ring Cyclotron.
References
1) T.lchihara et al.:IEEE TRANS. ON NUCL. SCI.36-S,
1628(1989).

a) SCSI or Small Computer System Interface: Interface standard widely used for a peripheral device such asa disk drive or a magnetic tape.
b) VAXstation3100-76(7.6MIPS) and VAXstation4000-60(13MIPS)c) CES2180:CAMAC Auxiliary Crate Controller. It is generally used in RRC experiments as a front end buffer.

-113-

RIKEN Accel. Prog. Rep. 26 (1992)

111-5-2. Computing Environment around the Accelerator Facility
T. Ichihara, A. Yoshida, and Y. Watanabe
A general description of the data acquisition system at
the RIKEN accelerator research facility can be foundelsewhere}) In this report, we will describe the recent
improvement of the system.
(1) On-line data acquisition system
Currently, seven Micro VAX's are used for the on-line
experiments at the RIKEN accelerator research facility.
The node names and locations are as follows:
RIKMV1:: Micro VAX II (IF)RIKMV2:: Micro VAX II (B2F E3)RIKMV3:: Micro VAX II (Linac )RIKMV 4:: Micro V AX II (B2F RIPS)
SMART:: V AX Station 3520 (B2F SMART)SMARTF:: V AX Server 3300 (B2F SMART)RIKLV2:: VAX Station 3100 M76 (IF)Independent measurements and counter tests can be
performed without interference. The current version of
the data-taking program supports the CAMAC multicrate parallel-readout using multi-nl's (starbursts).
The throughput of the data acquisition is increased byusing these parallel readout features. Recently several
digital audio tape (DAT) units of 2 GB capacity havebeen installed for on-line data recording. Now a DAT is
the most standard recording media for the on-line
experimenl

available at the accelerator facility.
FACOM M-380(Ring cyclotron)
FACOM M-1800/20(Computer center)
These two computers are connected by the Netwrok
Job Entry (NJE) and DSLINK via the ethernet. These
two computers are also connected to the DECnet/SNA
Gateway.
Operation of the FACOM M-380 will be terminated in
the end of March 1993, because a recent RISC-based
computer is much more efficient and faster than the oldstyle main-frame computer.
(4) Wide area network
The RIKEN accelerator research facility is connectedto the world-wide network of HEPnet (High Energy
Physics NETwork) / SPAN (Space Physics Analysis
Network) as Area 40, which is a part of the DECnet
Internet, and the TISN internet (Todai International
Science Network) which is a part of "The Internet"(NSFnet, ESnet, NSI, DDN etc.).
In order to support these wide area network
connections, we are now supporting following 6 leasedlines at the accelerator research facility.
512 kbps
64 kbps
19.2 kbps
9.6 kbps
9.6 kbps
9.6 kbps(2) Off-line data processing system -I
The following VAX's are available for the off-line
data analysis and for general purposes.

to University of Tokyo
to RIKEN Tsukuba Center
to RIKEN Komagome
to KEK, Tsukuba
to Tokyo Institute of Technology
to NIT X.25 (DDX-80)

The link to University of Tokyo was upgraded from
64 kbps to 512 kbps in June 1992 using the opticalfiber. The leased line between RIKEN-Wako and
RIKEN -Tsukuba was also upgraded from 9.6 kbps to64 kbps in February 1992.

RIKEN:: (virtual node name of the cluster)RIKV AX:: VAX-6610 (Central)RIKVSO:: VAX Station 4000-60
RIKVS2:: VAX Station 4000-60
RIKVS3:: VAX Station 4000-60
RIK835:: VAX Station 4000-60
RIKLV1:: VAX Station 3100 M76
RIKSNA:: DECnet/SNA Gateway
Theses computers are connected by LA VC (Local
Area VAX Clusters) via the ethernet. They are also
connected to the HEPnet(DECnet) and TISN Internet(DECnet/IP) and reachable from allover the world.
Since the load of the VAX-6510 was too heavy, we
have upgraded the VAX-6510 to VAX-6610 in May
1992. By this upgrade, the performance of RIKVAX::
has been increased about a factor of 3 (from 12 VUPS
to 32 VUPS).

(5)Address of the electric-mailThe address of the electric-mail for general user of the
RIKEN accelerator research facility is described asfollows, where the userid should be replaced by a proper
name.
(HEPnet/DECnet)
RlKEN::USERID (or 41910::USERID)(Internet/Bitnet)
USERID@RIKVAX .RIKEN.GO.JP

References(3) Off-line data processing system -2
Following FACOM main-frame computers are- 114-

1) T. Ichihara et al.: IEEE Transaction on
Nuclear Science, 36-5 p. 1628 (1989).

RIKEN Accel. Prog. Rep. 26 (1992)

111-5-3. High-Resolution Dispersive-Mode Beam Transport to theSpectrograph SMART
T. Ichihara, Y. Fuchi, K. Hatanaka, H. Kawashima, S. Kubono,S. Miyamoto, T. Niizeki, -.S. Takaku, M.H. Tanaka, T. Yamamoto, and H.Ohnuma
High-resolution dispersive-mode beam transport to the spectrograph SMART has beendeveloped. Since the momentum spread of theaccelerated beams from the RIKEN Ring
Cyclotron is estimated to be about 0.05%, thehigh resolution dispersive-mode beam transport
is required for high-resolution experiments
using the spectrograph SMART.

In this case, the beam matrix on a counter ofthe second focal plane of the spectrographbecomes as follows.
-0.288 0.009
0.000 0 . 000
0.000 0.000-10.023 -3.119
0.000 0.000 -0.838 O. 064
0.000 0.000 - 15.175 -0.032
5.095 -0.175
0.000 0.000
0.000 0.000
0.000 0.000(1) High-Resolution Beam Transport

0.000 -0.000
0.000 176.531
0.000
0.000
0.000
0.000
1.000 90.116
0.000
1.000

The matrix element of MI6 (dispersion) at thecounter is 0, thus the dispersion matching being
achieved.

This transport has a horizontal focus pointwith large dispersion (13m), where the beam
can be cut by the slit in the wall (A 11). The
transport matrix of the beam at this focal point
is written as follows,·(E~dIl7A.d)E'" OlSpor$l .... M0DE TR ..... NSP0RT (lOQ;2.10.71 so 2.17 5 m'

BEAM ENVEL0PE
X-1.0SMM. OX - 2.0DMR.

Y-I .5 0MM. Y-

I. I JMR. OP - O.O~!(Iu;-1.199 0.000 0.000 0.000-3.783 -0.833 0.000 0.000
0.000 0.000 -0.239 -0.276
0.000 0.000 1.975 -1.894-1.151 -1.098 0.000 0.000
0.000 0.000 0.000 0.000

0.000 13.179
0.000 31.961
0.000 0.000
0.000 0.000
1.000 11.430
0.000 1.000ci

where the notation of the beam matrix follows
the program TRANSPORT.
The momentum resolution at this focal pointis estimated as P/M'=11,000, assuming that thebeam is cut by a horizontal slit of Imm width.
(2) Disparsive-Mode Beam Transport
Fig.I. Typical beam envelope of this transport.

The dispersion of the beam spot on a target ofthe spectrograph SMART can be adjusted bychanging some quadrupole magnets in the beamtransport system to archive the dispersion
matching of the beam transport and thespectrograph. This is necessary for light-ion
beams because the slit cannot be used for theintermediate energy light-ion beams. For
example, in a typical measurement of the 0
degree change-exchange reaction, the beam
matrix on the target is set to be as follows.
-0.540 0.018 OrOOO 0.000 0.000 14.247
0.000 -1.851 0.000 0.000 0.000 -26.242
0.000 0.000 -0 . 760 0.000 0.000
0.000
0.000 0.000 -2.247 -1.315 0.000
0.000-1.416 -2.589 0.000 0.000 1.000 23.049
0.000 0.000 0.000 0.000 0.000
1.000

-

-

Figure 1 shows the typical beam envelope of
this beam transport.
So far, we have achieved the momentum
resolution of P/.1P=5,000 using the spectrograph SMART. A typical example of thespectra of the 12C(12C,12N)12B reaction at
E/A=135 MeV obtained by the spectrograph
SMART can be found elsewhere in thisvolume. I) In this case, the overall energy
resolution was 700 keV(FWHM) using a 1.62
GeV I2C beam. We are expecting to obtain atwice better resolution in the near future by
im proving the beam transport and the methodof tuning the disperssion matching.
References
1) T. Ichihara etlal.: This re~rts, p. '17...

-115 -

RIKEN Accel. Prog. Rep. 26 (1992)

111-5-4. A Proportional Scintillation Imaging Chamber for
Heavy Ion Detection
M. Suzuki, T. Takahashi, and K.Kuwahara
In understanding the overall effect of heavy ion irradiation on biological systems, it is essential to determine
the spatial distribution of the deposited energy along ionization tracks. In this respect a proportional scintillation
imaging chamber (PSIC) represents an ideal instrument,
since it can visualize the spatial distribution of the secondary electrons in the ionization tracks produced byheavy ions in the chamber gas. 1) In this report we describe a prototype PSIC constructed, and report the observed optical images of the ionization tracks of N ions
(135MeV/nucleon) and of Ar ions (95MeV/nucleon)
both accelerated by the RUffiN Ring Cyclotron.
As shown in Fig. 1, the prototype consists of a drift
chamber and a parallel plate avalanche chamber (PPAC),
each section being separated by stainless steel meshes.
The chamber gas used is a gaseous mixture of argon(88%) + methane (10%) + triethelamine (2%). Entering

the drift chamber through an entrance window made of astainless steel with a thickness of 200J.lm, heavy ionsgenerate the secondary electrons along their paths. Theseelectrons will drift towards the PPAC under the influenceof an applied electric field. Passing through the firstmesh, the electrons initiate electron avalanches due to thehigh electric field in the PPAC. The luminescence associated with the electron avalanches is observed with animage intensifier coupled with a CCO camera, focusedon the second mesh in the PP AC. Since the luminescence induced is highly localized at the site of the electron avalanches, the luminous pattern observed will be
the projection image of the secondary electrons generated
by the incident heavy ion. The optical images detected
are monitored on a TV screen, and are recorded on a video
tape. The video signals are digitized and processed with acomputer for further analysis and storage.

Heavy Ion
Beam PortAnodeUV Object Lens
UV Window

H V
Field
Shaping

Ring

Ceramics
SpacerFig. 1. Cross sectional view of the proportional scintillation imaging chamber and its associated opticalreadout system.
The observed ionization track images produced by a N
ion of 135Me V/nucleon and by an Ar ion of
95MeV/nucleon are shown in Fig.2 and 3, respectively,
together with the variations of the relative brightness
perpendicular to the tracks. The real size of each pictureis 71 mm x 95 mm. The brightness curve indicating
the electron density has a peak at the center of the ionization track, and decreases on both sides symmetrically.
It can be also seen that the peak appearing in the Ar ion
track is sharper than that in the N ion track, and that the- 116 -

Ar ion track is not tailing as long as the N ion does.
The values of dE/dx for the Ar ion and for the N ion canbe estimated to be 2.5 (MeV.cm 2/mg in water) and 0.29
(MeV.cm 2/mg in water), and the maximum range of the
a-rays to be 23 (cm) ~d 45 (cm) in the present chambergas, respectively. 2) It is, therefore, expected that thesecondary electrons in the ionization track are more localized near the central part in the Ar track than in the N
track, being consistent with the present results.

·:
II

(a)
(a)

..

'~

-.~

100

(b)

90

30----------------------------~

80

N ion (135MeV/n)

70
!':i

(b)

25

I~

60

·~·c

Ar ion (95MeVln)~ ;. 50c ..

-'":c .~ 40,~-e...:I.e30.J \.~

20
10

~~

1

51

~

101 151 201 251 301 351 401 451 501 551 601

51~------~

101 151 201251 301 351 401 451 501 551 601

Trans\'ersal position (pixel number)

Transversal Position (pixel number)

Fig. 2. (a) Photograph of the ionization track produced
by a N ion (135MeV/nucleon) and (b) the transversal
brightness variation of the track image.

Fig. 3. (a) Photograph of the ionization track produced
by an Ar ion (95MeV/nucleon) and (b) the transversal
brightness variation of the track image.

References,
1) M.Suzuki and T.Takahashi: in Proceedings of2)

International Conference on Evolution in Beam Application. p.397, November 5-8,1991, TakaSaki,-117-

Japan.
M.P.R.Waligorski, R.N.Hamm, and R.Katz: Nuc1.
Tracks Radiat. Meas., II, 309(1986).

RIKEN Accel. Prog. Rep. 26 (1992)

111-5-5. Heavy-Ion Radiation Damage on Position-Sensitive
Silicon Detector
M. Kurokawa, T. Motobayashi, T. Nomura, K. Morita, and A. Yoshida
An ion-implanted position-sensitive detector was
designed and fabricated 1) for the experiment ofsuperheavy element search. 2) During the experiment it
is exposed in the radiation environment of heavycharged particles (A>200). We studied the effect ofradiation damage induced by 110Xe ions at 53 MeV.
The radiation damage for heavy charged particles has notbeen well studied so far as compared with that for lightparticles like proton and neutron.
The 110Xe ion was produced by the fusion reaction
58Ni( 58Ni,a2n)110Xe and transported by the gas-filled
recoil separator (GARIS) at RIKEN. The resultant
damage factors for 110Xe are listed in Table 1 together
with those for protons and 28Si 3 ). The first row
corresponds to the damage factor a(A/cm), which isoften used for expressing the degree of damage. It is
used to,dJ
a=d<J>k=-dD

Damageparticleenergya (nA/cm)kref.

proton21 MeV

2.7x10- 7

8.7x10- 8[4]

proton25 MeV

2.2x10-7

8.1 x10- 8[5]proton65 MeV

1.1xlO- 7

8.6x10- 8[6]

proton12 GeV

3.0x10- 8

1.0x10- 7[7]

proton800 GeV

2.9x10- 8

7.6x10- 8

[8]

28Si

80 MeV

3.2x10- 4

1.6x10- 7

[3]

llOXe

53 MeV

5.6x10- 3

1.9x10- 6

present(1)

where J(A/cm 3) and <l>(cm- 2) are the leakage current
density and the irradiated fluence, respectively. The
significant difference of the order of about 4 is seen
between the damage factors a. for protons and heavyions. This might be partly due to the difference in the
total energy deposit to the detector. To take this into
account, the fluence <l> is replaced by the doze D(J/Kg),
and a new damage factor k is defined as,

dJ

Table 1.

(2)

As seen in the table, the k values for protons arealmost constant despite of the huge difference in theincident energy. This suggests that the damage isdetermined by the amount of the irradiated dose.
However, those for heavy charged particles are stilllarger than for protons. The damage reflets the numberof the defects made by the nuclear collision or the
non-ionizing energy loss of incident particles withsilicon, whereas the most part of energy deposit is dueto the ionization process. The constant k value meansthat the ratio of energy loss by nuclear collision to thatby ionization is almost constant. The larger k values
for heavy ions may be explained by the increase of thenuclear collision contribution at very low velocity
region, where the ionization process is suppressed byfactorsforvariousincidentions.

the decrease of the effective charge of ions. Notethat the velocities are very low for the 28Si and llOXe
listed in Table 1, whereas those of the protons arehigher enough to be free from the effective charge effect.
References
1) M. Kurokawa et a/.: RIKEN Accel Prog. Rep., 2S, 120(1991).
2) T. Nomura et al.: RIKEN Accel Prog. Rep., 24, 25(1990).
3) N. Kato: Nucl. Inst. and Meth.,BSl, 425(1990).
4) G. Lindstrom et al.: Silicon Detector for Calorimetry Developmentsfor HI at HERA - V International
Conference on Instrumentation for Colliding Beam
Physics, Novosibrisk, March 1990.
5) G. Lindstrom et al.: DESY Report 89(August, 1989).
6) M.Kubota et al.: Conference Record of the 1991 IEEE
Nuclear Science Symposioum and Medical Imaging
Conference November 2-9, 1991 Santa Fe, New Mexico
USA,vol. I, 1246.
7) T. Ohsugi et al.: Nucl. Inst. and Meth. t A26S, 105(1988).
8) N. Nakagawa et al.: Nucl. Inst. and Meth.,A270, 421(1988).

-118-

RIKEN Accel. Prog. Rep. 26 (1992)

111-5-6. Straggling of High Energy Heavy Ions in
Silicon Detectors
K. Nagata, T. Doke, K. Itsumi. T. Shino, T. Kashiwagi, J. Kikuchi,
N. Hasebe, H. Moriya, A. Nakamoto, T. Yanagimachi, H. Murakami,
S. Sugino*, and T. Kohno
The energy loss straggling in silicondetectors for high energy heavy ions arecompared with the theoretical gaussian
dis t rib uti 0 n . 1 ,2)The enegy loss
distributions are measured in si I icon
detectorsof
0.515- 3.130 mm inthickness for 135 MeV/u 12C, 135 MeV/u
14N, 100 MeV/u 180, and 95 MeV/u 40Ar
nuclei.
An
experimental
energyloss
distribution for 95 MeV /u 40 Ar in 1.848
mm . thick silicondetector is shown in
Fig.I.
A solid curve shows theexperimental distribution,
and a chain
curve shows the theoretical gaussian
distibution.
The experimental depositedenergy loss 908.6 MeV is 3.6% lower thanthe calculated value of 939.3 MeV,andthe distribution width (FWHM) is greaterthan the theoretical width.
Ar~O

The ratio of thewidth obtained
experimentally to the width from Bohr's
theory is plotted in Fig.2 as a function of
the ratio of fractional energy loss to theincident particle kinetic energy.
A solidcurve shows
the ratiosof the Payne's
theoretical
widths 3 ) forvery large
energy losses to the Bohr's theoretical
widths
The result shows that themeasured distribution widths are inagreement with the theoretical widths
when the ratioof the fractional energy
loss to the particle kinetic energy is lessthan about 20%.
And the experimental
widths become to be too wide for theenergy losses over 20% in comparison
with the theoretical Payne's widths.
12
6

~

C

a 14N

95MeV/n 1848.3um

aOO_-----'ir----,.---,..----__--~

AE/E. ~ 23.9 %

Bohr

.,

~

600

c::
c::
o

o~--~~~~~~~~~----~~~

0.1

FWHM

:J

I

10

100

Fig.2.
The
ratio
of
the
experimental
distribution width (FWHM) to the theoreticalgaussian width (FWHM) as a function of theratio of thefractional energy loss to theparticle kinetic energy.
Solid curve is theratio of the Payne's distribution widths to thegaussian distribution widths.

III<3 200i -"'.'---_._._--~-

AE/E. (81,)

t3 400

"-c::

_0_

AE

700

aoo

900

1000

Energy(MeV)

References
Fig. 1.
Experimantal energy loss distribution
for 95 Me V /u 40 Ar in a 1.848 mm
silicondetector. A chain curve shows the theoreticalgaussian distribution.

1) K. Nagata et al.: RIKEN Aceel. Prog. Rep.,
24, 115 (1990).
2) K. Nagata et al.: ibid., 25, 132(1991).
3) M . G. Payne: Phys. Rev., 185, 611(1969).

* Rikkyo Univ.
-119 -

RIKEN Accel. Prog. Rep. 26 (1992)

111-5-7. Calibration Experiments for the Identification of Isotopes

by Telescopes HEP-MIs aboard the Geotail Satellite
N. Hasebe, H. Moriya, K. Fujiki, T. Kashiwagi, J. Kikuchi, T. Doke, T. Haya.shi,
K. Itsumi, T. Shino, T. Ito, K. Nagata, A. Nakamoto, H. Murakami,
T. Yanagimachi, S. Sugino, *and T. Kohno
The science satellite Geotail was launched forthe research in the tail of the earthmagnetosphere in July, 1992. Medium energy
Isotope telescopes, HEP-MIs, were installedon the Geotail for the purpose of observing
the elemental and isotopic composition ofcosmic rays. 1) The telescopes include several
silicon detectors to measure heavy particles of
2 ~ Z :$; 28 in the energy range 2.2 to 110
MeV/n using a well-known L\ExE method. A
cross sectional view of the MI2 is shown in
the inset of Fig.l. The telescopes consist of 6
silicon detectors which are 2 two-dimensional
position sensitive detectors 2 ) (PSD 1 and
PSD2) and 4 L\E-detectors (DI-D4).
The calibration experiment for the MI2s was
carried out at the RIKEN Ring Cyclotron
accelerator facility. Good Si detectors wereselected in advance for the experiment. 0 and
Ar beams wi th energies of 100 MeVIn and 95
MeV/n, respectively, were used to measure
the fundamental characteristics of the telescopes. The fragmented beam produced by the
nuclear reaction of the oxygen beam with atarget of an acrylic plate was irradiated at theincident angle of 0 0 to the MI2 telescopes.
Figure 1 shows a scatter plot of energy loss
L\E versus total energy E for the fragmented
particles stopped in the D3 detector, where
AE and E represent the sum of the energy
losses Dl(O.2mm) and D2(0.4mm), and thesum from Dl to D3(2.0mm), respectively. As
seen from the figure, isotopes from Li to N
are clearly resolved.
Figure 2 shows mass histograms of Be, B,
C and N. Excellent mass resolutions, better
than O.37amu expressed in fwhm for isotopes
from Li to N, have been achieved for the
HEP-MI telescopes.
It is found from the beam experiments usingo and Ar ions that isotopes heavier thancarbon are clearly resolved by the MI telescopes.

*

8

I t - ---e- PSD- 1

C""I

~

PSD-2

01
02
03

o~

04

______________________oTotal Energy ( MeV)~

800

Fig. 1. Total energy E vs. energy loss AE scatter plot
obtained from the fragmented beam produced by 100
MeV/n oxygen.

NC

12 13 14 15 16 17

11 12 13 14 15 16

BBemass number

9

10 11 12 13 14

mass number

mass number

7

8 9

10 11 12

mass number

Fig. 2. Mass histgrams of Be, B, C and N isotopes.

References

Faculty of Science, Rikkyo Uulv.

-120-1) T. Doke et al. : IS AS, SP, No. 10 (1989).
2) N. Hasebe et al. : JJAP., 31, 1191, (1992).

RIKEN Accel. Prog. Rep. 26 (1992)

111-5-8. Detection of Scintillation Photons in Liquid Xe from Heavy Ions
and Their Attenuation Length
T. Doke, S. Ben, A. Hitachi, N. Ishida, K. Ito, M. Kase, K. Masuda,
Y. Qu, M.Suzuki, and T. Takahashi
Liquid xenon (LXe) is a good scintillator forradiation detection and will be possibly usedin nuclear and particle physics in J?ear future.
The critical factors for detection of LXescintillation photons are the reflection of thescintillation light (170 run) on walls and theattenuation length of the light in the liquid.
Last year we measured the dependence ofthe light intensity on the distance between theincident position of heavy ions and thephotodiode as a photon detector. An effective
attenuation length of about 10 cm was
obtained for the scintillation in LXe by using
several kinds of reflector walls for VUVphotons. I)
This value of the effective
attenuation length includes the geometricfactor (solid angle), the reflectivity of themirrors and the light attenuation length of the
LXe itself. In the present experiment, black"ralls with no reflection are used to clarify
which factor is dominant in this effective
attenuation length.
The apparatus is the double vacuum chamber\vhich is the same as that used previously. 1)
The effective length of the chamber is 65 em.
The chamber has seven beam windows which
are separated by 10 em from the neighbors
along its length. A photon detector is a silicon
photodiode or a vacuum triode. The liquidvolume is surrounded by black walls which
are made of almite.
The incident ions entered and stopped in LXeafter passing through a Mylar window of thebeam line, about 10 em air, and then thechamber windo"'s (40 J-lm Havar and 200 mm
SUS). A thin (100 J-lm) plastic scintillator was
sometimes used to obtain a beam trigger. The
ions used were 135 MeV/n N, 100 MeV/n 0

and 95 MeV/n Ar from the RIKEN Ring
Cyclotron.
Xe gas was purified by passing through an
Oxisorb purifier and molecular sieves (4A)
with a flo,,' rate of 5 l/min and then liquefied
in the chamber. The LXe temperature was
kept at -7S'C with dry ice.
Charge signals from the photodiode or thetriode were processed with a preamplifier, ashaping amplifier (peaking time of 1J-ls) andanADC.
The obtained effective attenuation length isabout 9 cm for all cases of incident ions andphoton detectors. This value is very close tothat obtained with reflection mirrors inside thechamber. Namely this fact means that thereflection mirrors do not work well for VUVphotons of the wavelength of 175 nm asconsidered previously.
In order to confirm the intrinsic attenuation
length of the VUV photons in LXe itself, we
measured photon yields due to alpha particles
in LXe as a function of the distance between
the source 2 the photomultiplier in a small
test chamber. An intrinsic attenuation lengthof abou t 3 meters is obtained. This has
confinned the above results for heavy ions.
For good unifonnity of scintillation response
as a high energy calorimeter, development ofgood mirrors in LXe is necessary.

ang

References
1) T. Dokeet a1.: RIKEN Aceel. Prog.Rep.,
25, 140 (1991).
2) N.Ishida et a1.: Proc. Int. Conf. on Liquid
Radiation Detectors, p.353, April (1992),
Tokyo, Japan; N. Ishida et a1.: Nuel.
Instr. and MetlL~to be published.

-121-

RIKEN Accel. Prog . Rep . 26 (1992)

111-5-9. Isotope Separation of a Cosmic Ray Telescope
C. Kato, T. Kohno, T. Imai, H. Kato, and K. Munakata
We have developed a cosmic ray Heavy Ion
Telescope (HIT) with a very large geometricfactor of 30 cm 2 . sr. The HIT is going to belaunched into a geosynchronous orbit in 1994. The
brief description of the telescope is given
elsewhere . 1 ) In addition to the numericalsimulation,2) the ground calibrations of thetelescope using heavy ion beams of an accelerator
are a very important and indispensable procedure
for confirmation of the instrument abl1ity and thereliability of the obtained data in space.
We used a beam of 160 with an energy of 135
MeV Inucleon for a ground calibration experimentof a flight model of the telescope. The beam willstop in the telescope. The obtained mass
resolution for the incident 16 0 is reported in aprevious report. 3 ) Since we have no magnetic
analyzer at our beam port, we did not use any
target for fragmentation production. Therefore
we considered that the mass resolution
measurement for only 160 was possible with thisexperimental set up. But we found a different
situation in the obtained data. We used acollimator to determine the characteristics ofPosition Sensitive Detectors (PSD).
..

""
•

:>
OJ
::E:
L.L.I
I

n::l
+-l

o
o

~

VI

+-l
t::
~

o

0

0
N

U

o

8

10

12

14

Mass
,~..: 9. ,
~ '."

0

(62 mm x 62 mm), we strongly defocused the beamusing Q-magnets. As a result it is conceivablethat the beam lines were bent from a pureparallel beam line. Therefore some parts of thisbent beam could passed through the hole bygrazing the edge of the narrow hole of 1 mm <p x 6
mm length. By this effet t, a part of the
col1linator could be a target and some secondary
fragments were produced in the beam. Fig.I.
shows a continuous energy loss of 160 itself andthe existence of lighter nuclides produced by
nuclear fragmentation.

Fig. 2. Mass histogram for an element of carbon.

.

. "'::':"-:'.~ .

aA histogram example of isotopic separation for
carbon is shown in Fig.2. The obtained mass
resolution is about 0.4 amu in FWHM. This value
is much better than 0.6 amu which was obtainedfor 16 0.3) This comes from the low noisecharacteristics of the PIN-type detector used forthis analysis in contrast with the relatively
large noise existence for the Si(Li) type detector
in which 16 0 stops because of their large
thickness.

C\2

a
0

~

Q.J

Cl

100

200

Residual-E (MeV)
Fig. 1. Scatter plots for two detectors named PIN2 andPIN3 for events stopped in PIN3.

This collimator made of a 6 mm thick brass
plate had 1 mm <p holes on the 13 x 13 lattice
points at 5 mm intervals. In order to get a wide
beam profile to cover the large area of the PSDs

-122-

References
1) T.Kohno: Space Sci. Rev., 51, 185 (1989).
2) K.Munakata et a1.: Nucl. Instrm. Methods, A276,
306 (1989).
3) T.Kohno et al.: RIKEN Accel. Prog. Rep., 25, 134(1991).

RIKEN Accel. Prog. Rep. 26 (1992)

III -5-10. Collinear Laser Spectroscopy with Ion-Guide Beam
M. Wakasugi, T. Horiguchi, T.T. Inamura, T. Ishizuka, W.G. Jin,
H. Katsuragawa, M. Koizumi, S. Matsuki, K. Morita, T. Murayama, I. Nakamura,
K. Shimomura, T. Shinozuka, I. Sugai, Y. Tagishi, M. Takami, and A. Yoshida
Collinear laser spectroscopy has beensuccessfully made for many radioactive isotopes
but not for refractory elements. 1) Nuclear spins,
electromagnetic moments and mean square nuclear
charge radii can be investigated systematicallyover a long isotopic chain with this technique.
We are going to make the collinear laser
spectroscopy experiment for refractory elementswith a ion-guide beams from RIKEN-IGISOL.
Here we report the test experiment off-line. The
possibility of the experiment has been shown in
our previous work. 2)
To make preparatory collinear laser
spectroscopy off-line, we constructed a laserablation ion source for IGISOL using a Nd:YAG
laser. With this ion source, we extracted ions ofstable Hf and Ba isotopes, and tested ourcollinear laser spectroscopy system with Ba ion
beam. From this experiments the extraction
efficiency and the extraction time of IGISOL were
measured, and the efficiency of the photon
detection system was obtained.
The Nd:YAG laser beam was focused on ametallic target which was placed inside the
IGISOL gas cell filled with a helium gas. The ion
current produced by the laser ablation amounted
to IJ.1A in the gas cell and 1-2 % of the current was
extracted from an exit hole of the gas cell. The
yield of ions produced in the gas cell and theextraction efficiency strongly depend on thehelium gas pressure. Although it may depends onthe geometry of the gas cell, the most efficientgas pressure has been found to be 40 mb in thisexperiment. Because the Nd:YAG laser is a highpower pulse laser with the pulse width of 10 ns
and the repetition rate of 10 Hz, we could measure
the time profile of the extracted ion-guide beam.
In the case of the helium gas pressure of 40 mb,

the measured time profile of the pulsed ion beam
has an averaged deley time of 13 ms, the titrl~
width of 11 ms and decay time of 9 ms. These
values gradually increase as the helium gas
pressure increases.
The extracted ion beams were accelerated up to
60 keY and mass-separated with an analysing
magnet. The highest mass resolving power of 470
and 370 was also obtained at the gas pressure of 40
mb for Ba and Hf, respectively.
The separated ion beam was crossed with alaser beam collinearly and detected by aresonance fluorescence method. We measured
isotope shifts of the 614 nm transition for seven
Ba isotopes. This is the first time measurement of
optical isotope shift with the ion-gude beam. In
the fluorescence spectrum, the line width was 350
MHz, and it corresponds to an energy spread of ion
beam of 90 eV. This value is enough for theisotope shift measurement hut not for thehyperfine structure measurement. We can expect
the line width to be reduced by using a focusingdevise such as a SQUEEZER.2)
The fluorescence spectrum for 132Ba, which has
the smallest abundance of 0.101 %, was also
clearly observed with the ion beam current of 0.2
pA. From this measurement, the estimatedphoton detection efficiency was 10-5. This value is
not sufficient to make this kind of experimentwith radioactive isotopes. We are now improving
the detection system.

References
1) E.W. Otten: Treaties on Heavy-Ion Science, Vol. 8,

ed. by D.A. Bromley, Plenum Pub. Co., New York,(1989).
2) M. Koizumi et al.: Nuc1. Instr. and Meth., A313, 1(1992).

-123-

RIKEN Accel. Prog. Rep. 26 (1992)

111-5-11. Atomic Beam Magnetic Resonance Apparatus for Systematic

Measurement of Hyperfine Structure Anomalies(Bohr-Weisskopf effect)
H. T. Duong,"1 C. Ekstrom,*2 M. Gustafsson,*3 T. T. Inamura, P. Juncar,*4
P. Lievens,"s I. Lindgren,*3 S. Matsuki, T. Murayama, R. Neugart,*6 T. Nilsson,"3T. Nomura, M.Pellarin,*7 S. Penselin,"S J. Persson,*3 J. Pinard,..1 I. Ragnarsson,*9
O. Redi,*l0 H. H. Stroke,*10 J. L. Vialle,*7 and the ISOLDE Collaboration
The Bohr-Weisskopf effect, or hfs anomaly,
which results from the effect of the distributionof nuclear magnetization on the atomic electronnuclear interaction, will be studied
systematically, first for a long chain ofradioactive cesium isotopes, analogously to
isotope shifts, at the CERN PS Booster ISOLDE.
Results are expected to provide an independent
test for nuclear wave functions. Precision
measurelnents of the hfs splitting and nuclear. magnetic monlents are required, with sensitivity
adequate for the radioactive isotopes produced.
We have constructed at Orsay in France a triple
resonance atomic beam magnetic resonanceapparatus with optical pumping state selection.
Detection of the beam is by laser induced
fluorescence or mass spectrometry. The
performance of the apparatus was tested withstable K and Rb beams. Results obtained for gvalues and hfs anonlalies are in excellent
agreement with published data, and show thetechnique to be suitable for the on-line
experiments at ISOLDE. A precision better than
10-4 for g-value has been obtained in the tests,
leading to hfs anomaly measurements better than
10 percent. Details of the system will be described
elsewhere. 1 )The apparatus has been installed at the
ISOLDE facility and is presently being tuned up
for the on-line measurements of a sequence ofradioactive cesium isotopes.

RF~~PA NIAAFLUORESCENCE
DETECTION

RF~~:S~y LOOPB

mJ "\'12~ fr/~i'; ,.,..m,n.,.llT-r~'"

ION .. ATOMCONVERTER.. :: 'lEE: :. :.-:.
ISOlDEMJ""2/'NIZER=-Ii2JVzzZz721r:zJ IZ/zzizj -BEAM': MAGNET
.
A
LASER

BEAM

MAGNETC

MAGNETB

SIX POlEMAGNET

ELECTRON
MULTIPLIER

lASER

BEAM

MASS
SPECTROMETER

Fig. 1. Schematic of the experimental setup of ABMR
at ISOLDE.

Part of this collaboration is supported by the
Yamada Science Foundation, the Ministry of
Education, Science and Culture in Japan, the U.S.
National Science Foundation, the Swedish
Natural Science Research Council and theC.N .R.S. in France.
References
1) H. T. Duong et al.: Nucl. 171str. Methods A, in press .

.. 1 Laboratoire Aime Cotton, CNRS II.. 2 The Svedberg Laboratory, Uppsala Univ .
..3 Dept. Physi. Chalmers Univ.
>t4 Inst. Nat!. Metrologie du CNAM..5 CERN

ot6 Inst. Physik, Univ. Mianz..7 Laboratoire de Spectrometrie Ionique et Moleculaire,

Univ. Lyon I..8 Inst. Angewandte PhYSik, Univ. Bonn..9 Dept. Mathemat. Phys., Lund Inst. Technology..10 Dept. Phys., New York Univ.

-124-

RIKEN Accel. Prog. Rep. 26 (1992)

111-5-12. High Resolution PIXE Using Imaging Plate
J. Kawai and K. Maeda
An imaging plate (IP) is composed of aflexible plastic plate coated withphotostimulable phosphor crystal powder(BaFBr:Eu 2+).1) PIXE (particle induced x-ray
emission) is one of the trace and micro-analysis
methods of elements without troublesome
sample preparations. For the purpose ofelemental analysis, an energy dispersive
spectrometer (EDS) is used. On the other
hand, if a high resolution x-ray spectrometersuch as a wavelength dispersive spectrometer(WDS) is used, then chemical specifications ofelements in the compounds are also possible as
was first demonstrated by Kamada et al. 2) We
have tried to use an IP for an x-ray detector of
the Bragg type PIXE spectrometer tocompensate the weak analyte signal due to thetrace or micro-analysis, or due to the shortmeasuring time.

absorption edge (5.2 keY) is just below the Cr
K-L energy (5.4 keY). Therefore the detection
efficiency was higher for transition metals thanfor other elements. The IP used was Fuji Film
Type BAS-III IP.
Six-fold spectral
measurement was made by changing theirradiation time (1 sec"" 6 hours) as well as the ·Ar6+ current (0.1 ,.., 100 nA). Consequently,
the total sample currents were 0.01, 0.1, 1,
100, 500, 1800 f.1C for six measurements in alimited beam time of the linear accelerator.
After the exposure of x rays, the x-ray intensity
was read by a Bioimaging Analyzer FUJI
FILM BAS 2000 as shown in Fig.2.
X-ray energy / eV
6400
6500
6600
18¥---------______--------~------------~----~

..J

en
Q.

IP

_ 10

~

0)

·s
~-..

ecn

I~

C

-..,s
u

CD

11Slitso+-~--~~--~o__--____--__

~

100

160
PIXEL number / 0.1 mm
Fig. 2. Plot of Fe KLn_Ln+ 1 spectrum digitized fromthe IP image of a width of 1.5 mm. The total
beam current was 1800 J..lC.

II
Fig. 1. Schematic drawing of the experimental setup.
The slits were 0.3 mm wide. Practically, the IP
was wrapped by an aluminium foil. The analyzing
crystal was LiF(220).

X-ray emission measurements were
perfonned at the RIKEN Linear Accelerator(RILAC). The setup of the experiment isshown in Fig.1. The x-rays were induced by
42.2 MeV Af6+ ions projected on a steel AISI
430 (Fe 81.4 % and Cr 17.1 %). The reason
we chose this steel was that the Ba L3

The multivacancy satellite intensity
distribution is expressed by a binomial law
I(KLn) = 8Cn PL n (1 - PL)8-n, where PL is theionization probability from L shell, and n thenumber of the L shell vacancy. 3) We analyzed
the spectrum in Fig.2, and obtained PL=0.27.
Folkmann4) reported that PL=0.33 and 0.22 for
Cr when excited by 1.4 MeV/u C18+ and ()4+,
respectively. Our value (0.27 of Fe excited by
1.1 MeV/u Af6+) is quite reasonable comparedwith those of Folkmann.
To get a sufficient spectral intensity in thepresent experimental condition, the total beam-125-

current was enough for 500 flC, which wasachieved by irradiation of less than 1.5 hours
when the beam current was 100 nA. Thismeans a rapid measurement is possible whenthe IP is used.
In conclusion, we have fIrst demonstrated that
an IP is a better x-ray detector of a highresolution PIXE spectrometer compared with xray films or position sensitive proportionalcounters. It requires a short measuring time
(1.5 hours) and a small amount of specimen(1.5 x 0.3 mm2); it achieves a high energy
resolution; and a wide energy range is detectable

simultaneously.
References
1) K. Takahashi, J. Miyahara, and Y. Shibahara: J.
Electrochem. Soc., 132, 1492 (1985).
2) H. Kamada, R. Inoue, M. Terasawa, Y. Gohshi, H.
Kamei, and I. Fujii: Anal. Chim. Acta, 46, 107(1969).
3) K. W. Hill, B. L. Doyle, S. M. Shafroth, D. H.
Madison, and R. D. Deslattes: Phys. Rev., A13,
1334 (1976).
4) F. Folkmann: Proc. 6th Intern. Conf. on PIXE,Tokyo Japan. Nucl. Instrum. Methods, B (in press).

-126-

RIKEN Accel. Prog. Rep. 26 (1992)

111-5-13. Total Reflection X-Ray Photoelectron Spectroscopy

J. Kawai, S. Hayakawa, S. Suzuki, Y. Kitajima, * T. Urai, K. Maeda, and Y. Gohshi
Total reflection x-ray photoelectron spectroscopy (TRXPS), which has been proposed bysome of the present authors and coworkers,I) is asurface characterization method. The excitation
x-rays impinge on a specular surface and go
through total reflection. Then the x-rays do not
penetrate deeper than the evanescent length fromthe surface. The incident and reflected x-rays
form a standing wave on the surface. The
intensity of the standing wave is four times asstrong as that of the incident x-ray beam.
Therefore the TRXPS will be a powerful tool forsurface characterization when the next
generation synchrotron radiation source isrealized. 2) Another advantage of the TRXPS isthat the background in the ordinary x-ray
photoelectron spectroscopy (XPS) due to theinelastic scattering of electrons which arephoto ionized below the surface is reduced to lessthan one half when the TRXPS technique is used
as was numerically simulated using opticalconstants for x-rays.I)

MCP

~:'1A

_

"

=

f,. . . . .,AI I " " I'~ I

SamPle

'0
CD
N

<U

...Eo

c

>::
U)
c

CD
C

1

2

3

Fig. 2. Glancing-angle dependence of reflected x-ray
intensity (a), sample current (b), andphotoemission current (c) for 2 keY x-ray beam
impinging on GaAs wafer.

~~counler~.

-

Glancing angle [deg]

Amp.

-

how strong it is, one believes that it has no
physical meaning. However, based on the
traditional manner in which experiments aredone at the RIKEN linear accelerator (RILAC),
where the target (sample) current is always
measured to monitor the ion beam stability as
well as to know the total current of the ion beam,
we have added a circuit to measure the sample
current in the prototype TRXPS spectrometer asshown in Fig. 1.

I

A

...

Fig. 1. Schematic illustration of the experimental setup.

We have designed a prototype TRXPS
spectrometer to check the numerical simulation
results, and measured the photoelectron spectrausing a synchrotron radiation source at the Photon
Factory, KEK, as shown in Fig. 1. The sample was
GaAs single crystal wafer, and the beam size was
5 x 0.2 mm 2 . The x-ray energy was 2 keY
monochromatized by an InSb double crystal
monochromator. We measured the sample current
during the TRXPS measurement excited by thesynchrotron radiation as a function of the glancing
angle of the x-rays to the sample surface.
Usually, when one measures the XPS spectra, one
does not measure the sample current, because it isbelieved to be negligibly small, and, no matter

The sample current had a maximum at thecritical angle of the total reflection as shown in
Fig. 2. This is the first observation of theexistence of the sample current maximum at thecritical angle. The behavior of the photoelectron'current and the sample current was similar eachother. The sample current was of the order of
10-11 -- 10-10 A.
In conclusion, though we have not yet obtained
high resolution TRXPS spectra, it has been foundthat the sample current has a maximum at thecritical angle of total reflection. This effect will
become a useful technique to characterize surfaces(e.g., to determine oxide layer thickness,
adsorbates, and amount of defects on the surface)or to determine the critical angle.
References
1) J. Kawai, M. Takami, M. Fujinami, Y. Hashiguchi, S.
Hayakawa, and Y. Gohshi: Spectrochim. Acta, 478,
983 (1992).
2) Y. Hashiguchi: SPring-B PROJECT, Part II, Scientific
Program, Draft, The JAERI-RIKEN SPring-8 ProjectTea~ p.114 (1992).

* 'Photon Factory, KEK-127-

6. Material Analysis

RIKEN Accel. Prog . Rep. 26 (1992)

111-6-1. Molecular Orbital Calculation of Sulfur K P X-Ray Spectra

J. Kawai, E. Uda, and M. Uda
High resolution Klh,3 (K-M3,2) x-ray fluorescence spectra of the elements of atomic number
between 12 and 17 have complicated line shapes
reflecting the valence electronic structure of thecompound. However the fine structures of the xray spectra are not well understood still now.
Therefore we have tried to reproduce the x-ray
fluorescence spectra quantum chemically using amolecular orbital method. We have chosen sulfur
because it has various oxidation states (theformal oxidation numbers are 6+, 4+,2+,0, and 2-),and also because the sulfur spectra of various
compounds were measured with very highresolution.
We have assumed that the KfJ line shapeequals to the local (sulfur atom site) and partial(3p) electron density of states (005).2,3) The 5 3p
005 was calculated by the net 3p atomic orbital
population in the LCAO approximation using theOV -Xa LCAO-MO method. 4) We havecalculated the Kf31,3 line profiles of various sulfur
compounds: covalent and ionic compounds; solids
and molecules; and compounds of various
oxidation numbers. For infinite size solids orlarge molecules, we have used the molecularcluster approximation.
Figure 1 shows a representative result of thepresent study using C6Hs503Na. Though
C6Hs503Na is an ionic solid, the local structureof it is represented by molecular clusters, 503 2- or
C6HS503-. Therefore we have calculated the xray spectra of both 503 2- (Fig.lb) and C6HS503(Fig.lc). The experimental spectrum of solid
C6Hs503Na by Takahashi et al. l ) is also shownin Fig.la for comparison.

In conclusion, we have calculated the Kf3 x-ray
fluorescence spectra of various sulfur compounds,
and the agreement between theory andexperiment is satisfactory even for small size
clusters for all the sulfur compounds we tried.
X-ray energy / eV
2450

Orbital
53s
53p

02s
02p

2452eV014
82
32462 eV
34
22

32
12

2466 eV025
15602470 eV36092

The experimental spectrum (Fig.la) has four
spectral components (2452, 2462, 2466, and 2470eV), which are well reproduced by thecalculation of 503 2-. However, the larger cluster
calculation yields additional 2458 eV peak(Fig.lc), which is found as a small shoulder in theexperimental spectrum. The molecular orbital
assignment is easier when the cluster has asimpler structure.
The molecular orbital
assignment is shown in Table 1.

2460

2470

2480
1.0_
"0

/.

Q)

.~

n;
E
\0.5

1.0

g
>-

:t::::
(J)

C

:s
Q)

0.0

50.5
~

>-

:;
c.
o
(b)
c. 0.0 ,.........
n;..aiiii......_ _............,.-..........._
~

€

-20

o
o

-10

0

~

x
. . .. , . . - - "10

20

Molecular orbital X a energy / eV'Eo

10 1.0
c.

M

Q)

Z

0.5

(c)
0.0 '--_=---.-I<.J........L......,......L--1...<..---.&L,................-.;::=.==--_ _----I
-30
-20
-1 0
0
10

Molecular orbital X a energy / eV

Table 1. Orbital component of the x-ray peak of 5032(%).

oFig. 1. Sulfur K{3 spectra of 5032-. (a) Observed
spectrum of C6Hs503Na bI- Takahashi et al.1) (b)Calculated spectrum of 503 - cluster. (c) Calculated
spectrum of C6HS503- cluster. Vertical line: 3p
orbital population. Solid liI).e: 5 3p DOS (vertical line
spectra are convoluted by a 1.S-eV -FWHM
Lorentzian function).
References
1) T. Takahashi, W. Qi, M. Enomoto,S. Nojima, J.
Kawai, and Y. Gohshi: Adv. X-ray Chern. Anal. Japan(X-sen Bunseki no Shinpo), 17, 37 (1986).
2) D. 5. Urch: J. Phys. C: Solid St. Phys., 3, 1275 (1970).
3) R. Manne: J. Chern. Phys., 52, 5733 (1970).
4) A. Rosen, D. E. Ellis, H. Adachi, and F. W. Averill: J.
Chern. Plzys., 65, 3629 (1976).

-129-

RIKEN Accel. Prog. Rep. 26 (1992 )

111-6-2. Low-Energy Satellite Structure of Ca-Fe Ka
K. Maeda and J. Kawai

X-ray diagram lines (e.g. Ka and K~) areaccompanied with various types of satellites. In theh~ghly-.sensitive multielement analysis by energydispersIve X-ray spectrometry, satellites emitted frommatrix elements often obstruct the detection of traceel~ment~, even if t~e satellites were very weak compared~Ith therr parent dIagram lines. However, there is little
mformation available as to weak satellites. We report
here the broad satellite structure which was detected on
the low-energy side of the Ka lines of elements ofatomic number Z=20-26. As an excitation source wechose He ions instead of X rays which are generally used
for X-ray chemical analysis. When X rays are used for
excitation, the incident (i.e. primary) X rays are scatteredby the target sample and superimposed on a spectrum of
secondary X-rays emitted from the sample. Ion-induced
X-ray spectra are free from such scattered X rays.
High purity metal sheets of V (>99.99%), Cr(>99.99%), Mn (>99.9%) and Fe (>99.998%), and adisk of CaF2 powders (Merck Spurapur, K<5ppm ,Cd<O.~pp~) were ~sed as target samples. The samples
were IffadIat~d wIth 8 Me V He ions accelerated by
RIL~C. EmItted X rays were analyzed by a Si(Li)semIconductor detector with a resolution of 170 eV at 6
keY. X-ray spectra were measured directly at first using
the arrangement shown in Fig.1a, and after
monoc~om.atizing the X rays using the arrangement asshown m Flg.1b. The latter measurement was carriedout to determine the response function of the Si(Li)detector, which is composed of an escape peak, a lowenergy exponential tail and a low-energy flat continuum.
Slits

II He
II

II

Slits
t»

~

\$\~;,r\$\'"
o~

"

a)

.
1Dc
~

x

'3'

' .

S 1.0 ~
4.5

4.7

escape peakof Mn K~
0.5
"0
Il)

..... 00

o

4.9

,

•

jOA

I
I

I

0.2

I
{)

,".

5.1

I

d
I
I

RAE (or Raman)
type structure

i

I

09
/

1/
00000000000

I

0.0

Cf'

/

o

.!::!
('Q

E

L.

o

Z

0.0"----'-------L--------1J
5.5
4.5
5.0
X-ray energy (keY)
Fig.2. X-ray spectrum in the low-energy region of Ka
obtained from a Mn metal.

A broad satellite structure was clearly observed in
the energy region (around 5 keY) corresponding to K-LL
Auger transitions. A similar structure was found in all
spectra obtained from other samples. From the peakenergies and spectral shapes, the structure may beascribed to the K-LL radiative Auger effect (RAE) typetransition 1) or Ka-L Raman type scattering. 2) The
peak energies and intensities of the structure aresummarized in Table 1. The integrated intensity was
obtained after subtracting the background and the escapepeak of K~, shown in Fig.2, and then correctin a thedetection sensitivity and self-absorption factors. 0
Table 1. Energies and intensities of low energy structure.
Peak energy
Integrated peakElement(keV)
intensity (!Ka, %)
Ca
3.16
0.17
V
4.24
0.20
Cr
4.66
0.12
Mn
5.03
0.08
Fe
5.49
0.07

II He

.5

I~:§
co(/)

ci ~

~"b)

Fig. 1. Sc.hematic drawing of experimental arrangements:a) WIthout a monochromator and b) with amonochromator (Soller slits, an analyzing crystal anda detector were arranged so as to satisfy the Bragg
condition for the Ka line of the target element).
~igure 2 shows the X-ray spectrum in an energy
regIon lower than the Mn Ka. The spectrum was
obtained by subtracting the response function for the
Mn Ka from the directly measured spectrum so that thebackground due to the detector could be removed.

The intensity of the low-energy satellite structure
relative to Ka was determined to be 0.1-0.2 % for
Z=20-26. This implies that the low-energy satellites
are not so weak as to be neglected in analysis of trace
and minor elements. The contribution from thesesatellites should be taken into consideration when thequantitative trace analysis is made by X-ray
spectrometry .
References-130-1) E. Magareter, W. Wegscheider, and K. Muller: X-Ray
Spectrometry, 13, 78 (1984).
2) Y. D. Koo and K. Das. Gupta: Phys. Rev., A42, 5441
(1990).

RIKEN Accel. Prog. Rep. 26 (1992)

111-6-3. Chemical Specification by High Resolution PIXE
T. Isomura, K. Maeda, J. Kawai, M. Takami, and M. Uda
Particle induced X-ray emission (PIXE) spectroscopy has the following three ad vantages
among many X-ray spectroscopies for the purposeof chemical specifica tion:(1) The sensitivity of PIXE is one order ofmagnitude higher than that of X-ray fluorescence
spectrometry .
(~) External beam techniques make it possible toanalyze a sample in atmospheric pressure.
(3) Focused ion beam techniques give informationon the local area of materials.
In particular X-ray emission spectra of valencecore electron transitions, e.g. Kf3 spectra of AI, 5i,
P, 5 and el, reflect the valence electronic
structures. Therefore chemical specification ispossible if the X-ray spectra are measured by ahigh energy resolution crystal spectrometer.
To show the potential of PIXE for chemical
specification, sulfur Kf3 X-ray spectra of 58 and
Mg504 were measured with a Bragg type spectrometer (Fig. 1). The sample was set in air andwas irradiated by a 1 MeV H+ beam produced by
the Tandetron. The beam diameter was 4.5 mm
and the beam current was ca. 100 nA. The spectrometer was positioned at 90° with respect to theincident beam (45° with respect to the sample).
The pressure in the spectrometer chamber was 1
Torr. A 7.5 J.1m thick Kapton film was used as an
X-ray entrance window which separated thevacuum from atmospheric pressure. The emitted
X-rays were collimated by Soller slits (0.17°) andanalyzed by a Ge(1I1) (2d = 6.532 A) flat crystal.

Proportional
CounterProton Beam

The X-rays were detected by a proportionalcounter. The spectrometer was step-scanned at aninterval of a constant Bragg angle and the beam
current was integrated to 10 J.1C for each step. The
dwelling time of one step was shorter than 100
seconds.

K{3

D

Sa

•

MgS04

I

LO

~o
.!:::!

(ij

E

(;

0

zo
2440

2450

2460

2470

X-ray Energy (eV)Fig. 2. Sulfur K{J spectra of S8 and MgS04 . Square dotsshow the raw data and solid lines show the smootheddata.

The measured spectra are shown in Fig. 2. The
data were processed by a smoothing method)
The Kf3' peak, which was characteristic of an 5o bond, was observed at 2450 eV for MgS04. It isalso found that the Kf3 main peak of Mg504 is 1eV higher than that of 58. The oxidation numberof sulfur was determined by these differences inthe spectra. Hurley and White 2) proposed thatthe measurement of only four channels was
required to determine the chemical form of sulfur.
Therefore the oxidation number of sulfur can be
determined by a measurement shorter than 7
minutes (= dwelling time of four channels) if thebeam current is as strong as 100 nA.
In conclusion we have demonstrated that thehigh resolution PIXE distinguishes between sulfur(S°) and sulfate (5042-) in air with a spatial
resolution of -1 mm2.
References
1) A. Proctor and P. M. A. Sherwood: Anal. Chern.,

100mm

52,2315 (1980).

Exit Nozzle

2) R. G. Hurley and E. W. White: Anal. Chern., 46,
2234 (1974).

Fig. 1. Experimental setup for high resolution PIXE.

-131-

RIKEN Accel. Prog. Rep. 26 (1992)

111-6-4. Singularity of Clay Minerals and Iridium Concentration at a
Cretaceous-Tertiary (K-T) Boundary
K. Tazaki, M. Aratani, M. Yanokura,
K. Kaiho, * and S. Noda**
The K - T boundary sediments have relatively
high Ir concentrations suggesting that an asteroid struck the Earth and caused mass extinctions
at the end of the Cretaceous. 1) Spherical clays
heated probably by shock were found in the
Cretaceous-Tertiary (K -T) boundary sedimentsin the eastern district of Hokkaido, northern
Japan. 2) Mineralogical and chemical investigations of the claystone have been carried out by
the use of X -ray powder diffraction, high resolution electron microscope, energy dispersive Xray and heavy ion Rutherford scattering (HIRS
analysis) .
Heavy ion probes of 4°Ar4+ or 4°Ar 6 + (50MeV) ,84Kr 9+ (131.1MeV) and 129Xe 13 + (164. 7Me V) wereused. HIRS analysis of the clay powder « 2,um)
from the K -T boundary layer using 84Kr 9+ (13l.1
MeV) at glancing detector angles of 60 and 30
revealed the existence of Ga, Zr, Mo, In and a0.10

trace of Ir (Fig. 1).
In the sedimentary layers just above and below
the K - T boundary, the content of Ir was under
the detection limit. Sample 520-1 from the K - Tboundary layer indicated the existence of Ir at
glancing detector angles of 40 and 50 (Fig. 2) .
0

0

5

10

84 Kr9+3

EO='31.6MeV

10

81 =30·82=4(j1

10

0

84Kr 9+131.1 MeV
2mA
61 =15·2

10

O~~---r~~~~~L~I~~--~---A.

82 =60·256

Channel Number
-

--

-

Fig. 2 . HIRS energy spectra of the black-grey clay showthat Ir is contained in the sediment (sample 520-1) at i
the K - T boundary.
I

Mineralogical examinations of a continuous
stratigraphic section spanning the K - T boundary 'revealed that the spherical interstratified clays
in the K - T boundary layer are largely
decomposed. The spherical clays showed characteristic stacking disorder of 14 A, 10 A and7 A phases. These results suggest that there
were heating events in the K - T boundary.
Io~~--~----------~~~~~~

512
A
I.
Channel Number171mm 204mm

Fig. 1. HIRS energy spectra of the black-grey clay at
the K - T boundary show that heavy metals arecontained in sample 520-1.

References
1) W. Alvarez, E.G. Kauffman, F. Surlyk, L.W.
Alvarez, F. Asaro and H. V. Michel: Ceol. Soc.
A mer., Special Paper, 190, 423 (1982).
2) K. Kaiho and T. Saito: Proc. Japan Academy, 62,
145 (1986).

• Tohoku Univ.
.. Inst. Ind. Sci. Technol.

-132-

RIKEN Accel. Prog. Rep. 26 (1992)

111-6-5. Structural Water in Volcanic Glass
K . T aza k1· ,T. Tl'ba , * M . Aratarii, and M. Miyachi * *Hydrogen and deuterium distribution in the
volcanic glass from Mt. Daisen in Tottori Prefecture, SW Japan was examined by heavy- ion
Rutherford scattering using the RIKEN heavyion linear accelerater (RILAC) 1).
A 50MeV Ar4+ or Cu 2 + beam of 50nA was used
as incident particles. The beam size was about
1. 5mm X 3mm on a target angled at 45°.
Quantitative energy dispersive X -ray analysisof the glass grains gave 77-78% Si0 2 , 12-13%
A1 2 0 3 , 1.1-l.9% FeO, 1.0- l.3% CaO, 3.3-3.9%
Na 2 0 and 3.0-3 .3% K 2 0 suggesting fresh dacitic
glass. The DT A curve, free from any visible
endo- or exothermic peaks, is indicative ofneither clay minerals nor crystalline materials(Fig .1) .

10

4

4i

c
~
3
s::. 10

H

~

C
~

o

o

10

1

10

10~L-~____~____~~~~~~~__~
00
512
Channel Number

Fig. 2 Energy spectrum of the volcanic glass using ,HIRS showing uniform distribution of structural water.
3
10

o

TG

~

.s

3

- -I

~

0>2

4i

~

OTA
-)

-5

-2

-IS

-3

-15

Channel number

Fig . 3 Energy spectrum of recoiled hydrogen, deuterium and oxygen ions (35 to the incident argon ion
beam) .
0-29

-5L-~--~~·~~-~OO~·~~~~~·~--~_~·~~I=Mf~-~
Temperature (C)Fig . 1 Differential thermal analysis (DTA) and thermogravimetry (TGA) of glass grains.

Heavy- ion Rutherford scattering (HIRS)
depth profiles indicated high contents of H, 0,
Si, Ca and Fe in the volcanic glass (Fig. 2) .
The profile showed no significant difference
between the outside and the inside of the structure. The hemispherical hydrogen slope showedthat hydrogen atoms are distributed uniformly in
the glass with no evidence of surface absorption.
The data indicated that the structural water is in

uniform structural distribution with 0, Si, Ca
and Fe. High resolution HIRS showed not onlyhydrogen but also a deuterium ion spectrum(Fig. 3).
Another volcanic glass of a similar age, collected from Mt . Aira in southern Kyushu, Japan
was also analysed by HIRS for comparison.
Spectra of the Aira glass also showed the presence of structural hydrogen, even though theamount of water was five times less than that in
the volcanic glass from Mt. Daisen.
References
1) M. Aratani: Radioisotopes , 37, 43 (1988).

• N atl. Sci . Museum•• General Education , Kyushu Univ.

-133-

IV. NUCLEAR DATARIKEN Accel. Prog. Rep. 26 (1992)

IV -1. Status Report of the Nuclear Data Group
Y. Tendow, A. Yoshida, Y. Ohkubo, A. Hashizume, and K. Kitao

The Nuclear Data Group has been continuing
the following data activities since previous
years.
(1) Nuclear reaction cross-section data
(EXFOR)
Compilation of nuclear reaction crosssections induced by charged particles into the
EXFOR format has been continued. We havebeen restricted our scope of compilation to the
production cross section for only 20
radioisotopes commonly used in the biomedical
application field; lie, 13N, ISO, 18F, 28Mg, 52Fe,
67Ga, 68Ge, 74As, 77Br, 82Br, 77Kr, 81Rb, 82mRb,
111 In, 123Xe, 127Xe, 123 1, 1241 and 125I.

New measurements for these isotopes rarely
appear in recent references. However, aconsiderable number of old data are still
missing in the EXFOR master file. For thecompleteness of the EXFOR master, we started
to pick up missing works. About 60 papers
have already been found so far.
The
compilation of these data into EXFOR format is
now in progress. There are many useful
medical radioisotopes other than our 20
nuclides. We are considering to expand ourscope of choice to a wider range of isotopes.
A transmission tape R007 containing thecorrected and revised EXFOR files that
previously transmitted by us as a tape R006 has
been sent to the IAEA Nuclear Data Section(NDS) this year.
Cross section data for the production ofradiobromine isotopes especially 75Br weresurveyed extensively. 2) Radiobromine is oneof the useful members of the widely usedradiohalogen isotopes in medical diagnosis andbiochemical studies.
(2) Evaluated nuclear structure data file
(ENSDF)We have been participating in the ENSDF
compilation network coordinated by the
Brookhaven National Nuclear Data Center(NNDC). The evaluation and compilation for

A = 129 mass chain nuclides are in progressand reaching the final stage of completion.
(3) Nuclear structure reference file (NSR)
We are engaged in collection and compilationof secondary references (annual reports,
conference proceedings etc.) published inJapan since previous year into the Nuclear
Structure Reference (NSR) file and sending it
to NNDC. The NSR file is offered for the online retrieval service by NNDC and also
published periodically as the RECENTREFERENCES.
Compilation of the 1990 references has been
completed and sent to the NNDC. Secondary
sources surveyed are following annual reports(in code name in NSR); RIKEN (RI K EN
Accel. Prog. Rep.), JAERI-TLV (JAERI
Tandem, Lin. & V.D.G.), INS (INS Univ.
Tokyo), VITAC (Univ. Tsukuba Tandem
Aeeel. Center), RCNP (Res. Center Nuel.
Phys. Osaka Univ.) and CYRIC (Cyelo.
Radioisot. Center, Tohoku Univ.).
Compilation of the new 1991 references
along with some missing reports of 1988
through 1990 is in progress.
(4) Others
The IAEA Consultants' Meeting on
Technical Aspects of the Co-operation of
Nuclear Reaction Data Centers was held on 1 3 September 1992 at the NDS in Vienna.
Participants from nine data centers in the world
mainly discussed matters of technical aspectsof EXFOR and CINDA as well as NDS'schangeover from the mainframe computer to a
VAX system.
References
1) Y. Tendow, A. Yoshida, Y. Ohkubo, A. Hashizume,
and K. Kitao: RIKEN Aeeel. Prog. Rep., 25, 154(1991).
2) Y. Tendow, A. Hashizume, and K.Kitao: This

-135-

report, p.136.-

RIKEN Accel. Prog . Rep. 26 (1 992)

IV -2. Radiobromine Nuclides and 75Br Production Cross Section
Y. Tendow, A. Rashizume, and K. Kitao
Radioactive halogen isotopes are widely used
for labelling organic compounds of biomedical
use as substitutes for hydrogen atoms. 18F and
123 1 have been commonly used for in vivo
functional imaging in diagnosis and biomedical
studies. Radiobromine is also found to be
useful in the same application. An advantage ofusing radiobromine is in that several isotopes
from 75Br through 82Br are available according
to their physical properties such as half-life or
decay mode. Of all the radiobromines, 77Br has
been most extensively used in a gamma camera
because of its moderate half-life (57 h) and Ee
decay with a very weak positron emission rate
(0.74 %). 1)
76Br (16 h) is also used in the positronemission computed tomography (PECf) but it
has a disadvantage in positron decay properties;
a high positron energy (3.98 MeV) and a low
emission rate (57 %).
82Br is a 13- decay isotope and produced byan (n, y) reaction in low specific activity. It is
not suitable for the in vivo imaging application.
82Br appears as an impurity activity in the natS e(p, xn)15.76.77Br reaction for easy production of
a neutron deficient radiobromine mixture.
75Br would be the most convenient isotope for
PECT having a moderate half-life (1.6 h) and aproper positron energy (1.74 MeV) with a highemission rate (75.5 %). 75Br is produced
through various reactions; 76Se (p, 2n), 76 S e(d, 3n), 76S e eRe, 3np), 75 As eRe, 3n), 75 As(a, 4n) and an indirect reaction nat B r (d,1000 ::::::::::::::::!::::::::::::::::!::::::::::::::::!::::::::::::::::!::::::::::::::::~::::::::::::::::

xn)75Kr - 75Br. 76Br is the main impurity
mixed through these reactions with 1 -- 3 %content typically. The excitation functions forvarious reactions are shown in Fig.l and thecross section data are summarized in Table 1.
Table 1. Cross section data for 75Br production.
Reaction
76Se(p,2n)Energy (MeV)a max (mb)Ref.

16.5 - 34.5
15.8 - 40

520

2)

410

3)

76Se(d,3n)21.8 -44.3

370

2)

76Se(1-Ie,3np)
75As(i-Ie,3n)26.5 - 35>53

4)

15.8 -41.4

203

2)

15.2 - 62.2

352

5)

7sAs(a. 4n)

40.3-71.7

1862)

42.6-106

268

5)

60-80

4

6)

'*Br( d.xn),5Kr_ 7~r

Of all these reactions, 76S e (p, 2n) and 75 As
eRe, 3n) are most suitable for the 75B r
production. To improve the resistivity to thehigh beam current, Cu-Se or Cu-As alloys are
employed as target materials. 75Br is recoveredby the high temperature dry distillation oftargets after the bombardment. The 76Se (p,2n) reaction gives the highest yield and purity.
Disadvantage of this reaction is that an enrichedtarget material has to be employed. The 75 As
eRe, 3n) reaction is also a convenient method.
Advantage is in that natural arsenic can be used,
but the yield is lower than that of 76S e (p, 2n)reaction.

• • • • • • • • • • • • • • • • ~ • • • • • _ • • _ . _ • • • • • {_ • • • • • • • o • • • • • • • ~ ___ • • • o • • • • • • • • • ~ • • • • • • • • • • • • • _ . _ { • • o _ • • • • • • • • • • • •~~~a~~~I:J:!
i • i * i

o ~*

i~

References
1) K. Kitao, A. Hashizume, Y. Tendow, Y. Ohkubo.
and K. Sueki: RIKEN Accel. Prog. Rep., 21. 192~~ l00-~I~"-- - IJ- '---E"~~I------~-- -------'-/b::::::::::::::::t:::::::::::::::t:::::::::::::::t::.::::::::::t:::::::::::::::t:::::::::::::::

lO : : :~: i::I:::::::::::f::: ~ ;[;~ ~1;!n) ,1~--------~--~----~--~--~

10

20

30

40

50

MeV
Fig. 1. Excitation functions for

7S

60

70

Br. (ref.2)- 136 -

(1987).
2) A. M. J. Paans, J. Welleweerd, W. Vaalburg. S. Reiffers,
and M. G. Woldring: In!. J. Appl. Radiat. Isot., 31. 267(1980).
3) Z. Kovacs. G. Blessing, S. M. Qaim, and G. StBcklin:
Int. J. Appl. Radiat.lsot., 36, 635 (1985).
4) He Youfeng, S. M. Qaim. G. SWcklin: Int. J. Appl.
Radiat.lsot., 33, 13 (1982).
5) Z. B. Alfassi. R. Weinreich: Radiochim. Acta. 30, 67(1982).
6) S. M. Qaim, and R. Weinreich: Int. J. Appl. Radiat.
Isot .• 32, 823 (1981).

V. DEVELOPM ENT OF ACCELERATORFACILITIES1. Ion Accelerator Development

RIKEN Accel. Prog . Rep . 26 (1992)

V -1-1. Recent Development of RIKEN 10 GHz Electron Cyclotron
Resonance Ion Source
T. Nakagawa, T.Kageyama, M. Kase, A. Goto, and Y. Yano
In order to increase the beam intensity of highly
charged ions from an electron cyclotron resonance ion
source(ECRIS). it is surely necessary to increase theelectron density of plasma or to prolong the exposure
time of ions in the electron cloud, because only theefficient way to obtain highly charged ions is the
successive ionization. Several methods for increasing
the electron density have been sliccessfully used in manylaboratories 1-3) • One of the methods for increasing theelectron density is to insert electrons into the plasma. In
order to make such a condition, we changed the structmeof the lust stage of .RIKEN 10 GHz ECRIS, which isso-called the plasma cathode method.
Figure 1 shows the schematic drawing of the fIrst
stage for the plasma cathode method. The design andperfonnance before the change of structure of the lIrst
stage is described in Ref.4. The fust stage is isolated
from the second stage electrically. An acceleration plate
which has a central hole is placed in front of the fIrst
stage and connected with the second stage electtically. A
negative bias voltage is supplied between the fust stage
and the acceleration plate to extract electrons from thefust stage to the second stage.

10em
RFl0GH%~

QuanzTube

first, second, and extraction stage are 5-7x 10-6 , 46xI0-7 ,and 6-8xlO- 8 Torrs, respectively. These values
are eight or nine times as low as the values obtained
without using the plasma cathode method. The beam
intensity of Arll+ increases from 30 to 80 e~A, andthat of Kr20+ increases from 0.6 ellA to 8 ellA. It isclear that the beam intensity of the highly charged ionsare remarkably increased by using this method.
l~--------------~----~---

14N

-<

40Ar
84Kr

::1.
~

'-'

~

.t-

~

-==e
~

I-C

=
~

\

~

.11------------...!..-..-------I
5
15

Charge State
Gas Inlet

Fig.2. Beam intensities of nitrogen. neo~ argo~ andkrypton ions as a flmction of charge states. Openand closed circles are the results obtained without
and with using the plasma cathode method.
respectively.

References

Fig. I. Schematic drawing of the first stage of RIIffiN 100HZECRIS for the Plasma cathode method;l)R. Geller: Annul. Rev. Nucl. Part. Sci.• 40. 15(1990) and

Figure 2 shows the beam intensity for highly
charged nitrogen, neon, argon and krypton ions as afunction of the charge stage. The RF powers of the frrst
and second stages are 0 and 800W, respectively. The
extraction voltage is 10 kV. The gas pressures of thereferences therein2)Z. Q. Xic. C. M. Lyneis. R. S.Lum and A. Lundgem:
Rev. Sci. Instrum..62. 775(1991).
3)T. N*agawa. T. Kageyama: Ipn.I. Appl. Phys.• 30.
L1588(1991).
4)K. Hatanaka and H. Nonaka: PxOc. Int. Cont. Physics ofMultiply Charged Ions and Int. workshop of ECR Ion
Source, Grenoble. 1988, I. Phys.,Cl. 821(1989) .

-137-

RIKEN Accel. Prog. Rep. 26 (1992)

V -1-2. RIKEN High Intensity Polarized Ion Source andDeuteron Polarimeters
N.Sakamoto, H.Okamura, H.Sakai, T.Uesaka, T.Kubo, N.lnabe,
K.Ikegami, J.Fujita, M.Kase, A.Goto, YYano, and K.Hatanaka
The assembling of a high-intensity polarized-ion
source (PIS) for the injector AVF cyclotron was fmishedin this May. We are presently trying to upgrade theperfonnance of the PIS.
In July we succeeded in getting a 14MeV polarized
deuteron beam from the cyclotron for the frrst time. The
typical intensity obtained at the exit of PIS was 20J.lA;
the polarizations of the extracted beam were as shown in
Table 1.

12C(d,p)13 C (g.s.) reaction at 14MeV. For this purpose
we have measured the complete set of the analyzing
powers ( ~ , Ayy , Azz and Axz) of this reaction at
the Kyushu University tandem accelerator laboratory(Fig. 1).

Table 1. The polarizations obtainedpolarization modes
pure vector

up

down
pure spin states m=+ 1
m= 0
m=-l

Pz
0.40
0.42
0.46
- 0.07- 0.44I7z-

0.38- 0.36
0.28

The PIS still has drawbacks mainly in two places: thefIrst one is concerned with the dissociator. The "white
stuff' comes from the inner wall surface of adissociation Pyrex tube which is sputtered by rfdischarge plasma and builds up in the cold nozzle(35K)
for cooling the atomic beam. Another is concerned withthe beam extraction system of the ECR ionizer. It has
not yet been well optimized and therefore theextraction effIciency is very low. We are modifying theextraction electrodes to achieve higher efficiency.
The PIS can provide all modes of polarizations of pure
vector, pure tensor and pure spin states by thecom binations of two strong and two weak field rf
transitions. The spin direction can be controlled byusing a Wien filter which is installed at the exit of the
PIS. Two different polarimeter systems monitor thevector and tensor polarizations( Pz and PZl ) and theirpolarization axis of the accelerated deuteron beam. Oneof them is placed between the AVF and Ring cyclotrons.
The polarimetry will be made by utilizing the-1.0-1.0 .........................................................................
75 100 125 160
26 60 75 100 125 150
J..,U...J..I

25

50

SCATTERING ANGLE [lab ]Fig. 1. Analyzing powers of 12c(d,p)13C [Ed=14MeV]

Another polarimeter for a 270MeV deuteron beam isinstalled on the beam transport line of the Ring
cyclotron. In this November we, for the first time,
accelerated a polarized deuteron beam up to 270MeV by
the Ring cyclotron. We measured the vector and tensor
analyzing powers (Ay and Ayy) of the H(d,d)H reaction
at the scattering chamber ASCHRA. These data will be
used as fundamental data of the polarimetry. Detailed
analysis is now in progress.
Since the complete sets of analyzing powers(Ay,Ayy,Axx and Axz) are needed to detennine thepolarization axis of a deuteron beam, an experiment tomeasure Axx and Axz of the H(d,d)H reaction at
270MeV is scheduled for the next February.

- 138-

RIKEN Accel. Prog. Rep. 26 (1992)

V -1-3. Development of the LNA Laser for Polarized 3He Ion Source of
the Injector A VF Cyclotron (III)A. Minoh, K. Ogiwara, and T. Fujisawa
It was shown by Leduc et all) that the laser
frequency has to be tuned on one of thehyperfine components of the 3He 2S-->2P
transition to make the nuclear polarization of
3He by the optical pumping. In our previous
experiment, the O.lmm air gap etalon reduced
the spectral width of the LN A laser from
3000Hz to 300Hz and it was believed that
another etalon must be set in the cavity to
reduce the width to the Doppler width of the
20Hz(in 2S-->2P transition of 3He).2) Thus
the free spectral range( FSR ) of the second
etalon should be more than 300Hz. We
estimate the spacing of the etalon is 2--3mm
because the second etalon must tune the laser
frequency on one hyperfine level in the widthof 300Hz.
We made experimentally sure the cavity
parameters by using the LN A laser of theInstitute for Molecular Science, because theoutput power of our Ar+ laser exciting the
LNA laser is too weak to insert two etalons in
the cavity.
Optogalvanic effect induced by the laser
beam was observed to study the tuning on thehyperfine transition. 3) The optogalvanic cell
was of 15mm inner diameter and 25cm long.

The cell was filled with O.4Torr 3He gas andthe DC discharge current was lOmA.
The output power of the LNA laser was
15mW. A part of the laser beam was split by anon-coated glass plate, and was introduced into
the optogalvanic cell.
The LNA laser frequency was scanned from9228.59cm- 1 to 9230.28cm- 1 by the 2mm air
gap etalon controlled by ,a piezo-electrictransduc,er. The optogalvanic signals
corresponding to the all hyperfine components
of 2S-->2P transition were observed. The
observed intensity of the optogalvanic signal
was as strong as 60m V p-p and a saturation dip
was observed at the center of the Doppler
broaden line. We plan to use this saturation dip
to lock the laser frequency on hyperfine level
during the long time optical pumping.
The threshold pumping power of the Ar+
laser was l.3W for the LNA laser inserted two
etalons. The maximum power of our Ar+ laseris 1.6W. Then the output power of our LNA
laser will be too weak to obtain the sufficient
nuclear polarization.
We plan to measure the polarization of the
3He nucleus by measuring the circular
Rotating

fijPomri~:om~~Br

1J4Plale1083rvn~~~~,-e___~llm.rt~~~ ~3 He Discharge

Tube

-C\

Photo
Diode

~

Ught

SOUrs8

Rotating Angle

12 bit A-D
Convertor

Reference

PC-9801
ComputerFig. 1. Detection system of the nuclear polarization of 3 He .

-139-

polarization of the 667.8nm light of the 30->2P transition. 2) The detection system isshown in Fig.l. The l083nm light from thelaser is circularly polarized by a 1J4 plate andfed into a 3He discharge tube. An interference
filter cuts off all the light except the 667.8nm
light. The 667.8nm light is focused by a lens,passes through a 'A/4 plate rotating constantly
and a linear polarizer, and measured by aphotomultiplier. The output signals from thephotomultiplier are sampled at each rotation
angle of 9oo of the 'A/4 plate and stored in a
PC-9801 personal computer through a 12 bit AD convener. After several tenth rotation of the
1J4 plate, the polarization of the 667.8nm lightis calculated by comparing the difference
between the data of the two groups

corresponding the diagonal angle of the rotating
1J4 plate. This system detects one percent of
the circular polarization of the light. This
analyzing power corresponds to a few percent
nuclear polarization.
We thank Dr. Morita and Dr. Kumakura forproviding us an opponunity to use the LN A
laser system of the Institute for Molecular
Science.
References
1) M. Leduc. S.B. Crampton. P. I. Nacher. and F. Laloe:
Nuclear Science Application. 1. 1 (1983).
2) A. Minoh. and T. Fujisawa: RIKEN Aceel. Prog. Rep .•25, 103 (1991).
3) L. D. Shearer. and Pedetha Tin : I. Opt. Soc. Am. B. 6.
1771 (1989).

-140-

RIKEN Accel. Prog. Rep. 26 (1992)

V -1-4. A Beam Chopper for RILAC Using High Speed

MOS-FET Modules
M.Hemmi, H.Kumagai, and Y.Miyazawa
In order to get a short beam pulse
from RILAC, a new beam chopper was
installed in the beam injection line. The
chopper was composed of a deflector anda simple pulser, as shown in Fig.l.
The deflector has two parallel plateelectrodes (8 cm in length along the beamline and 8 cm wide) with a gap of 2.6 cm.
When a pulsed high voltage (3kV) is applied
to the deflector, the beam from a 500 kV
inj ector is deflected and stopped by a beam
slit located just in front of the RILAC firstcavity.

'ffr.8 17

PPAC
Ar

Vln/:333kV

IO!

+3kV DCCHANNELi -- -- -- --I
I
I~H..!'!.-!1~ _ _ _ _200n51111 .11 ,.,111 ~ III

av

LOGIC

51.37M.V

Rf:35MHz

ill

II

I

I

~UM8ER~ TimeFig. 2. A time spectrum of 51.37 MeV argon
beam on the 35 MHz rf phase . It was
detected by a Parallel Plate Avalanche
counter .1) The time resolution of thecounter is 0.67 ns.

:
I

J

MOS-FET Module ~~:::::r..;:.O:..::UT~PU~T
DEFLECTO~

z:::::.;ii'

Fig. 1. Conceptional diagram of the beam
chopper.
The pulser for the beam chopper is madeby using a commercially available MOSFET module,· This module is capable ofswitching 8kV, 30A with a turn-on rise timeof 5 ns and conveniently providing 10 kV
isolation between the power output and the
TTL input port. To reduce the rise andfall time of the pulse two of the modules
were connected in series and operated in
the push - pull mode. The input signal isisolated with a high speed photo - coupler
to eliminate common noise.

The pulser can drive the deflector
electrodes having a capacitance of 16 pF
at 3 kV with rise and fall times of about
20 ns. The pulse width of chopper can bechanged from 200 ns to DC operation.
Maximum repetition rate is 40000 pps.
Figure 2 shows a time spectrum of apulsed beam accelerated by RILAC witha phase modulation of 200 ns which wassynchronized to the master oscillator of
RILAC. Six beam pulses in a single bunch
were observed on the chopper modulation
pulse.
References
1) H. Kumagai et a1.: RIKEN Accel. Prog. Rep.,
19, 148 (1985).

• BEHLKE HTS - 81
-141-

RIKEN Accel. Prog. Rep. 26 (1992)

V -1-5. Construction of the Second-Harmonic Buncher for RILAC
S. Kohara, M. Kase, Y. Miyazawa, M. Hemmi,
T. Chiba, Y.Chiba, and A. Goto
The design of a second-harmonic buncher
reported previously!) was modified by taking
into account the following problems:
1) Moderating an increase of rf loss in the low
frequency region.
2) Keeping agood impedance matching to thepower feed line (50 ohm) without making
any adjustment of elements and any external
compensation through the frequency range(34-90 MHz).
3) Reducing as much as possible the parts
placed in vacuum for easy fabrication.
A cross sectional view of the new buncher isshown in Fig. 1. The resonator of the buncher
is of a coaxial quater-wave-length type, which
has two open ends oscillating in phase and at
nearly equal voltage; one end consists of a drift
tube and the other a capacitive voltage divider,through which rf power is fed. The ratio of thedrift tube voltage to the feed terminal voltage is
kept nearly constant, 30, in the frequency
range. The resonant frequency is varied byusing both a movable short and a variablecapacitor instead of using the latter only in theprevious design; this alteration moderates thefrequency dependence of rf loss. Thus low
voltage standing wave ratios (VSWR) on the
power feed line is obtained through thefrequency range. Driving range of the movable
short is 63 cm. Capacitance range of thevariable vacuum capacitor is from 12 to 60 pF.
The drift tube and its opposite electrodes, only
components in vacuum, are sealed off with avacuum feed-through of ceramics insulator.
40

100
90
80

"N

~

Frequency•

Power loss

30

::c

6>.

70

E
CIl
CIl

.sa

u

5

g. 60

~

u..

~
~

20 6:

50
40
30

o

10

20

30

40

50

60

10

Position of the movable shorting plate L (cm)Fig. 2. Positions L of the movable shorting plate (seeFig. 1), power losses, and capacitances of thevariable capacitor calculated as a function of thefrequency. Power losses are calculated for the peakgap voltage of 1.5 kV.

Movable shortingplate

3~-------------------------

Ceramics insulator.!2

Variable vacuwn
capacitor

~
M

Q)

~

2

~

1)1)

.5

Open-end terminal

o 5

"0

E
CIl

10 (cm)Q)

5

Teflon insulator'0:>
Coupling circuit

OL..----IL..----I'-----'----'---'---I.---'
30

40

50

60

70

80

90

100

Frequency (MHz)Fig. 1. Cross sectional view of the second-harmonicbuncher.

Fig.3. Voltage standing wave ratio at the feed terminal
calculated as a function of frequency.

-142-

Resonant frequencies and power losses
calculated with the transmission-line
approximation are shown in Fig. 2. The
resonant frequencies calculated are varied from
39 MHz at 55 cm of position of the movable
short to 90 MHz at 4.45 cm when the variablecapacitor is set at 15 pF. The resonant
frequency of 34 MHz is obtained when thecapacitance is 50 pF and at the position 55 cm.
The maximum power loss is 37 W to get thepeak gap voltage of 1.5 kV. The maximum

current of the variable capacitor is reduced to 20
A from previous 120 A, so that a small size
capacitor is enough for the purpose. VSWR
calculated at the feed terminal is shown in Fig.
3. It is less than 1.55.
The buncher will be completed at the end of .
next March.
References
1) S. Kohara, M. Kase, and A. Goto : RIKEN Accel.
Progr. Rep., 25, 167 (1991).

-143-

RIKEN Accel. Prog. Rep. 26 (1992)

V -1-6. Profile Monitor for Light-Ion Beams with High Energy
M. Kase, T. Kawama,· and I. Yokoyama

A three-wire type beam scanner has been used
for the beam profile measurement at every beamline in the RIKEN Ring Cyclotron.
As its sensor material, a gold-plated tungsten
wire with a diameter of 100 J.1l1l has been used. It
has enough sensitivities for a beam of ionsheavier than carbon with any energy available
here (0.001 - 135 MeV/nucleon). On the other
hand, for light ions, such as proton and deuteronwith energies greater than 100 MeV /nucleon, thesensitivity is very low and sometimes one cannot
measure a beam profile of their low-intensity
beams. It is troublesome especially in case of beamtuning, when a beam intensity must be low enoughto lighten useless radioactivation on chamber
walls and so on.
To solve this problem, a new type of sensor
material was introduced, namely a copper platewith a thickness of 300 J..l.m and a width of 3 nun.
The plate had been made by the chemical etching
to eliminate any mechanical distortion. Three
plates are held on the probe head with a Macor
insulator in stead of three wires in the old typeprobe. 1) Figure 1 shows a view of probe head of
the new profile monitor.

Figure 2 shows the comparison of the beamprofile data obtained with the old and newmonitors under the same .conditions. The newprobe has much higher sensitivity than the oldone, although the two give almost the sameprofile shapes. The enhancement of sensitivity
amounts to be a factor of 100, which corresponds to.the ratio of intersection volumes for the two
sensor materials.
Similar data were obtained
for a 135MeV proton beam.
The new monitor cannot stand for a heatdamage by a 135 MeV/nucleon heavy-ion beamwith an intensity over 100 pnA. Therefore the two
types of probes must be installed together in one
beam diagnostic station of beam lines from the
RIKEN Ring Cyclotron in order to cover the all
variation of beams available here.
Peak c:urrent(35 nANew type

-30

-20

-10

0

10

20

30

Horizontal position (mm)Old type-30-20

Peak c:urrent
3.1 nA

-10

0

10

20

30

Horizontal position (mm)Insulator

BEAM
Fig. 1. A view of new type of profile monitor. A is thesensor plate for a horizontal measurement, B for a
vertical one and C for a 45 deg. line one.

Fig.2. The horizontal beam profile data obtained by two
types of probes for 270 Me V deuteron beam with anintensity of 60 nA. Vertical axes show electric currents
from the sensor irradiated by the beam. The both data arenormalized to their respective peak currents.

Refereoces
1) M. Kase, I. Yokoyama, I. Takeshita, Y. Oikawa, M.
Saito, and Y. Yano: Proc. 11th Int. Conf. on Cyclotrons
and Their Applications, Tokyo, p.443 (1987).

• Swnijyu Accelerator Service. Ltd.

-144-

"-

2. Synchrotron Radiation Sou rce Development

RIKEN Accel. Prog. Rep. 26 (1992)

V -2-1_ Study on the Low a Operation of SPring-8
Storage Ring
H. Tanaka and N. Kumagai
On the normal operation of the storage ring ofSPring-8, the bunch length is expected to be a few
tens psec. Although this value is quite small
compared with the 2nd genera tion light sources
based on the FOOO lattice, it is required by somespecial users to make the bunch length as short as
possible. We study the possibility of theoperation for an extremely short bunch in thispaper.
The bunch length in the light source isdetermined by the balance between radiation
excitation and damping. It is expressed as follows
without the current-dependent turbulence.

shorten the bunch length by reducing (X as apreliminary study. This idea was first proposedby D. A. G. Deacon!) and confirmed by theexperimental study in UVSOR.2) Momentum
compaction factor, (x, is written as the following
form,

(2)

where, E, T, V', a, and crE are beam energy,
revolution time, slope of a RF field, a momentum
compaction factor, and energy spread of
circulating beams, respectively. In theseparameters, T and E are not free and cr E isdetermined by E and geometrical factors. And also
V' cannot be easily increased because it is limitedby the RF power supply. We therefore try towhere C, 11, and p denote the circumference of aring, a horizontal dispersion function, and aradius of curvature, respectively. Theoretically,a can be reduced by vanishing the loop integral
until the second order term of 11 is not negligible.
Since 11 is positive along the ring, negative Tl isintroduced to reduce the integral value at thestraight sections for insertion devices.
We perform the parameter search under thefollowing constrain3 ); the strength of quadrupoles
and sextupoles is less than 0.675 m-2 and 15.75 m-2, respectively.
Table 1 shows the results obtained for the casethat the operation point is fixed at Vx =51.22

Table 1. Lattice data for the case that the operation
point is fixed.

Table 2. Lattice data for the case that the operation
point is not fixed.

crL=

VeV' . ~E
aTE

,

HLC2B

Emittance (nm-rad)

6.96

(1)

LALFA-Bl LALFA-B2 LALFA-B3 LALFA-84
30.6
34.9
31.4
28.3

51.22
16.16
-119.21-40.765

45.38816-32.3-41.1144.49816.332-31.813.,'39.603

44.22
17.16
-83.4
-38.1

44.22
11.16
-81.174-38.24:;~;%t~;:;~t~~~~~:~t~~tt;~~~:~t~

1.46E-04

7.96E..()5

4.64E..()S

4.41E-OS

1.02E..()SUiSp-X at H~T (UI)
Dilp-X at tsr (m)Max BX(m)MaxBY(m)Max Dilp-X (m)Quad.(I/m2)
Ql (0.35m)
Q2 (0.97m)
Q3 (0.51m)
Q4 (0.41m)
QS (0.51m)
Q6 (0.51m)
Q7 (0.41m)
Q8 (0.51m)
Q9 (0.97U1)
Q10(0.35m)
1/2"5ext. (l/m2)
SI (o.h)52 (o.h)53 (o.h)54 (0.5m)
55 (o.h)56 (o.h)57 (o.h)

C
0
30.4
26.8
0.4

-0.2.:
-0.05
39.4
33
0.54

-0.25
-0.05
39.6
32
0.52

-0.26
-0.0
44.66
28.56
0.51

-0.2
-0.05
43.7
38
0.51

-0.2804218 -0.31477036 -0.32143032 -0.3336449
0.3751093
0.3715247
0.3674327
0.3982004-0,4040175-0.3856111 -0.3866937-0.4384298-0.6005168 -0.59130037 -0.58711399 -0.57624131
0.6588736
0.674034
0.6540738
0.6349426
0.6137483
0.633524
0.6349426
0.6295413-0.557599-0.6005168 -0.57310385 -0.5677595-0.610212-0.5639839 -0.58376106 -0.59185676
0.5914277
0.5883734
0.5916253
0.6131862-0.4772537 -0.55852177 -0.564 83411 -0.5470004-0.437183
0.4025077-0.4054399-0.4720318
0.6599572
0.5969747-0.5013098-0.5391905
0.5626772-0.4760235

Tune-X
Tune-Y
Chrom-X
Chrom-Y

3.90425-4.3-3.95936
7.12567-3.95936-2.38462
4.28489-3.2459
6.1845-3.2459-4.0385
7.96025-4.0385-4.0297.8091-4.029-4.45518.79915-4.4551

HLC2B

Emittance (nUl-rad)Tune-X
Tune-Y
Chrom-X
Chrom-Y~}~~ffft~~ftftf~~tDisp-X at HSf (m)Disp-X at tsr (m)Max BX(iii)
Max BY(m)Max Disp-XlD\f
Quad.07m2Y
Ql (0.35m)
Q210.97uiJ
Q3 (0.51m)
Q4 (0.41m)
Q5 (0.51m)
Q6 (0.51m)
Q7 (OAlm)
Q8 Tosfm}
Q9 (0.97m)
QI0(0.35m)
1/2-Sext. (1/m2)
51 (o.h)52 (o.h)53 (o.h)54 -(0.5m)

55
56

57

-145-

(o.h)
(o.h)
(o.h)

6.96

LALFA-Al LALFA-A2 LALFA-A3 LALFA-A4
28.7
40.5
19.3
12.1

51.22
16.16
-119.21-40.769

51.22
16.16
-114.97-41.224

51.22
16.16
-115.25-40.441

51.22
16.16
-115.98-40.80~

51.22
16.16
-117.12-40.91

1.46E-04

1.98E..()4

2.47E..()4

3.07E-04

3.82E..()4

u

-0.1
-0.03
3Q.3

-0.2
-0.06
3Q.4

28.3
0.5

27.5
0.6

-0.3
-0.09
30.5
28.4
0.72

-0.4
-0.13
30.7
29.8
0.84

0
30.4
26.8
0.4
-0.2804218
0.3982004-0.4384298-0.6005168
0.6349426
0.6349426-0.6005168-0.5639839
0.6131862-0.4772537
3.90425-4.3-3.95936
7.12567-3.95936-2.38462
4.28489-0.2819887 -0.2849845
0.4041829
0.3991698-0.4270565 -0.43584623-0.6069119 -0.59887883
0.6305796
0.6231438
0.1082802
0.3525007-0.5395966 -0.17169347-0.5609783 -0.5613091.5
0.6185984
0.6145512-0.4730372 -0.484 95141-2.7372
4,879489-2.737-2.2091
3.89505-2.2091-0.28992387 -0.26994134
0.4072485
0.4044493-0.4302093 -0.4300917"-0.60283015 -0.6082354 90.6163892
0.6193608
0.1718881
0.0054031-0.66188263 -0.0845667-0.5554901 -0.5383457"
0.6250086
0.6211569-0.49278872 -0.5258064-1.77123.0964-1.7712-1.4491
2.5173-1.4491

and v y =16.16. In the tables, HLC2B represents theparameters of the typical operation mode and thevalues for the sextupoles represent one half of the
sextupole strength. We cannot find the proper
operation mode with smaller (l than the typical
one in this condition. This may be because thelattice with dispersion free straight sections is
optimized at this operation point. It is difficult
to completely delete the dependence of fitting
results on the initial condition, even with a goodfi tting routine.

Table 2 shows the results obtained for the casethat the operation point is not fixed. The
momentum compaction factor (l can be reduced
from one half to one fifth of the typical value.
According to Eq. 0), the bunch length can be
reduced down to one fourth of the typical value,
several psec. On the other hand, the naturalemittance becomes 4-5 times larger than the
typical one and the strength of sextupole magnets
becomes strong. Especially in LALFA-B4, thestrength is much beyond the constrain. Although

60 , - - - - - - - - . - - - - . , - - - - y - - - - - , - - - - , - - - - - - , 2.0

50

1.6

8ETAX

~
Z

40

0

1.2 ~

5

UJ

<

~

w

CD

a..

if)

30

a
0.8

:20

0.4

10

o0

<40

0.0

PATH LENGTH [M]Fig. 1. Lattice functions of one normal cell for LALFA-B4.

there is a possibility to reduce the strength of the
sextupoles by the sophistica ted optimization
with the other sextupoles for the harmoniccorrection, it seems not to be easy to obtain a large
dynamic aperture. We show the lattice functions
for the operation mode, LALFA-B4 listed in thetable, in Fig. 1.

References
1)

2)

3)

-146-

D. A. G. Deacon: Phys. Rep. 76, 349 (1981).
H. Hama, S. Takano, and G. Isoyama: Proc.
Workshop on 4th Generation Light Sources,
Stanford, USA, Feb. 24-27, 208(1992).
H. Tanaka and N. Kumagai: RIKEN Accel. Prog.
Rep. 25, 175(1991).

RIKEN Accel. Prog. Rep. 26 (1992)

V -2-2. Estimation of Increase in Vertical Emittance Due tothe Vertical Dispersion Induced by Magnetic Errors
H. Tanaka and A. AndoIn an X-ray region, brilliance of synchrotron
radiations is not limited by their diffraction but
limited by the emittance of an electron beam.
Especially, it is important to the keep verticalemittance small for achieving high brilliance.
The vertical emittance is exci ted by two
mechanisms; the radiation-excitation and thecoupling between horizontal and vertical betatronoscillations. Since the scheme for its reduction
depends on its excitation-mechanism, thecontributions on the vertical emittance from theboth should be estimated to design the reduction
scheme. We have already investigated the effectof coupling between the transverse betatronoscillations on the vertical emittancel) and here
investigate how much the vertical emittance is
excited by the radiation-excitation underpractical magnetic errors in the storage ring ofSPring-8.
The vertical emittance, E y, due to theradiation-excitation is represented as follows,2)
assuming that the partition number of a vertical
damping rate is equal to unity and neglecting theangular divergence of photons emitted by anelectron.

distortion (COD) as a parameter. The caiculationis performed by the simulation code, which ismade of a linear calculation part of
RACETRACK3) and original calculation routines
for statistics and correction. MagnetiC errors
included here are listed in Table 1.
Table 1. Random magnetic errors used in thesimulation.

Dipole Magnet
Tilt Error
Field Error
Quadrupole Magnet

lxl0-4 [rad]5x10-4

Tilt Error
Field Error
Misalignment
Sextupole

2xlO- 4 [rad]5x10- 4[mm]
0.2

Tilt Error
Field Error
Misalignment

2x10- 4 [rad]lxlO- 3[mm]
0.2

Calculation results for three different sets ofrandom magnetic errors, are shown in Fig. 1. The
vertical emittance decreases as the r.m.S. of

10- 4 I!!"---~----:---~---=------.

0)··············t················1················t·············..·%···6·········
1~~ 0 ~ •··············1'················1'···············1······..········f···················.. ·········r················I················1······..........J................

H y = YyT\y2 + 2 CXyT\yT\y ' R+ pT\y ,2··············[················1'···············1······..........[................

Cq=~._h_=3.84XI0-13 ,32V3 21tmc··············r················r···············1·······..·······r······..····..··

where, E, h, ~y, cxy, Yy, p, T\y, and T\y' are the beamenergy, the Planck constant, a betatron, an alfa,
and a gamma functions, a radius of curvature, adispersion function and its derivative,
respectively. The subscript y denotes a verticalaxis. For an ideal ring without magnetic errors,
the vertical emittance defined by Eq. (1) iscompletely equal to zero, because T\y and T\y'vanish along the ring. We calculate the verticalemittance using the residual closed orbit-147-.............. ~ ................i................~ ..~ ........................

iq,ol.~.-1.............. :, ................:.....l!i....... .., ................ ................

4AA

~

1
1
10-12 L....I..............................",..~.............~IoIoIoIIoIllo-...............
10
100
1
0.1
0.001 0.01

l.m.s. Vertical COD [mm]Fig. 1. Vertical emittance versus r.m.s. vertical COD.

vertical COD decreases. It reaches a few tens
pmerad when the COD is corrected below 0.2 mmby the present COD correction system.4 ,5) These

:;
~

• 10-

e

6

-...

w>'
~

~~ 10-8-eo polresults show that the correction of verticaldispersion is not necessary for achieving 1 % ofemittance-coupling defined as the ratio ofvertical emittance to horizontal one. The
horizontal emittance in the storage ring is
expected to be several nm-rad.
In Fig. 2, the vertical emittance is shown
against the maximum vertical dispersion inducedby the random errors. This value can be also
adjusted by using the COD con-ection system. A
good positive correlation between the twoparameters is obtained. To keep the verticalemittance less than 10 pmerad, the maximum
vertical dispersion in the ring should be
suppressed below 1 em.

r.LI"; 10-10

References

"-e

1)

u

>

H. Tanaka and M. Hara: RIKEN Accel. Prog. Rep.,
24, 143 (1990).

~

10-12

0.001
Maximum Vertical Dispersion 11y_m [m]Fig. 2. Vertical emittance versus maximum verticaldispersion.

2)
3)
4)

5)

-148-

M. Sands: SLAC-121 (1979).
A. Wrulich: DESY Rep., 84-026 (1984).
H. Tanaka, R. Nagaoka, K. Tsumaki, K. Yoshida,
and M. Hara: RIKEN Accel. Prog. Rep., 22,
231 (1988).
H. Tanaka, R. Nagaoka, K. Tsumaki, K. Yoshida,
and M. Hara: ibid., p.235.

RIKEN Accel. Prog. Rep. 26 (1992)

V -2-3. Effects of Muitipoie Errors on the Dynamic Apertureof SPring-8 Storage Ring (III)H. Tanaka, Y. Ishii,* and N. Kumagai
At the initial phase of commissioning, beams
are injected into a storage ring with all sextupole
magnets turned off to obtain the beam stability ina short period. In this case, we should avoid thesituation that multipole errors limit the beamstability within a vacuum chamber. From thispoint of view, the previous works 1 ,2) were
performed. On the other hand, sextupole magnets
are turned on at the steady operation to increase
the beam current by suppression of the head-tailinstability. Multipole errors also should notseriously affect the dynamic aperture determinedby the nonlinearity of sextupole magnets in thisoperation phase. We here investigate the effects
of multipole errors on the dynamic aperture with
sextupole magnets turned on.
Figure 1 shows the dynamic aperture using thestrength of octapoles and decapoles as aparameter. The multipole errors used in thiscalculation are listed in Table 1. Under thecondition represented by the empty circles, thedynamic aperture was larger than the chamber
aperture with the sextupole magnets turned off,2)
but it becomes about 25 % smaller than thechamber's with the sextupole magnets turned on.
We see in the figure that the empty symbols

Table 1. Multipole errors used for the calculation of
dynamic aperture. The values for each multi polecomponent in the table represent the ratios to themeasured data 3 ) corresponding to the same
component. The symbols 'R' and'S' denote
the random and the systematic errors, respectively.

6 poleSymbol R

00.•

8 pole10 pole12 pole

S

R

S

R

S

R

S

0.5 5
0.5 5
0.5 5
0.5 5

5
5
1
1

50
50
10
10

0.5
0.1
0.5
0.1

5
1
5
1

0.1
0.1
0.1
0.1

1
1
1
1

represent smaller dynamiC aperture than thefilled ones and tha t there is not a marked
difference between the empty circles and squares.
This means that the reduction of the · dynamic
aperture is due to the octapole components under
the calculation condition. By one fifth reductionof the strength of the octapole components, thehorizontal dynamic aperture recovers from 28 mm
up to 31 mm in the low coupling.
Figure 2 shows the effect of end-shims on the·enlargement of the dynamic aperture. The

25.0

20.0

i

15.0

~

10.0

......;. ......

20

!
5.0

················t·····_· ·······i--····· ·········t······

s: 15

!

..........-.-.t.............·····~·········· ·········~ ................

~
0.0

L-,,---..L-,,---..L-..r.....-...L-..r.....-..L-,,---.L.-.l......-.l..--.l......-.l..--.I-....J.40.0 ·35.0 ·30.0 ·25.0 ·20.0 ·15.0 ·10.0

·5.0

0.0

5

x [mm]
Fig. 1. Reduction of the dynamic aperture du to
the multipole errors with the sextupole
magnets turned on. The solid line represents thevacuum chamber aperture. In this calculation,
the multipole errors listed in Table 1 were used.

It

10

Takasaki Rad. Chern. Establish., Japan Atomic
Energy Res. Inst.

o~~~~~~~~~~~~~~~

-40

-35

-30

-25

-20

-15

-10

-5

0

X [mmlFig. 2. Enlargement of the dynamic aperture due to theend-shims with sextupole magnets turned on. In thiscalculation, the multipole errors listed in Table 2
were used.

-149-

Table 2. Condition of the multi pole errors used in Fig. 2.
The symbols 'R', 5', and each value in the table
denote the same as in Table 1.

6 poleSymbol R S

8 pole10 pole12 pole

R

S

R

S

R

10
1

0.5

5

0.5
0.5

5
0.5

0.1
1
0.1 0.1
0.1 0.1

x

0.5 5

1

~

0.5 5
0.5 0.5

1
1

o

1

S

multi pole errors used in this calculation are listed
in Table 2. The crosses represent the case without
end-shims. The empty triangles and squares
represent the cases with end-shims to correct themulti pole errors of the quadrupole magnets and tocorrect those of the both quadrupole and sextupole
magnets, respectively. In this calculation, it isassumed that only systematic multipole errors are
reduced to one tenth by using the end-shimcorrection. We see in Fig. 2 that; (1) the
enlargement of ,..,10 % is obtained by the end-shimcorrection in the low coupling ratio, (2) the endshim correction is not effective for theenlargement in the high coupling ratio, and (3)there is not a marked difference between the cases
where the end-shim correction is applied to thequadrupole magnets only and to both of thequadrupole and bending magnets.
Figure 3 shows the comparison between the
dynamic apertures with and without themultipole errors. As the multipole errors, those
represented by the empty triangle in Table 2 areused. The multi pole errors do not much reduce thedynamic aperture in this condition.
Figure 4 shows the comparison between the
dynamic apertures with the sextupole magnets
turned on and off. The same multi pole errors as inFig. 3 are used. In this multipole error condition,
the dynamic aperture is about twice larger thanthe chamber's with the sextupole magnets turned
off.

,
• ,

70
60

\

50

....' .

i' 40
.§
)04

30
20

20

i' 15

!
)04

-70

10

-50

-40

-30

-20

-10

0

X [mm]

Fig. 4. Comparison between the dynamic apertureswith the sextupole magnets turned off and on in thepresence of the multipole errors. The filled circles
and the empty squares denote the dynamic
aperture with sextupolc magnets turned off and on,
respectively.

5

o

-60

~~~~~~~~~~~~~~~

-40

-35

-30

-25 -20 -15
X [mm]-10-50References

Fig. 3. Comparison between the dynamic apertureswith and without the multi pole errors under thecondition that the sextupole magnets are turned on.
The empty squares and the filled circles denote thedynamic aperture with and without the multi poleerrors, respectively.

1)

2)
3)

-150-

Y. Ishii, H. Tanaka, and N. Kumagai: RIKEN Accel.
Prog. Rep., 25, 180(1991).
Y. Ishii, H. Tanaka, and N. Kumagai: ibid, 25,
182(1991).
J. Ohnishi, H. Takebe, K. Kumagai, and S.
Motonaga: IEEE Trans. Mag., 28, No.1, 546(1992).

RIKEN Accel. Prog. Rep. 26 (1992)

V -2-4. Effects of Ground Tremor on the Orbit Distortion ofSPring-8 Storage Ring
H. Tanaka and A. Ando
To obtain highly brilliant photons emitted bycirculating beams, it is important to reduce
practical emittance. This emittance can becalculated with the photon density on a sample
averaged through an experimental period. Whentime-dependent orbit modulation occurs and its
frequency is large enough, the practical emi ttanceincreases and it is approximately expressed as a
convolutional form:
Etotal z-E z = L\Ez = 2.
Ez
Ez

V zz+ zz'
Evib
E

Evib
E

z=x Y

"

(1)

where Evib represents emittance of the orbit
modulation and subscripts x and y represent a
horizontal and a vertical plane, respectively. In
order to estimate the emittance growth due toground tremor, we investigate its effects on theorbit distortion.
Plane ground wave model l ) is used here. In thismodel, we assume the following; (1) the ground
tremor is decomposed into plane waves, (2) thewaves propagate straight and with a constantvelocity, (3) the waves are uniformly distributedon the surface and cover the ring completely, (4) aring is regarded as a circle, and (5) magnets along
the ring oscillate synchronizing with the waves.
Schematic figure for the model is shown in Fig. 1.

position, and a mean radius of a ring,
respectively. We introduce a parameter L\cj) torepresent the phase-difference from the center ofthe ring. At the position en, L\cj)(en, ew) is writtenas

K·r = IKj· R .cos{en - ew},
ro·R
cos(
}
=--'
en-ew,

L\ q{ en,ew} =where ro and Vt are an angular frequency and a
propagation velocity of the wave, respectively.
Therefore, the transverse displacement due to thewave at en is expressed with L\cj)( en, ew) as
L\xn = A· cos{en - ew).Ret exp i{ rot + L\ <I( en,ew) + cj)o }],L\Yn = A .Re{exp i{ rot + L\q{en,ew) + cpo }] •

(3)
(4)

In the above, L\xn' L\Yn, A, and cj)o are ahorizontal and a vertical displacement at en, an
amplitude of the wave, and an initial phase of
the oscillation, respectively. Equations (3) and(4) are substituted into well known formulae 2) fora closed orbit distortion and then they are
averaged on the initial phase cj)o and theamplitude A. We obtain normalized
amplification factors Fz as

F~ =(E~ib j =1

L L t~zi·t~zj(A 2)
16sin 1tV z i j(B'L\' (B'L).
. __}l . --~ . COS (Jlz; - Jlzj}A.{ COS(L\cj){el,eW})
Bp
Bp. cos l L\ <I( 9j,ew}} + sin (L\ cj){ ei,ew }} sin (L\ cj){ ej,ew)) } ,Reference

wave1f(A=

Vector lC

Ring

(2)

Vl

~ }Magnets

Fig. 1. Schematic geometry described by the model.

In the figure, ew, en, and R denote a direction ofwave-propagation, an arbitrary azimuthalcos(ei - 9w} ·cos{ej - ew) at z = x

I

1 at z = y,(5)where Vz, Jlz, B'L, and Bp denote a tune andphase advance of a betatron oscillation,
integrated strength of a quadrupole magnet, andmagnet rigidity, respectively. The angle bracket
represents the ensemble mean of a parameterwithin it. For a Chasman Green lattice which iscomplicated compared with an FODO lattice, eq.
(5) cannot be written with a series of Bessel
functions used in Ref. 1.

-15)-

In the following calculation, a propagation
velocity is assumed to be 1000 m/ sec on the basisof the data measured at Harima Science Garden
Ci ty. 3) The amplification factors are also
calculated at the center of the high ~ straightsection. In Fig. 2, we show the dependence of thenormalized amplification factors on the frequencyof the wave. From these results, we see

incidence of the wave. Since a resonant peak isobserved at 10.... 13 Hz in the power spectrum of themeasured data,3) the frequency of the wave isfixed at 13 Hz. We see that the horizontal(a)9•••••••.•••••••

t................. t................. t.......

I ! I. ·......······r······························r·········
3.•..•.•....

_.r-.. _. . ,Incident Angle [deg.}...

°0~~.L~~~4~0~~~6~0~~~~~~

,g

(b)

C"I

~

Frequency [Hz]

2.6

c

-S

.~
&..

12

····~~······t···..·. ·········t··········..·····I..··············..1·..······..·····

10............... 4:................. ~: ................. :: ..................:~...... •••••••

o

~

:

:
:

:

:
:

:

:
:

~

:

~
G.I

:
:

.!::!
C;

~

...

i

Z

200

:........................ .
~~:Incident Angle [deg.]·..r..·....·..· ........... l· . . . . . ·

: :

.

2.0

E
o

· . ·. · ·. ·. l. · . · ·. ·. ···r··..·············!'·······..···.... ..........

................................. c. ..............

2.4

lEC.M
.e
E ....
< t: 2.2....·..·....·..,......···..·..·..r· ..·..·····..····r·················;...........
4~

Fig. 3. Normalized amplification factors versus theincident angle. The frequency is 13 Hz. (a) and(b) show the horizontal and the verticaldependence, respectively.

Frequency [Hz]Fig. 2. Normalized amplification factors versus thefrequency of the wave. The incident angle is set
to be 0.0 degree. (a) and (b) show thehorizontal and the vertical dependences,respectively.

the following: (1) The normalized amplification
factors are at most .... 10 in the regime tha t thefrequency is less than 100 Hz. (2) The orbit
distortion is not induced in both planes in theregime that the frequency is less than .... 10 Hz. In
this regime, the wave-length is so large that theoscillations of all magnets within a few straightsections have almost the same oscillation phases.
This cancels out the contributions to COD fromeach magnet.
In Fig. 3, we show the dependence of thenormalized amplification factors on the angle ofamplification factor strongly depends on theincident angle in this frequency regime, but it is
not beyond 0.4 .
According to the measured da ta, the peak
amplitude at 10.... 13 Hz is about 10-3 Jlm. By using
this value and the calculation results, evib z isestimated to be less than .... lxl0- 17 and dex anddey are 0.01 % and 0.1 %, respectively. We findthat the emittance growth due to the ground
tremor is small in the storage ring of SPring-8.
References
1)

2)
3)

-152-

J. Rossbach: Particle Accelerators, 23 , 121 (1988).
E. D. Courant and H. S. Snyder: Annals of Physics,
3,1 (1958).
Conceptual Design Report, SPring-8 Project Part I
Facility Design 1991 [REVISED], JAERI-RIKEN
SPring-8 Project Team.

RIKEN Accel. Prog. Rep . 26 (1992)

V -2-5. Geodesy for the Storage Ring of SPring-8
S.Matsui and I.Takeshita
The
SPring-8
surrounds
MiharaKurriyama Hill which is 50 m higher
than the storage ring level. Ten geodetic
points (SR l-SR 10) are posi tioned outside
the ring as shown in Fig.I. The style,which is a Japanese standard fiducial
point, is shown in Fig.2.

Figure 3 shows one of the 23
monuments for the magnet alignment on
the ring and the cross section of thetunnel.
This concrete block is fixed byanchor bolts to preyent it from shifting.

SR 6

Fig.3.

A monument for magnet alignment.

S R 8 L4---4t1lf,.HIJ'LJ j

SR I 0Fig. 1.

oThese monuments can be used not only
for the magnet alignment but also as a
mark
for
the
constructionof theaccurate wall of the tunnel.
It is possible to align the magnet even if
the number of monuments is reduced.
However the accuracy becomes better as
the number of monuments is increased,
and a 60 m interval between twomonuments is adequate for measuring
the distance with ease between themonument and the wall.
If the interval
is 120 m, it is hard to measure thedistance from the monument to the wallwhen the tunnel is constructed.
A stand for survey instruments ismounted on themonument asshown in FigA.
The measurement
becomes easy andaccurate by using
these stands.

200m

Surface network.

FigA. A stand forsurvey instruments.
Fig.2.

Geodetic point outside the ring.

A weak point is that it is hard to connect
these points with triangles because of
the Hill.

The distance is measured by a Kern
Mekometer ME5000 (measuring accuracy
0.2mm+0.2ppm) and the angle by a Wild
11
Theodolite T3000 (accuracy 0.5 ).

- 153-

RIKEN Accel. Prog. Rep. 26 (1992)

V -2-6. Status of SPring-8 Magnet System
J. Ohnishi, N. Kumagai, S. Motonaga, S. Matsui, H. Takebe,and K. Kumagai
Prior to the mass production of about nine
hundreds magnets of the SPring-8 storage ring, adipole, two quadrupole, and a sextupole havebeen fabricated and delivered to our laboratory.
There was no great problem for their fabrication
except only one quadrupole that did not satisfy
the required dimensional accuracy. It had large
asymmetrical yokes and was not strong
structurally. The same type of quadrupoles will
be changed a little in the design of yoke supports.
We measured their magnetic characteristics suchas excitation curves, magnetic lengths, andmultipole field components. The dipole magnet
was measured with a hall probe, the quadrupoles
with twin search coils and harmonic coils, andthe sextupole with the. harmonic coils with arotary encoder. 1,2)
Table 1 lists the measured coefficients ofmultipole fields. Those of the dipole and the

sextupole magnet were smaller than the tolerance
limits required by the beam dynamics. However,the strength of the dodecapole field 'of thequadrupole magnet was larger than therequirement, though that had been predicted.
This component will be corrected by attaching
shims to the end pIa tes of the magnets. Moreover,since other components of the quadrupole magnet
were slightly large due to the fabrication
inaccuracy, it is necessary to check the influenceon the beam by the tracking simulations.
Presently, mass production of the storage ringmagnets has begun and a few ten magnets arecompleted. By next spring, thirteen dipoles, abouta hundred quadrupoles, and a hundred sextupoles
will be delivered to the construction site of thestorage ring. We will start to make a series ofmeasurements of all the delivered magnets inorder to confirm their magnetic characteristics.

Table 1. Multipole field strengths of the fabricated magnets ..
multipole

dipolequadrupole

sextupole

octupole

dccapole

dclciccaJX)le14-polc

16-pole18-pole30-pole

n

0

1

2

3

4

5

6

7

8

14

1.5x10 1

3.1x10 1

2.0x10

1.6

4.7x107.1xlO- 2 1.1x 10-4 -2.8xlO- 2 -4. Ix 10- 2

BM

b

Q\1

:an+ib n:

2.3xlO- 1 1.7xlO- 3 7.5xl0- 2

b

2.4

SM

n

n

an

4

-3.8x104-1.2x 1072

5.0x10- 2 5.0x 10-2

8.1

4.5x102.2xlO-2 2.5x 10- 1

3.2

5.6x101
1

3.8x103

3.2xl031.2x101.1x106
5

2.8x107.7x10

15
12

notation:

BL-I, (bn+ian)(x+iy)nBp n
condition of measurements:
BM:Bo=O.679 [T], L=2.804 [m], QM:B'=17.4 [Tim], L=O.3S4 [m], SM:B"=420 [T 1m2], L=0.30 [rn](1992).
2) J. Ohnishi and N. Kumagai: This report,

References
1) J. Ohnishi, H. Takebe, K. Kumagai, and
S. Motonaga: IEEE Magnetics, 28, 1, 546

p.155.

-154-

RIKEN Accel. Prog. Rep. 26 (1992)

V -2-7. Magnetic Field Measurements with Improved Harmonic Coils

J. Ohnishi and N. Kumagai
All the magnets of the SPring-B storage ring will
be inspected by field measurements before theinstallation in the ring. In the field measurements
we measure excitation curves, magnetic field
lengths, multipole fields, and positions of themagnetic center. We will use a field measurement
device called harmonic coils in order to makeprecise measurements in short time.
Figure I shows a schematic view of the harmonic
coils. When they are rotated in quadrupole or
sextupole magnets, harmonic voltages are
generated proportional to multi pole fields. In thefirst system, the induced voltages were directly

analyzed with FFT. However, since induced
voltages are influenced by the angular velocity of
the coils, it is difficult to measure the fieldstrengths and the multipole field coefficients
precisely.
Then, we attached a rotary encoder to theharmonic coil, and integrated voltages at regularintervals of rotating angle. Because theintegrated voltages are independent of theangular veloci ty of the coils, we can measure thefield strengths with the accuracy of about 1 x 10-4
and the multipoles stably.
Moreover themeasurements of the rotating angles enabled us to
Motor

FRP Bobbin
Slip Ring, , ,..,, ... Short Coil(I

Long Coil-----------------------------,"Long Coil: w40 x L 1500, 1turnShoTt Coil: w35.5 x L20, 50turns
Fig. 1.

Schematic view of the harmonic coil.

decompose each multipole field into a normal anda skew component.
Figure 2 shows multipole field strengths of thefirst fabricated magnet of 336 sextupoles as an
example. Black and white bars indicate a normal
and a skew components for each multipole field
respectively. The strengths of multipole fields
are represented at a point on the circle with aradius of 35 mm by a unit of gauss. It is found fromthe figure that a normal component is dominant
for the 18-pole (n=9) and the 3D-pole (n=15)
components because of the geometric symmetry of
the magnet. The quadrupole and the 28-polecomponents are induced from the sextupole andthe 3D-pole respectively by the displacement
between the magnetic center and the rotating
center of the harmonic coil.
Series measurements of the storage ring magnets
with the harmonic coils described above will
start in spring next year.

-155-

10000

_

•

1000

E
E

0

l£l

~

100 t--

nonnal _
skew

--

L..

e

10 t--

til

..c

eJ,
cc;J
L..

r.r;

.1

.01

I III

~

l-

~ I II

1 2 3 4 5 6 7 8 91011121314151617181920

Harmonics

Fig. 2. Multipole field strengths of the first
fabricated sextupole magnet measured withthe harmonic coils.

RIKEN Accel. Prog. Rep. 26 (1992)

V -2-8. Design of Injection Section for the SPring-8 Storage Ring
K. Kumagai and S. Matsui
Detailed design of the injection section for the
SPring-8 storage ring is in progress. The beam fromthe synchrotron is injected into the storage ring at
one of the straight sections through three DC
septum magnets (SEPS,SEP6, and SEP7) and apulsed septum magnet (SEP8). These magnets are
required to provide about 8.4 degree deflection to
the injection beam, while not disturbing thestored beam. Figure 1. shows the arrangement of
the septum magnets.

Fig.l. Arrangement of the injection section.

The main parameters of DC septum magnets arelisted in Table -1. SEPS, SEP6, and SEP7 are
excited in series by the DC power supply, andoperated in air with a stainless steel vacuum
chamber passing through the magnet gap. Thesemagnets have straight axes, and the cores of SEP6
and SEP7 have the same cross section to save theconstruction cost.

magnetic field and is also a part of the storage
ring vacuum chamber. The magnet core of SEP8 islaminated plates of 0.1 mm thick silicon steel.
Eddy Current Screen (Cu)Storage Ring
VactJum Chamber(Magnetic Stainless)\

Table 1. Parameters of the DC septum magnets.

Core Length(m)Bending Angle (mrad)
Peak Field (T)Number of Turns
Peak Current (A)Stability (%)

SEP5

SEP6

SEP7

1.25
65.9
1.406
10
2240
0.01

1.0
42.2
1.125
6
2240
0.01

0.5
14.1
0.75
4
2240
0.01

Single Turn Conductors/

Fig.2. Cross sectional view of the pulsed septum
magnet, SEP8.

SEP8 is a pulsed septum magnet. The crosssection is shown in Fig.2 and the parameters are
given in Table.2. The magnetic field in the gap isgenerated by a single tum conductor wound aroundthe return yoke, and it is excited by a half sine
wave pulse of current.
The septum wall has a thickness of 9.5 mm,
reducing to 1.5 mm at the injection point. Thiswall is made of a copper plate combined outsidewith a magnetic stainless. The copper plate iseffective as an eddy current screen while themagnetic stainless is effective for shielding theTable 2. Parameters of the pulsed septum magnet.
SEPS
Core Length (m)Bending Angle (mrad)
Peak Field m
Number of Turns
Peak Current (A)Pulse Width (Jlsec)
Stability (%)

-156-

1.2
24.7

0.55
1
3510
30
0.1

RIKEN Accel. Prog. Rep. 26 (1992)

V -2-9. Power Supply System for SPring-8 Magnet
H. Takebe, N .Kumagai, J.Ohnishi, K.Kumagai, S.Matsui, and S.Motonaga
A detailed design of the power supply (PS)system for the SPring-8 Storage Ring wascompleted this Summer. Based on the excitation
measurement using the R&D magnets(B, Q, andSx), their maximum currents were decided. All
the big PSs are loca ted in PS-room A, and steeringand auxiliary (QA-) PSsl) are located in PSrooms A, B, C, and D. Connecting cables between
the PS and magnets are designed to have a current
density under 1.2 A/mm 2. The maximum voltages
are also fixed.
The maximum current, voltage, power andcubicle number for the B-PS are 1270A, 1157V,
1515kW, and I, respectively. Those for Q
magnets are 392A - 570A, 480 ;. 1281 V, 192 728kW and 10. And those for Sx magnets are
300A, 669 - 781V, 201 - 234 kW and 7. Total
inductances of the B,Q, SX magnets over 48 cells
are 0.76 H, 0.45 - 1.25 H, and 0.62-0.72 H,
respecti vely.

Each steering magnet(St) is connected to one PSof 5 A and 51 V. Total number of the St-PS is 192.
Thirty-six sets of St-PS are mounted in 1 cubicle
and are supplied a DC bus together.
The Bending-magnet-PS has an input transformer for 6.6kV, 24th phase thyrister diodes
and a passive filter system.
Figure 1 shows a block diagram of the Q-PS
system. Input voltage for the Q-PS is 400 V. It has
12th phase thyrister diodes and a reactor
transformer active filter system. Input
transformer phases of the Q-PSs are shifted forhalf sets in order to reduce the harmonic current
distortion. QP-2,5,6,9 have bypass (2%) circuits tocompensate a small difference of the excitation
factors caused by the magnet yoke shapedifference. Q magnets in the long straightsections can be compensated by an auxiHary power
supply system(QA-PS). They (40 sets. initially)are 11-17 A and 19-33 V floating PSs.

O.5mH

O.2mH

570A
770V

..

::

To
M.,DClOC -CT

CB
\.

~8---

200V
Input

VME
Master RIO

ActivcFilter PS

StatusCB

I

Optical Fiber

Fig. 1. Block diagram of the Q PS.

Input voltage of the Sx-PS is 400 V. A six phasethyrister diode system is stacked with a 30 kHz
switching regulator system. Input voltage of the
St-PS is 200 V and a 100 kHz switching regulator
system is used. Thirty-six sets of St-PSs aremounted in one cubicle. An RIO star branch isconnected to 36 RIO cards of type-A~ '2)1One RIO-A
card controls the DC bus in the cubicle.
B-, Q-, and Sx-PSs are controlled by the RIO
type-B. The current conlJol data are given by a 16
bits parallel 1/03). QA and St-PSs are controlled

by the RIO type-A and the current control signal
is given by an analog voltage of the RIO-A. The
shunt voltage of the St and QA PS is directly
connected to the RIO's ADC inputs buffer
amplifier.
References
1) SPring-8 Project, 1,2-68 (1991).

2) H.Takebe et al.: This Report, p. 176.
3) H.Takebe et al. : RIKEN Accel. Prog. Rep. 25, 209,
(1991).

-157-

RIKEN Accel. Prog. Rep. 26 (1992)

V -2-10. High Power Test Results of a Prototype Single-cell Cavity
for the SPring-8 Storage Ring
K.Inoue, H.Ego, Y. Ohashi, Y.Kawashima, H.Suzuki, * H. Yonehara, *I.Takeshita, and M.Hara
Two single-cell prototype cavities for the SPring-8
storage ring were fabricated with different methods,
which were a diffusion bonding (type A) and an electron
beam welding (type B) 1). Both cavities were made ofoxygen free high conductivity copper(OFHC) class 1.
These two cavities have been tested independently.
In the fIrst step, vacuum pressure test was done. Only
a turbo molecular pump of which pumping speed is 200
Vsee was operated during baking at 150°C for 24 hours.
After then, a sputter ion pump with the pumping speedof 140 Usee was operated. Obtained minimum vacuum
pressure was 7.5¥10-8 Pa through such a procedure. As
to vacuum pressure of both single-cell cavities, theirvalues were almost the same. No difference depending
upon the fabrication methods was observed, but thepressure was only dependent on the outgases from thesurface of materials.
In the second step, RF high power loading test ofthese two prototype cavities has been done at I-MW
klystron test stand 2). After the RF equipments, an
input coupler, an adjustable tuner, two fixed tuners, a
pick-up probe and a turbo molecular pump of which
pumping speed is 300 Usec, were fully assembled, a
CW RF power within a few kirowatts has been fed tothe cavity for several hours in order to condition the
inner surface of the cavity. As an RF input coupler, acylindrical ceramic RF window which was developed for
KEK TRISTAN MR, used for the same frequency
508.58 MHz as SPring-8 storage ring RF system, wasadopted 3). At the beginning of the conditioning
procedure, the vacuum pressure of the cavity often got
higher. The operation was stopped until the vacuum
pressure was recovered below the threshold level which
was set at an interlock system. The recovering time ofthe vacuum pressure got shorter and shorter as*JAERI SPring-8 design team.

-158 -

conditioning proceeded. After enough conditioning, RF
input power has gradually been increased to 100 kW inabout 24 hours. In order to cool down the cavity in ahigh power test, pure water of which flow rate is 150
Vmin was supplied to the cooling water channels of thecavity. Two single-cell cavities showed different
temperature rises. The conditions were as follows; RF
input power was fixed at 50 kW and input watertemperature was 33°C. The temperatures of these twocavities were measured by thermocouples at the sameplaces and obtained 45 °C for the type Band 41°C for
the type A. Water channels of type A are located nearer
the inner surface of the cavity than those of the type B.
The place of the highest temperature was at the port ofpick-up probe because no water channels were there.
A different input coupler whose ceramic window wasof a disk type has been developed 4). The coupler was
designed to have a power limit of 100 kW for the
single-cell cavity. But, in a high power test,
temperature rise at the ceramic window was steeper than
expected. The input coupler with disk type windows isunder the development.
References
1) K.Inoue, T.Nakamura, Y.Kawashima and M.Hara,
IEEE Par. Ace. Conf.,San Francisco, (1991) 667.
2) K.Inoue, Y.Kawashima, T.Nakamura, and M.Hara:
RIKEN Accel. Prog. Rep. 24 166 (1990).
3) M.Akemoto and Y .Yamazaki, Proc. of the 7th
Symp. Accel. Scien. and Tech., Osaka Japan (1989).
106 .
4) K.Inoue, T.Kusaka, H.Suzuki, T.Kojo, H.Ego,
Y.Ohashi, Y.Kawashima, and M.Hara: RIKEN
Acce!. Prog. Rep. 25 212 (1991).

RIKEN Accel. Prog. Rep . 26 (1992)

V -2-11. Higher Order Modes of Single Cell Cavities

for the SPring-8
H. Ego, M. Hara, K. Inoue, Y. Kawashima, Y. Ohashi,
H. Suzuki, * I. Takeshita, and H. Yonehara*
For a storage ring of the SPring-8, it is mostimportant to accumulate an intensive electron beam
having a low emittance in order to obtain a highbrilliance photon beam. The beam quality is strongly
dependent on beam instabilities. As frequencies of aparasitic higher order mode (HOM) of RF cavities are.multiples of a revolution frequency, the coupled-bunch
instabilities grow up and induce beam blow-upl). A
bell-shaped single cell cavity is favorable for a storage
ring since transverse and longitudinal HOM impedancesof the cavity are smaller than those of a normal reentrant cavity2). Then HOMs must be studied in detailto obtain the stable and low emittance beam. On
account of limited space, this report describes the
TMII0 mode which has a large transverse impedance.
The bead perturbation measurements3) have been
executed to specify HaMs in the cavity. Various typesof beads were used. Then directions and distribution of
the electric and magnetic fields of HaMs weredetennined.

that of the 761MHz modes does smaller. On the other
hand, the vertical change of the tuner position causes alarge shift for the 761MHz mode and a small shift forthe 761MHz mode.

.
<a)
2

.
D 761MHz• 765MHz

....

",.

.

~.-.

'

.

••
•••

.
.
.
..
.
..
..
..
.
'
..

o~maum~~~Dtt~~

-15

-10

-5

0

5

10

15

position [nun](b)a V761MHz• V765MHz

2

1.0..-___......_ _ _--..,,....-....-_ _ _ _- . ,

.r

0.5

~o

o

...!

-15

-10

-5

0

5

position [nun]position [em]Fig.l. Frequency shifts by perturbation of a metallic plane
directed vertically.

The TMII0 mode frequency was calculated withcomputer codes 2). In a real cavity, however, thedegenerating TMII0 mode splits into two modes .
Figure 1 shows frequency shifts by perturbation of ametallic rectangular planes directed vertically and on abeam axis. This indicates that the direction of themagnetic field of the 761MHz mode across the axis ishorizontal and that of the 765MHz mode is vertical.
To suppress instabilites4 ), it is effective to move theHaMs frequencies without changing the accelerating
mode (TMOI0) frequency. Figure 2 shows frequency
shifts of the TMII0 mode as a function of tuner
position. The frequency of the 765MHz mode becomeslarger as a horizontal tuner is put into the cavity, but• Japan Atomic Energy Research Institu~.

- 159-

Fig.2.A frequency shift by (a) a horizontal tuner and(b) a vertical tuner

An about IMHz shift in TM 11 0 mode could be madeby small modification of the cavity size. In this case,however, the frequency of the accelerating mode of thesecavities is adjusted to 508.88MHz by tuners.
With frequency tuners and a small change of the cavity
size, HOM's frequencies, at least TMII0 mode
frequencies, can be adjusted not to meet conditions of
the coupled-bunch instabilities.

References
1) H.Kobayakawa, Y.Yamazaki, Y.Kamiya and M.Kihara,
Jap. Jour. App. Phys. 2S 864 (1986)
2) K.Inoue, T.Nakamura, Y.Kawashima and M.Hara, IEEE
Par. Aceel. Conf., San Francisco 667 (1991)
3) L.C.Maier,Jr. and J.e.Slater, Jour. App. Phys. 23, 68(1952)
4) H.Kobayakawa, M.lzawa, S.Sakanaka and S.Tokumoto,
Rev.Sci.Instrum. 60 (7), (1989) .

RIKEN Accel. Prog. Rep. 26 (1992)

V -2-12. Impedance Estimation of the SPring-8 Storage Ring
T. Nakamura
The broad band longitudinal impedance of thevacuum chamber of the SPring-8 storage ring wasestimated assuming cylindrical symmetry.
Analytical equations and results of thesimulation with MAFIA T2 are used, some of theanalytical equations are derived to approximate
the results of simulationsl -3 ) (pair of shallow

transitions) and the others are derived
theoretically4,5)(cavity, gap, slot, resistive wall,synchrotron radiation). In the simulation with
MAFIA T2 6), several model shapes of wake
functions 2,3)(inductive, resistive, cavitylike) are
assumed to fit the results. The result is shown in
Table 1.

Table 1 - Impedances of the components of the vacuum chamber of the SP ring-8 storage rmg.
single?:11

Number

n [0]

total

?:11

n [0]

Equations

MAFIA T2

Equations

MAFIA T2

RF cavities

4.8xl0 ~~4.0xl0 ~~32

1.5xl0 ~~1.3xl0 ~~weldments-2.6xlO-6 i-3.1xlO- 6 i

2000-0.005 i-0.006 iflanges--7.8xlO- 6 i

700-0.005 i-0.005 i

offsets-4.9xl0- 6 i-7.2xlO-6 i

2700-0.013 i

300--0.019 i
3QQ.

-3xl0-4 i

40-0.012 i-

6000-0.018 i
72 .
--1

3

-

BPMs
ID sections
pumping slots-4.6xl0-4 i- 0.012 i
n

5

3

12.
n

n

5

n

-

transitions at RF-0.0013 i-0.0016 i

4-0.005 i-0.006 iabsorbers at RF-6xl0-4 i-7xlO- 4 i

12-0.007 i-0.008 i--lxlO-4 i

400--0.040 i

-

100

-

- 0.3 in-600-(0.003+0.2/n) i20+ n-l8Q.in-resisti ve wall

-

-

-

1.9 (~)-

synchrotron radiation

-

-

-

0.026

-

bellows
valves-(2.7xlO- 5+0.002/n) i +0~2

steps in antechambers

The total impedance is expressed as?:11 = 1.9 (I-i) + 1.5xl05 (l+i) + (3.8-2.5i)XI0 2 + 0.03 - 0.11 i
n
rn
nrn
n
Here n is (j) / (j)rev, (j)rev is the revolution
References
1) K. L. F. Bane, S~AC-PUB-5177 (1990).
frequency, and i is fi. The frequency (j) where the.
. .. . .
.
2) M. Takao, T. HlgO and K. L. F. Bane, Proc. of the 1991
Instablhhes will o~cur IS expected to be hIgher
IEEE Particle Accelerator Conference, San
than c/a, where a IS the r.m.s. bunch
F'
1991 , p. 506 .
. length. " and c
ranCISCO,
3) S. Heifets, SLACj AP-93 (1992).
is the speed of light. Hence n IS greater than
23000. The absolute value of total impedance4) R. L. Gluckstern, Phys. Rev. D ~ p. 2773(1989).
IZtt/nl· -0130
5) S . Heifets, SLAC-PUB-5792 (1992).
IS .
.
6) R. Klatt and T. Weiland, Proc. of Linear Acc elerator
Confference, SLAC, 1986, p.282.

-160-

RIKEN Accel. Prog. Rep. 26 (1992)

V -2-13. Design of Aluminum Alloy Conflat Flange for SPring-8
Storage Ring
Y.Yanagi, K.Shibuya, M.Tsuchiya, S.Yokouchi,
H.A.Sakaue, K.Watanabe and S.H.Be
Conflat type flanges are uSed as vacuum
chamber joints of the Spring-8 storage ring. The
flange materials are shown in Table 1. The
aluminum alloy A2219-T852 is suitable for theflanges because of the high hardness and the good
welding compatibility with the chambermaterial A6063-T5.
In view of the flange-flange interface, theSPring-8 conflat flanges are classified into thefollowing groups: AI/ AI(aluminum to aluminium
confla t flange) ,AI/SUS and SUS / SUS.
An AI(AlOSOH24) gasket is mounted in AI/ Al
flanges. A Cu(OFHC) gasket is mounted in
SUS/SUS flanges. As for the gasket in AI/SUS
flanges, an Al gasket is chosen because of easy
deformation with the assembling torque. The
surfaces of bolts, nuts and washers are coatedwith alumite, solid film lubricant and hardalumite respectively to reduce the bolt/nut

IIdepth . ""-.

RF contact

Fig.1. RF contacts assembling method.

Table 2. RF contacts specification.
Table 1 . Flange materials.
Al flange

SUS flangematerial

A2219-T852

SUS304L

sarfacefinishRmax 1.6

manufacturer's
standard

hardness>120HV'">400HV "'-It

manufacturer's
standard'" Hardness without TiC coating'" If- Hardness with TiC (> 1 Jl.m) coatinggascket, bolt and washer
AI/AI

AI/SUSSUS/SUSgasketA1050H24

A1050H24

Cu(OFHC)

bolt

A2024-T4

A2024-T4

SUS304nut

A6061-T6

A6061-T6

SUS304

washerA2017-T4

A2017-T4

SUS304material

Be-Cu (JISC1720 P-1/4HT)
design target 0 contact fouce >50 go surface stress <85kg/ mm2

friction.
To minimize the RF impedance caused byabrupt changes in the cross section of the vacuum
chamber, we use RF contact fingers to bridge the
3.5 mm gap of the gasket groove.
The cross section view of the flanges with RFcontacts is shown in Fig.1 and the requirement to
the RF contacts is summarized in Table 2.
In the design of RF contacts the following
attention has been payed:The gap and depth of
RF contacts are to be kept as small as possible,
while to ensure mechanical performance thefollowing criteria must be satisfied:(1) The surface stress of RF contacts should belower than the spring limit stress(8Skg/mm2)(2) The minimum contact force is more than 50 g
to reduce the electrical resistance on the contact
surfaces.
A test for comfirming these requirements by themeasurement of the contact force and the surface
resistance is planned to be made in Nov,'92-161-

RIKEN Accel. Prog. Rep. 26 (1992)

V -2-14. Sealing Performance of AL/SUS Conflat Flanges
K. Shibuya,* H.A. Sakaue, K. Watanabe, S. Yokouchi, and S.H. Be
We experimentally investigated the reliability of leak tightness for multiple extreme
operations in baking combination flanges ofdifferent metals such as AL-alloy and SUS(stainless steel). The leakage is usually caused by
the relaxation of tightening force during baking.
Table 1 shows the specification of materials usedin this investigation.
Table 1. Main specification.

CoverfrangeA 2219 - T852

ChamberfrangeSUS 304

GasketA 1050 - H 24

Bolt
Nut
Washer

A 2024A 6061
A2017

200

elSa
~

)

~

100
1-0

~
E 50

~

I

/:

..

1\
\,

I
I

I

,

I
I

I
I

I
I

I

I

23

20
18 I

I

:

~------ -r----- "1----...
,
I

I

a

Tightening of flanges with bolts are as
following : Firstly, a flange is alternately
tightened at intervals of 1800 with bolts by torqueof 50kgf-cm and then by that of 90kgf-cm.
Finally,the flange is retightened in turn by thesame torque of 90 kgf-cm. A repeated baking cycleof the flange is shown in Fig. 1. Here thetightening force is defined as the load per sealing
length [kgf /mrnJ.
A leak test was done before and after baking.
Table 2 shows the size of flanges, their numbers
used in the test, and baking cycles. In all cases noleakage was detected even with the maximum
sensitivity of a leak detector. The relaxation oftightening force for the bolts during the baking isshown in Fig. 2. This figure shows that thetightening force is reduced about 30 to 40 % in theinitial 10 baking cycles, but after then, thetightening force is kept to be constant. This result
is for the flange size of ICF 253, but we think thistendency is also applied to other flange sizes (ICF
203,114,etc). This means that the leakage is notcaused by the relaxation of tightening force. At
present time, the reason for the leakage is notclear. This problem is to be pursued furthermore.

I

o

2 2.5
4 4.5
Time (hr)

E 16

6

E

~

14
~ 12
~ 10

Fig.1. Baking temperature.

~~'A

.hB.

"\..

....

'2

6

~

4

.1::

o
o

3

ICF 203

102

ICF 1146

1.~.~ .v:P--'-~~

20

-;

~

2

Flange size Baking cycles SetsICF 253~

h. _... 11111!"1 ~~8s::
Table 2. Various type of flanges used for leak test.

.~~~A>'

II{

.

. .

--"

5

10

15

.
20

25

Baking cycle
Fig.2. Relations of tightening force vs baking cycle for

an ICF 253.

* SMC Ltd.

-162-

RIKEN Accel. Prog. Rep. 26 (1992)

V -2-15. Photodesorption for OFHC-class 1
by High Energy Photon
K. Watanabe, T. Hanasaka, Y. Hirano,* H.A. Sakaue,
K. Yano, S. Yokouchi, and S.H. Be
One of main problems to be considered in thedesign and manufacturing of the vacuum system
for the SPring-8 storage ring is interactions ofsynchrotron radiation (SR) with absorbers. To
investigate the interactions we measured thephotodesorption yield of OFHC-classl ( oxygen
free copper ), the material of the absorbers, using
the high energy the photon beam (the criticalenergy 26 keY) from the Accumulation Ring (AR)of TRISTAN at KEK.
Experimental scheme is shown in Fig.l. SR was
adjusted with a collimator slit of 5mmx5mm, andperpendicularly directed onto the inner wall of
test chamber. The test chamber was a cylindricaltube of 300mrnxq,6Omm made of OFHC-classl. The
production of the test chamber is roughly as
follows; machining (oil-free) ~ brazing ~chemical cleaning (acetone, ethanol) ~ baking(10 hours at 450°C). The chamber was evacuatedand baked out about for 13 hours at 150 °C in
advance of the SR irradiation, and thereby the
final pressure, namely the background pressure forexperiments was 6.8xlO-10 Torr. The chamber wascooled with water to reduce thermal desorption
during experiments. The outgassing rate due tophotodesorption was obtained by through-putmethod.

(equivalent nitrogen pressure) at Dp of IxI0 21
photons/slit. This value is higher by about oneorder compared to the experimental results madewith the critical photon energy of 4 keY from the
2.5 GeV storage ring of Photon Factory at KEK[1].
The reason is not clear yet, and this is the
problem to be discussed further. 11 is as following:
1) Dp$;lQ2o photons/ slit
11=4xlQ-4 (molecules/photon),
2) Dp>020 photons/slit
11=1.23xl01O -Dp -2/3 (molecules/photon).
As the critical photon energy at AR isapproximately equal to that (=29 keY) at SPring8, we obtain 11 of OFHC-classl at SPring-8
assuming that 11 at SPring-8 is equal to 11 at AR:
11=1.1xlQ-4-Di-2/3 (molecules/photon),where Di (A-hours) is the electron beam dose. As aresult, the outgassing rate per 1 mrad is obtainedas
Q=3.4xl 0- 7 -Di -2/3 (Torr-II sec).
For example, if Di =100 A-hours, we obtain
Q=1.6xl0- 8 Torr-l/sec/mrad. Further we areplanning experiments of elucidation of thephotodesorption mechanism.

.

16757.2mm from source point - - - _. .~:ionization gauge ionization gauge(lG-2)"""(lG-1)-5

synchrotron
radiation
sputter ion turbo molecular
pump
pump

,

10 18
10
quadrupole mass
spectrometer

Fig. 1. Schematic drawing of the photon beam line(NE9).

Figure 2 shows the relation between thephotodesorption yield (11) and photon dose (Dp).
11 is reduced to 1.3x 1 0- 4 molecules/photon

19

10Photon Dose (photons/slit)

Fig.2. Photodesorption yield(equivalent nitrogen pressure).

of

OFHC-c1assl

References
1) S.Ueda et aL: Vacuum, 41 No.7-9, 1928 (1990).

.. ANELVACo.

-163 -

RIKEN Accel. Prog. Rep. 26 (1992)

V -2-16. Electrical Parameters for the Operation of a Titanium
Sublimation Pump
S.Yokouchi, H.A.Sakaue, K.Watanabe, and S.H.Be
We investigated electrical parameters for theoperation of a titanium sublimation pump (TSP),
which is considered as a vacuum pump of theSPring-8 storage ring, during the performanceexperiment of a TSP.1) A sublimator of the TSP
consists of three filaments, each of which is
85% Ti-15%Mo alloy wire, 2 mm in diameter, and
200 mm in length. The filament is heated byapplying electric current directly to it from a
power supply. The experiment was continued
untill the filament cut.
Figure 1 shows the measuring system for theelectrical parameters of the TSP. The power
supply has a dropping characteristics so as tosupply a stable power independent of the changeof filament resistance (Rm). The Vfil'S and Ilin' s
were measured with respect to various primaryvoltages (V pri 's) during the experiment. From the
Vfil and llin, we also got the Rm of the filament
and the power (Pfil) to sublimate titanium.
Figure 2 shows variations of the Rfil and Pfil

during the experiment. The Rfil increases with therunning time since the filament becomes thinnerowing to sublimation of titanium. Although the
Rfil must depend on the Vpri because of thedependence of the filament temperature on the
P fil, we cannot find the tendency in thisfigure.lnitial PHI at V pri = 200 V is a little
smaller than 270 . W, which is recommended as
the power for normal operation by the
manufacturer. The Pfil gradually decreases withthe running time, and finally becomes to 80% of
the initial value. This suggests that we should
use such a power supply as can supply a power
more stably than the present one in the real ring.
From the result, one filament can be opreated forabout 90 hours, but we have not investigated how
long the filament, whose diameter gradually
becomes thinner, can give a sufficient pumping
speed. This is a problem to be investigated fromnow.

Power Supply

~

~

CNS

on

IIin

200

+++++I---+-+---+--+~~-t--+--+--t 0.2 E+

I-lI't411-r1+- + - t - ·· -:0(I

Signal Converter

Recorder

U-I

~~

I
i: i
i

-+--J--

I!-1---- o. a:.~J--t +Thm't-r-5)

+

~

,

.

--

-10

60

ell

:

,I

I

20

I

puwer (W)

0.0

SO

100

R u nning T i me ( hou r)
Filament

Fig. 1. Schematic diagram of the measuring system forthe electrical parameters of the TSP. Vfil is thevoltage applied to the filament, Vlin the voltage dropin the current feed line, and Ilin the electric current
flowing through the filament. The Ilin can be got fromthe Vlin by using the relation between Ilin and Vlin
measured previously. The Vfil and Vlin are converted
to DC voltage with t~e signal converter.

Fig. 2. Rm and P fil vs running time of the TSP during theexperiment. Operating conditions in each stage (1)(11) are as follows. (1),(4) : Vpri = 100 V,continuously.
(2),(5) : Vpri = 150 V,continuously. (3),(6),(7),(10),(11) :Vpri = 200 V,continuously. (8),(9) : Vpri= 200 V for 30
sec, 0 V for 60 sec, alternatively.
References
1) H.A.Sakaue et a1.: This report, p.165.

-164 -

RIKEN Accel. Prog. Rep. 26 (1992)

V -2-17. The Outgassing Characteristics of Titanium
Sublimation Pump
H. 'A. Sakaue, S. Yokouchi, K. Watanabe, and S. H. Be
In the experimental beam line absorber systemof the SPring-8 storage ring, titanium sublimation
pumps (TSP) will be installed. A TSP has aproblem of outgassing at the sublimation oftitanium. In case of using a TSP at the ultla highvacuum, it is important to degass by the initialpassage of an electric current. Therefore wemeasured the outgassing rates and observed the
behavior of various molecules which werereleased from a titanium filament when thefilament was heated.
Figure 1 shows the experimental setup formeasuring the outgassing characteristics of a TSP.
The titanium filament is installed in chamber 1.
A BA gauge (BAG1) and a quadrupole mass
spectrometer in chamber 2, a BA gauge (BAG2)
and a turbo-molecular pump (TMP)' in chamber 3
CCG

QM S

~

@

11T -T IIU'~,I ,-,jd

Fore pUmp

tlJl
~11'~
W rrl
TM'

LV

XI

Ti Filament

r"
t
E:9

.50<1fi"

Chamber3~ . Chamber2

InI Cb:;;-e~lVFll

I I@ BAGI

BAG2

P2

PI

IIAGI.2 : Bayard.Alpert J:l'uJ:e
QMS: Quadrupole mass
spectrometer

CeG
TMP
LV

: Cold calhode J:puJ:e: Turbo·molecular pump
: Leak valve

are installed. The outgassing rate Q of a TSP was
obtained from Q=C(P1-P2), where P1 is thepressure of the chamber 2, P2 that of the chamber
3, and C the conductance (2.3 lis for N2) of theorifice whose diameter is Smm.
The outgassing rates and mass spectrum were
measured with respect to various primaryvoltages of a TSP power supply (V pri=100V, 1S0V,
and 200V). This experimental methods are
explained in detail elsewhere. 1 ) Measured
outgassing rates of a TSP are shown in Fig.2. The
Q increased from lxlO- 4 to 4xl0-4 Torr·lIs at thefirst heating (V pr i=100V). However, after
several heatings, the outgassing rate scarcely
increased at the same voltage, because ofdegassing of filament by several passages of anelectric current.
Figures 3 and 4 show the behavior of various
molecules (M/e=2,16,18,28,44) from the filament
at each flashing. The quantities of H20(M/e=18), CO (M/e=28) and C02 (M/e=44) weresuddenly increased at the initial heating and,after repeated heating, these quantities almost
became constant due to the heating of filament.
This phenomenon was caused by degassing offilament due to several passages of an electric
current. On the other hand, the quantities of H2(M/e=2) and CH4 (M/e=16) were always
increased at each heating of filament, becausehydrogen was released from both surface andFig. 1.
Experimental setup for measuring theperformance characteristics of TSP.

N1

10 ' I
t OOV

J

Iv

I

I

/I

UOV
I

I

JiI ..,

/

::-

:,.p

1

I

-

~

lOOV

I

~

I

lsI

I

/

{oov/

Nl

BOV

lnd

0

luk

I 0

"

0

lSI

100V

c:
lOOV

\\/

/
lOll

=
100V

I:

Jrd=

lSI

...

I

hI

QJ

/
lOOV

0

~

ln~

.~

/

=

....

/

t~~

I

til

leak

=~

t-"

I'whl

1.0

I

/

11,1,

Nl

=~

10· I

10· 1

"

M/e=18M/e=28M/e=44

I:
::l

tSl

-

/

~l Ilnlk

[ll

hI

·
··

Ink

IOOV

10 · jlnd

I::Ibi..-I-t

V
150V

lnd

\

l..o..~T~T1-r- --.....rr

I

f(

/

16'

0

10 · 4

10

51

o 50

""0 50 1«" 0 , . H"0I 50

l~OVI trdr-"050

Time(xlOOsec)/10o 50'"I

J 0

Time (hour)Fig. 2. Outgassing rate of the tltamum sublimation
pump.

Fig. 3. Variation in the pressure of major components(M/ e=18,28,and 44.) of the outgassing flux as afunction of heating time of titanium filament.

-165-

loll

-=

..

Ink

I

J

t\

,-..

10' I

1012

inside of titanium filament by heating. The
quantity of CH4 especially depended on the Vpri.
The quantity of CH4 at Vpri =100V increased
Ii ttle in comparison with other voltages. Thisphenomenon is caused by a small quantity of
sublimation of titanium, because methane isproduced with hydrogen and carbon released fromthe titanium filament during flushing of thetitanium. 2 ) However it is necessary to ascertain
the above phenomenon by the measurement of thefilament heating temperature and pumping
speed.
The outgassing of H2 and CH4 from titanium
filament cannot be negligible at each titanium
sublimation. However the other outgassing may
be sufficiently decreased by a good condition of
initial degassing of filament.

M/e=2 .::::t:: f=1=
M/e=16
~I=

.=

leak

.1

C

II\,

.ti-l.

e:

"-'

~\

t

10 ' 1

\

~

IY

<Il

-H

C
~

C

_

I

10' J

IOOY

ISOY

I

111._

III

\,

1.

~

1lOOY

~

lSi

IOOY

o 50

l'b..~

2nd
ISOY

r-'-

o 50 0 50

I\. \~~.I:: -::

2nd++ +f °rl t
2

J

0

50

"0 50

"0 50

_--j- - I--f-200Y

ltd

~o 50

Time(xlOOsec)

Fig. 4 Variation in the pressure of major components(M/ e=2 and 16)of the outgassing flux as a functionof heating time of titanium filament.

References
1) S.Yokouchi et al.:This Report,p.l64.
2) A.Roth:"Vacuum technology",North-holland
publishing company,Amsterdam p.268(1982).

-166-

RIKEN Accel. Prog . Rep. 26 (1992)

V -2-18. Reproducibility of Outgassing Rate at UHV Chamber
T. Hanasaka, K. Watanabe, S. Yokouchi, and S. H. Be
We measured the reproducibility of outgassing
rate at a UHV(Ultra High Vacuum) chamber bymeans of a so-called throughput method.
The apparatus is to measure outgassing rate of
UHV materials in a sample chamber. But only
the reproducibility of outgassing rate at an empty
chamber (the background) was described in thispaper. When we measure the outgassing rate ofsome sample pieces, we must subtract thebackground from the values measured withsamples. The measurement of background level
and its reprod ucibili ty are, therefore, very
important for the accurate measurement ofoutgassing rate.
Figure 1 shows the schematic diagram of theapparatus. The system is mainly made of SUS304
stainless steel. The surface area of the sample
chamber is 0.196 m 2. The conductance of orifice
between the sample chamber and pump sidechamber is 2.15xl0-3 m 3 /s (for N2, at 22°C). The
pumping speed of the main pump is 360l/s for N2.
The ultimate pressure at pump side chamber is of
the order of 10-8 Pa.

perature for obtaining background data.
.
(4) The baking was carried out and backgrounddata after baking were taken.
(5) The pressures of the sample and pump sidechamber (Pl and P2) and the evacuation
time were measured, then the outgassing
rate from the sample chamber at each time
was calculated by
Q=C(PI-P2) IS.
Where, Q: outgassing rate,
C: conductance between sample andpump side chamber,
PI :pressure of sample chamber,
P2:pressure of pump side chamber,
S: surface area of sample chamber.
The pressure measurement was carried out by
using calibrated BA gauges.
Figure 2 shows the influence of venting gas on
the outgassing rate. As shown, the difference
between wet air and 99 .9998 % N2 in the
reproducibility is small in our case.

- 0 - - (l)Afwr N2 vent
•
•
6

o
IE

e

•

PUMP SIDE CHAMBER(DOWN-SIDE CHAMBER)[Vcnting lime:4,lSOmin](2)( N2:97minJ(3)( N : 12,943minJ
2(4)Aflcr air vent
[Venting timc:81min](5)[Air:124minJ(6)[N :227min]2(7)[N :157min]2(8)[N 2:128min]

H

•

••

•

•

'

•

••••

• •

••

Fig. 1. Schematic diagram of experimental
apparatus.

The main procedures of the measurement wereas follows.
(1) The apparatus was vented by N2 gas.
(2) The sample inlet flange was opened for 10
min or 37 min (but no sample was installed).
(3) The apparatus was evacuated at room tem-

-167-

2
10

TIME (min)Fig. 2. Influence of venting gas and venting time on
the outgassing rate.

Figure 2 also shows the influence of venting
time (time from the start of vent to the start ofnext evacuation) on the outgassing rate.
Figure 3 shows the effect of exposure time (timefrom the opening of sample inlet flange to its
closing) on the outgassing rate.

N8 (10min)
N9 (10mln)
Nll(lOmln)...
N13(lOmln)
N14(lOmln)---R9-- N16(lOmln)
G
N18(lOmln)
A
N19(37mln)- 0 - - N20(37mln)-----&-- N23(37mln)EB
N24(37mln)- - - 0 - N26(37min))(
N27(lOmin)I
N29(lOmin)

I;

-

o

--

N

E 10. 5
( I)

ff')

E

(U

~
~

- 0 - - l~~xposure

2 hxposurc
3 Exposure

time:l0min
time:l0min

64~Exposurc

time:37min~oEB

5 Exposure
6 Exposure~

time:l0min~

•
..

-<
c-=
c;Z

......... . .

-timc:37min
timc:37min. ..

.. . . ..

~
~

<

C!'
~

····· ···· . 1·········
...

;::>

0
10. 7

..............................!............................. .

.. .. .. . . . . . ..
2
10

3
10

TIME (min)Fig. 4. Reproducibility in background level at room
temperature during seven months .

.................................. \ ............................... .

10

2

TIME (min)Fig. 3. Influence of exposure time.

As shown in Fig. 4, we obtained overall
reproducibility of about ±35 %(± 25% by the
exception of NIB) in the background level, at theevacuation time of around 1,000 min, during sevenmonths. The symbols N8, N9 etc. in Fig. 4 show
the order of experiment after nitrogen venting.
Similar curves taken after baking (not shown inthis paper) also show reproducibility of about±2S%. From above, we can obtain following conclusions.
(1) Venting by 99.9998 % N2 gas is sufficient to. obtain the reproducibility. Wet air might
be used in some limited cases.
(2) Venting time is not so critical in case ofpure N2 gas venting.
(3) Exposure time is also not so critical.

(4) Our standard evacuation procedure, including some fluctuation because of the manual
operation, is sufficient to obtain the reproducibility.
(5) We did no degas operation for BA gauges.
Because outgassing from BA gauges is to becancelled out by the subtraction of the background at the actual outgassing measureInent (in case of the sample piece method).
This simple procedure seems to beadequate for obtaining the reproducibility.
Temperature of the sample chamber is also avery important factor for the reproducibility ofbackground. In our experience, outgassing ratechanges around 5per-cent by the change in thechamber temperature of 1°C.
Individual control of the chamber temperature
is not possible now but, if it is possible, control of
the chamber temperature within ±1 °C is desirable for the better reproducibil~ty of background.

-168-

RIKEN Accel. Prog . Rep. 26 (1992)

V -2-19. Outgassing Rate Measurement of Alumina Sample
T. Hanasaka, K. Watanabe, S.-YOkOllChi, Y. Niioka, and S. H. Be
We measured the outgassing rate of analumina(AI203) sample by means of a so-called
throughput method.
The measurement apparatus is shown
schematically in Fig. 1. The details will be
described elsewhere. 1 ) The surface area of asample chamber is 0.196 m 2. The conductance ofthe orifice between the sample chamber andpump side chamber was 2.15x10-3 m 3Is (for N2, at22°C). The background level and the reproducibility of the outgassing rate will be describedin Ref. 1).

separate each alumina plate. The surface area ofnuts is less than 1 % of that of the alumina plates.
Several characteristics of the sample are shownin Table 1.
_Table 1. Several characteristics of the alumina sample.

Fig. 1. Measurement apparatus.

The sample is made of 99 % alumina (type A479, KYOCERA INDUSTRIAL CERAMICSCORPORATION). Figure 2 shows the sanlple
block, and its surface area is 0.588 m 2. 68 pieces ofstainless steel M2 nut were used as the spacers to
ALUMlNA PLATESPACER (M2 NUT,
SUS304, 68 PIECES)(100 x 150 x 5mm,
2 PIECES)

Fig. 2. Laminated alumina sample.

Material

Alumina (dense type,A-479, KYOCERA)

Plate size
and numberof plate

1)114 x 139 x2 (mm)16 pieces2)100 x 150 x5
2 pieces

Surface area

5,883 (cm1

Surfacetreatment ofmaterial at
KYOCERAUltrasonic cleaningand drying(after sintering)

Density

3.8 (g/cm~

Alumina
contents

99 %The cleaning procedures of the sample at
RIKEN were as follows.
[1] Alumina plates.
(1) Supersonic cleaning in pure hot water.
(10 sec, at 60. . . 70 °C.)
(2) Drying in a dry furnace. (several hours, at
80°C.)[2] M2nuts.
(1) Degrease in 1.1.1 trichloroethane vapor.
(10 min, at 78°C.)(2) Rinse in 10 % hydrochloric acid . (2 . . . 3 sec, atroom temperature.)(3) Rinse in running water. (4 times, in 4 stage
flow bath.)(4) Rinse in pure water. (10 . . . 20 sec, at room
temperature .)(5) Rinse in pure hot water. 00 . . . 20 sec, at
60-70°C.)(6) Drying in a dry furnace. (several hours at
80°C.)
Note: Conductivity of pure water used was
below 0.2 J1S/ cm.

-169 -

The cleaned alumina plates and nuts were
installed in a clean glass beaker with a glass lid
and kept in a desiccator till the measurement
started.
The main procedures of the measurement wereas follows.
(1) The apparatus was vented by N2 gas.
(2) The flange for sample change was opened
for 37 min (without sample installation).
(3) The apparatus was evacua ted withou t the
sample at room temperature for obtaining
background data.
(4) The baking was carried out without the
sample, and background data after baking
were taken.
(5) The total outgassing rate from the sample
chamber at each time was calculated by
the following formula.

After one cycle, the sample was back to thedesiccator, and, after a few days, the next cycle
has started again with the same sample.
The outgassing rate vs. pumping time curves fortwo cycles are shown in Fig. 3. The origins ofpumping time are (1) the starting point ofevacuation for the "room temperatureevacuation" and (2) the starting point of cool
down for the "after baking". Obtained values areof the same order as the outgassing rates for clean
stainless steel or clean aluminum alloy.
(Room temperature evacuation)........................... ..." ........................°1'............. .
~o

Q=C(PI-P2),u'-'

Q: outgassing rate,
C: conductance between sample and pumpside chamber,
PI: pressure of sample chamber,
P2: pressure of pump side chalnber.
(6) The same procedures as in (1) and (2), but
the sample was installed at step (2).
(7) The same procedures as in (3), (4) and (5)with the sample.
(8) The same procedures as in (1 )~(5), but the
sample was taken out at step (2).
(9) Average value of two background measurements was subtracted from the measured
value with the sample.
(10) The outgassing rate per unit area of thesample was calculated.

- 170 -

10,11 &'-"--L...--l-~.L..L.J...I...L.-----I.---.l.....L...IL...L...L.L.U-_.L....-L...J
1
2
3
10
10
10

TIME (min)Fig. 3. Outgassing rate of alumina sample.

References
1) T. Hanasaka et al.: This Report, p .167.

RIKEN Accel. Prog. Rep. 26 (1992)

V -2-20. Outgassing Rate Measurement of BeCu Sample
T. Hanasaka, K. Watanabe, S. Yokouchi, Y. Niioka, and S. H. Be
Outgassing rate of a BeCu sanlple is measured'by means of a so-called throughput method.
The measuren1ent apparatus
is shown
schematically in Fig. 1. The details will be
described elsewhere) The surface area of asample chamber is 0.196 m 2 . The conductance ofthe orifice between the sample chamber andpump side chamber was 2.15x10-3 m 3 /s (for N2, at22°C). The background level and the reproducibility of the outgassing rate is described in Ref. 1). The sample plate is a JIS C1720P-1 /4H(BeCu25-1 /4H) copper-beryllium alloy (made by
NGK INSULATORS LTD). Figure 2 shows theshape of the sample, and its surface area is 2.02
m 2. Several characteristics of the sample areshown in Table 1.
Table 1. Several characteristics of the sample.

PUMP SIDE CHAMBER(DOWN ·SIDE CHAMBER)

Fig. 1.

Material(1)BeCu25-1/4H plate(JIS C1720P-1 /4H)
(2)BeCu25-H rod(JIS C1720B-H)

Plate size

0.2 x 200 x 100(mm)Number ofplate

50 sheets

Surface area

(1)Plate: 20,043cm 2(2)Rod :187cm 2
Total: 20,230cm2

Surfacetreatment ofmaterial at
NGK(1) Plate:Degreasein 1.1.1. trichloroethane and benzotriazole
treatment
for rust preventing(2) Rod:
Benzotriazole treatment
for rust preventing(after centerless grinding)

Chemicalcomponentof sample
plate

Be: 1.85(%)
Co+Ni: 0.27
Co+Ni+Pe : 0.30
Cu+Be+Co+Ni+Pe : 99.95

Measurement apparatus .

RING FORSUPPORTING
ROD(SUS304

SrnEW(BcCu25·H M2)

t; 5.6-2.5 x 15 )J/~

0.2 xlOO x

ZOO/SHEET)(BcCu25·H

Fig. 2. BeCu sample.

a:::>

The cleaning procedures of the sample at
RIKEN were as follows:(1)
Degrease in 1.1.1 trichloroethane vapor.
(10 min, at 78°C.)(2) Rinse in 10 % hydrochloric acid. (2,...3 sec,at room temperature.)(3) Rinse in running water. (4 times, in 4 stage
flow bath.)(4) Neutralization in 5 % sodium cyanide. (2,...
3 sec, at room temperature.)(5) Rinse in running water. (4 times, in 4 stage
flow bath.)(6) Rinse in pure water. (10,...20 sec, at room
temperature.)(7) Rinse in pure hot water. (10,...20 sec, at 60,...
70 °e.)(8) Rinse in acetone [special grade]. (1 min, atroom temperature.)- 171 -

(9) Drying in a dry furnace. (several hours, at
80°C.)
Note: Conductivity of pure water used
was below 0.2 JlS/cm.
The cleaned sample was installed in a clean
glass beaker with a glass lid and kept in a
desiccator till the measurement started.
The main procedures of the measurement wereas follows:(1) The apparatus was vented by N2 gas.
(2) The flange for sample change was opened
for 10 min (without sample installation).
(3) The apparatus was evacuated withoutsample at room temperature for obtaining
background data.
(4) The baking was carried ou t wi thou tsample, and background data after baking
were taken.
(5) The total outgassing rate from the sanlple
chamber at each time was caluculated by
the following formula.
Q=C(PI-P2)'
Q: outgassing rate,
C: conductance between sample and pumpside chamber,
PI: pressure of sample chamber,
P2: pressure of pump side chamber(6) The same procedures as in (1) and (2), but
the sample was installed at step (2).
(7) The same procedures as in (3), (4) and (5)with the sample.
(8) The same procedures as in (1)-(5),but the
sample was taken out at step (2).
(9) Average value of two background measurements was subtracted from the measured
value with the sample.
(10) The outgassing rate per unit area of thesample was calculated.
After one cycle, the sanlple was back to thedesiccator, and, after a few days, the next cycle
again started with the same sample.
The outgassing rate vs. pumping time for several

cycles are shown in Fig. 3. The origins of pumping
tiIne are (1) the starting point of evacuation for
the "room temperature evacuation" and (2) thestarting point of cool down for the "after baking".

(Room tempcrature evacuation)
10,5N.......................+.........- 0 - - DeCu(l)

-

!:.

••

BcCuU)--,j-k--- BcCu(3)--E 10,6

I I)

f"")

E

0

co 10,7

~

10

3

-~

c::.::

~

~

Eo-

E-

-<
c::.::

u

-<

10,8

10

C!'

2 c::.::

~

Q.,

:E

;Z;

1-4

~

~
~

Eo-

-< 10,9
C!'

10

1

E~

0

A

HcCu(4)llcCu(6)e(Aftcrbaking)

10,II L---L-L...L....J.....L....U..L1..---L--L.~...L.L.L.U-_"--'--' 0
3
1
2
10
10
10

TIME (min)Fig.3

Outgassing rate of BeCu sample.

Obtained values are of the same order as theoutgassing rates for a clean stainless steel or aclean aluminum alloy for the "room temperatureevacuation", and those for the "after baking" areextremely low. The reason for the extremely low
value may be due to the high diffusion constant ofa copper-rich alloy.
References
1) T. Hanasaka et al.: This Report, p .167.

-172-

RIKEN Accel. Prog. Rep. 26 (1992)

V -2-21. Support for a Normal Cell Vacuum Systemc.y. Xu, K. Watanabe, H.A . .Sakaue, M. Tsuchiya, and S.H. Be
The vacuum channel of a normal cell 30 m inlength consists of two bending magnet chambers(BMC), three straight section ones (SSC) with anabsorber, an insertion device dummy one (ID-C)
and two crotches. Each chamber is mounted on arigid holder and a sliding support and connected
wi th the bellows which allow the chamber tomove during installation and baking. The
chamber thermal expansion caused by baking at}50°C is shown in the following table.

magnet. The chamber weight is supported bythree stainless steel plates on the bending magnet
and the chamber is set up accurately with threeadjustors located at the middle and near bothends of the BMCl, respectively, as shown in Fig.3.
The middle adjustor is usually locked, but otherones can allow a slight chamber thermal
expansion in the beam and the horizontal
directions during the chamber baking.

Table 1. Thermal expansion caused by baking at 150°C
Length
(mm)
SSC1
SSC2
SSC3
BMC1
BMC2
IO-C
CrotchCrotch4621
5460.64356
3191.5
3073
4589
775
575

Thermal expansion (mm)Beam direction Horizontal
14.60
17.25
13.76
10.08
9.70
14.50
2.45
1.82

0.078
0.070

Fig.I. Schematic arrangement of the SSel.

The mouni-s for the SSC} of three different SSC'sand BMCI of two BMC's are described. The SSC}
is installed on the magnet girder using two mounts
near the station of the beam position monitor(BPM) as shown in Fig.1 after adjusting preciselya chamber position by a pair of special adjustors.
The rigid mount does not allow chamber motion at
the rigid point in any direction. The other mountis composed of a leaf spring and the support witha clamping screw as shown in Fig.2. The former is
to allow a slight chamber thermal expansion
along the electron beam direction during thechamber baking cycle, and the latter is forsupporting the chamber weight. These mounts can
suppress the chamber displacement at the stationof BPM's within the accuracy of 0.03 mm after
each baking cycle. The deflection of the leaf
spring due to thermal expansion makes thechamber downward, which interferes with thefunction of clamping screw. To solve this problem,
we bolt the leaf spring at the rib which is weldedon the chamber, so that the vertical thermal
expansion of the rib compensates this downward
deflection.
The BMCI is inserted in the gap of the bending-173-

Fig.2. Assembly of the sliding support.

S tOlnless sleet plate

Fig.3. Schematic arrangement of the BMI.

RIKEN Accel. Prog. Rep. 26 (1992)

V -2-22. Development of the LynxOS Device Drivers

T.Masuda, T.Nakamura, H.Takebe, and T.Wada

The control sub-system of the SPring-B storage
ring is designed to have a hierarchical structure
which consists of three layers such aspresentation, processing and equipment ones.
Recently such a structure is going to become astandard model of accelerator and large
experimental physics control systems in the world
as shown in Fig.I. In a processing layer, theSPring-B project team has decided to adopt a VME(Versa Module European)bus system withmicroprocessors as FEPs (Front End Processors).
These VMEbus systems which have a real time
OS (Operating System) are linked by a computer
network and distributed around the storage ring.
For an R&D study, we have introduced Motorola
Delta systems which contain a MVME147S 32-bit
single board computer based on MC6B030 and
LynxOS as a real time OS on a MVMEI47S. The
LynxOS is comparatively new and is one of the socalled "real time UNIX" operating systems. The
LynxOS complies with POSIX 1003.1(Application program Interface) and POSIX
1003.4 (Real Time Extension). PO SIX (Portable
Operating System Interface for Computer
Environment) is a standard OS proposed by theIEEE committee.
We intend to control a klystron test stand byusing this Delta system. Hence we need tooperate some I/O boards on a VMEbus. There are
two solutions to access and to control I/O boards.
One is the way with "shared memory" and thetlother is with a "device driver
We haveachieved an operation of I/O boards with sharedmemory in the first step, because theimplementation is easier. But the way with adevice driver is more advantageous because it cantreat hardware interruption and 1 msec timer
interruption, and it makes application program
hard ware independent. Hence as the second step,
we have developed the LynxOS device drivers
for VME boards used for a klystron test stand suchas DI (PENTLAND, MPV910), DO (Digital,
DVME DOUT2) and AI (PENTLAND, MPV906).
Device drivers are embeded in an OS kernel andis glued between a kernel and I/O devices. For
keeping hardware independency of the kernel,
UNIX device driver consists of a collection offunction routines called the "entry point" whichis called by the kernel in the same way asfunctions called by a main program written in C
language. We can access to the I/O devices only
from these entry points through the kernel.
LynxOS device driver has the same structure asthat of UNIX and has eight entry points per one
device driver. The name of entry points and their
purposes are shown in Table.l. Since the device
driver is embeded in the kernel, we usually needto modify a configuration table file and reboot
system to remake the kernel if we want to add a
new device driver. This process is called static
loading of the driver. But static loading is very
troublesome especially at the development time•

Backbone Network
Presentation Layer

Process Layer

Equipment Layer
Devices

Devices

Devices

Devices

Fig.I. The standard model for accelerator and large experimental physics control systems.

-174-

Table 1. LynxOS device driver entry points and its
purpose.

Entry Point
open
close
read
write
selectioctl
installuninstall

Purposecalled when device is opened
called when device is closed
called to read data
called to wri te da ta
support select system calldevice control
called to install major device
called to remove major deviceof the device driver. LynxOS offers powerful anduseful functions for development of device drivers
which are called dynamic loading. We canlink/unlink the device drivers to the kernel withsome shell commands. All things we need to do
are merely to declare the entry points in a form of
the specific stru'c ture at the end of the device
driver. We need not to modify a configuration fileand to reboot the system.
There are no
performance penalty by using dynamicallyloaded device drivers.
If we finish thedevelopment and test of LynxOS device driverwith dynamic loading, then we can load it
statically according to the LynxOS static loading
procedure.
Since device drivers are embeded in the kernel ,we c~nnot use system calls or standard C libraryfunctIons, but some special functions with a Cinterface are provided only for device drivers.
These functions naturally depend on the OS
which are called "driver service calls" on
LynxOS. The LynxOS supports many driver
service calls such as dynamic memory allocation,
timer interruption (10 msec and 1 msec), hardwareinterruption dispatch, software interruption,
thread, semaphore, signal, DMA chain and so on.
Hence we can describe the LynxOS device driveralmost in C language with these device service
calls.
We have implemented hardware interruption
from the I/O boards on VMEbus with LynxOS
device driver. All things we have to do in thedevice driver are to describe an interrupt software
handler and to establish a relation between theheader address of interrupt software handler andinterrupt vector number which is sent to CPU fromthe I/O device which demands for aninterruption. The latter is implemented with a

specific driver service call which has interrupt
vector number and address of an interrupt
software handler as arguments in installing entry
point. It is very easy to implement hardwareinterruption with this service call.
We have composed the LynxOS device driver
for a MPV906 AI board. Generally speaking, anAI board has more powerful and complicatedfunctions than a OJ /00 board, hence it is moredifficult to _make a device driver for an AI board.
The MPV906 is a 12-bit analog-to-digitalconverter board with 64 singleended/32
differential input channels, and the board
operation can be selected from two operating
modes (continuous/ transient), two dataacquisition modes (polling/interrupt mode), four
trigger sources (internal/ software / event! external
trigger), 64/32 data acquisition channels, threegain settings (xl / xl O/x 100), conversion period (forinternal trigger), seven interrupt levels andinterrupt status/ID (interrupt vector number) by
the software program. It has 64 words memory forconverted data. Since we can set the board
operation from an application program through adevice driver, the device driver must be written
to support these available functions. It is notnecessary to implement all functions to drive the
klystron test bench. Hence we have fixed theda ta taking way as taking 64 samples per one
read cycle for a specific input channel with atransient operation mode. It takes about 16.5 msec
per one read cycle by polling mode with aninternal trigger (30 J,lsec per one conversion), andabout 17 msec by interrupt mode with an internal
trigger (30 J,lsec). One read cycle time includes one
to open the device, set the device, read data andclose the device.
We intend to establish the ways of exclusive
and synchronous control of processes with device
access and communication between theseprocesses. We must implement these ways at bothdevice driver level and upper application
program level. After these ways are established,
we intend to control VMEbus systems from apresentation layer which consists of EWS(Engineering Work Station) through network.

References
1) T. Wada: RIKEN Accel.Prog. Rep., 24, 202 (1990).
2) T. Masuda, T. Nakamura, T. Wadal and Z. Wang:
RIKEN Accel. Prog. Rep., 25, 240 (1991).
3) R. Rausch, Ch. Serre: "Common Control System for
the CERN accelerators", International Conferenceon Accelerator and Large Experimental Physics
Control Systems, Tsukuba, Japan (1991).

-175-

RIKEN Accel. Prog. Rep. 26 (1992)

V -2-23. Test of VME Remote I/O System Slave Card Type-A
H. Takebe, M. Hasegawa, *and K. Matsuo*
Power supplies for the SPring-8 Storage Ring
magnets[1] are controlled by a VME[2] remote I/O
card (RIO) system[3]. RIO cards of type-A and -B
were made and tested in this year. This RIO
system was initially developed for the HIMACHEBT system at the NIRS (National Institute of-Radiation Science) with a Multi-Bus system, andmodified for the VME bus system at this time, by
Mitsubishi Electric Corporation.
Figure 1 shows a block diagram of the RIO slavecard type-A.
The RIO card type-A has a 16 bits
ADC (AD7701), a 16 bits DAC(AD669), 8 bits

DeviceRemote I/O Card...--------------------------------!y£~:~---------------------------------..,.
\\: [oro]

~

:\

:\

E/O

:
:
:

(Power Supply:
St-PS):::I
II
R~-4s5.

~\

II

II

i ±lOV:II

RHerence

:

I I

HD~

\

:

,

:

!1

:
:\

Metal Wire\\

AD7701:\: 0-1 V or
\ ±lOV

:

Shunt

:

!: Command
I Status Inout

1:~

8 bit::::>\.

\. ,,"""-------------------------------------------------------------------~
Fig.I. Block diagram of the RIO slave card type-A.

digital outputs and 8 bits digital inputs. This card
is a single height of a Euro-card size as shown in
Fig.2. Type-B has a 32 bits digital output andinput with a double height of Euro-card size.
The digital I/O's are all photo isolated, and canbe connected to relay circuits, photo-coupler, andTTL level circuits.
The test bench system consists of a VME chassis
and RIO cards. They are linked by an opticalfiber cable. This VME system consists of 'a VME
CPU module (MVME147), an Ethernet module, an
RIO master module (Fig. 3), and an active starcoupler. An operation test and a DAC accuracy
check were done by using VME Lynx-OS[4] and C
language test program. The following tests of the
ADC and DAC of the RIO type-A were achieved:
1) Accuracy and linearity of the DAC,
2) DAC out drift check during 500 hours,
3) Accuracy and linearity of the ADC,
4) ADC out drift check for 500 hours.

Fig. 2. Prototype RIO-A slave card.

... Mitsubishi Electronic Co.

-176-

These tests were done by using a DVM (HP :3458A) at room temperature (25 - 28°C). The DAC
output is connected to the ADC and DVM.

Differences between the DVM readings and thevalues calculated from the ADC data are lessthan ±1.2 mV (±1.2 x 10-4 to the full scale value).
These can be also reducedto ±5 x 10-5 by adjusting
the scaling YR. Reproducibility of the reading of
the AOC is better than ±8 x 10 -5 in 2 days.
A cyclic time of the RIO serial data transfer
was measured to be 0.19 ms for a 1 slave card. An
RIO control program development in the VME
Lynx-OS and design of RIO network is now inprogress. A test of connection between the RIO
type-B and a main power supply is scheduled in
1993.
>
C

1'"4

i>

0.02

'?

0.00

fI:l

-0.01

~

-..- R(%)

0.01

U

<
Q

-0.02

~

-0.03

I¥

o

20000 DAC

s:f oOO

60000

80000

Fig. 4. Difference in -perGent between the measured .
DAC output voltage (DVM) and an ideal DAC
voltage along the DAC set value. The linearity
error will be reduced to within ± 3 x 10-5 when thescaling VR is adjusted.
0.0005 - - - - - - - - - - - - - - - - .

DACSet = FfFF( 10 V)

Fig.3. Prototype RIO master card.

•~ o.oooo ...
·-------------_--tI·
'"Q
•
-

:::

Figure 4 shows a difference in percent between
the measured DAC output data obtained by the
DVM and the ideal DAC voltage along the DAC
set value. The DAC was set in 1024 step from 0 to
65535(FFFF). It was changed in upper 4 bits only.
This measurement was also done by changing all
the bits of DAC set value which were turned onalternatively. The errors were within 0.012%
and -0.025%. These can be reduced by adjusting
the VR of the card, and the linearity error will
become within ±3 x 10 -5.
Figure 5 shows a long time drift of the DAC
output when the data is FFFF and 10.03 V over
500 hours. The maximum drift is less than ±0.0003
V (±3 x 10 -5 against the full scale ).

-0.0005

o

•

I

100

.

I

200

Hours

400

300

-

.

500

600

Drift (V)Fig. 5. Drift of the DAC output data, checked by
the DVM when the DAC set value is FFFF in
hexadecimal for 500 hours.

References
1) H.Takebe, N.Kumagai, J.Ohnishi, S.Matsui, K.
Kumagai, and S.Motonaga : This report, p. 157.
2) Versa Module for European.
3) H.Takebe et. al. : RIKEN Accel. Prog. ,Rep. 25, 209,
(1991).
4) Real -Time Systems. Inc.

-177-

RIKEN Accel. Prog. Rep. 26 (1992)

V -2-24. Design of RF Low Power System for the

SPring-8 Storage Ring
Y. Ohashi, H. Ego, M. Hara, K. Inoue, Y. Kawashima, H. Suzuki, * I. Takeshita,and H. Yonehara*
A low power control system design of the SPring-8
storage ring has basically completed. The systemdescribed in this report includes 508.58 MHz reference
signal transmission, klystron out phase and amplitude,
and cavity tuning controls.
An ultra-stable reference signal generator, which will
be installed in the RF "A" station (or central controlroom), will supply the main RF frequency of508.58MHz: The signal is distributed in succession to
the nearby stations and the synchrotron as shown in
Fig.l. A special single-mode fiber-optic cable, 1) which
compensates temperature drifts, is used for the signaltransmission. Phase accuracy for transmitting signal
over a 500m fiber-optic cable is about ±1· without aphase-lock loop(PLL) under the ambient temperature
range between 20 and 30·C (about ±5· between 20 and
40·C).2) Individual two fiber-optic cables are to be used
to compensate phase drifts within 1· by the PLL and

As in Fig.2 RF signals picked-up from 8 cavities aresent to a vector sum over phase stable coaxial cables.
The vector-summed signal is split into two. One islinearly detected and used for the amplitude control of
the klystron. Since the cavity voltage is used for the
klystron output power control, a beam loading effect isspontaneously compensated. The other sum-signal is fed
into a phase detector to lock the klystron out RF signal
phase.

Fig.2. Schematic diagram of RF control system.

SUngC lRing

Fig.I. Fiber-optic link for the 508.58MHz reference signal
tmsmission.

to watch actual drifts or any troubles in the referenceline by monitoring phase control voltages as well. 3) A
single fiber-optic cable might be used with opticaldirectional couplers if a difference in the characteristics
in both cables is a problem. A first timing signaltransmission will be done with the same fiber-optic
system.

* Japan Atomic Energy Research Institute,

A picked up signal phase from each cavity is comparedwith the input phase. A phase drift, which is caused by
the thermal detuning or reactive beam loading effectappeared in each cavity, is compensated by driving a
stepping motor of the tuner.
A part of the system has been examined during a highpower test. RF components needed to test and improve
the overall system are being purchased, and a study of
the whole system will be extensively carried out in a
half year. The low power system described here is to bebasically adopted in the booster synchrotron.

References
1) 1. Urakawa: Particle Accelerators, 29, 251 (1990).
2) Y. Kawashima, H. Ego, M. Hara, K. Inoue, Y. Ohashi,
H.Suzuki, I.Takeshita,and H.Yonehara: "On the temperature dependence of an optical fiber and related modules forthe timing system of the SPring-8" in this report, p.179.

3) E.Ezura, K.Akai, H.Hayano, M.Ono, M.Suetake,andT. Takashima: "The low level RF system for
TRISTAN main ring" in Proc. 1987 Particle
Accelerator Conf. (Washington, D.C., USA, 1987)-178 -

RIKEN Accel. Prog. Rep. 26 (1992)

V -2-25. On the Temperature Dependence of an Optical Fiber andRelated Modules for the Timing Systemof the SPring-8
Y.I{avvashima, B.Ego, M.Hara, IClnoue, Y1>hashi, H.Suzuki, *I. Takeshita, and H.Yonehara*
We have developed a transport systemof the timing signal for the SPring-8. The
method and relevant instruments are briefly
described.
The fundamental radio frequency ( RF )of 508.58 MHz is transmitted to the four
RF power stations distributed in a storage
ring with a circumference of 1436 m andan injector system. An RF, for example, istransmi tted from a station to the other one.
Received RF is divided into two, then oneof them is returned to the original station,
where the two RF signals, transmitted andreceived, are compared, and a phase difference between them is obtained. The phasedifference of the RF between power stations
must be kept within 1°, which corresponds
to about 5 psec. The longest distance froma station to the neighboring one is about
400 m and the phase between them must
be stable. Its stability must be kept in allseasons.
To realize our 'purpose, we adopted optical fibers to transmit RF signal. We also usethem as a timing signal transmitter for the
beam kicker. An optical fiber is much more
useful compared with a co-axial wire cable
in point of some problems such as attenuation in a long distance transmission andan electro-magnetic noise. In these days,
we easily get an optical fiber whose phasestabilization is guaranteed in a room temperature around 20°C. The only issue totreat the optical fiber was modules such as
an electrical to optical (E/O) and an optical to electrical (OlE) fiberoptic transmitter and a receiver with good response up to
several tens GHz-high radio frequency, but• Japan Atomic Energy Research Institutethey have also been developed and we canget them as commercialized products.

20

!f

u

::

Q.

"

~

10

...

f

tI

~
Q

0

Temp.ralura ( ·c )Fig.l. Temperature dependencesof E/O and OlE obtained by adigital oscilloscope.
We have measured the temperature dependence concerning a time jitter of an
EIO, an OlE and an optical fiber. Firstof all, the EIO and OlE connected with a
I-m long optical fiber was placed in a constant temperature box. We measured their
specifications in a temperature range from
23.3°C to 42.6°C. The obtained results areshown in Fig.l, where the fluctuation of thedelay time in a wide range of temperature
is as small as the phase tolerance of the RF.
The room temperature of a storage ring is
to be kept at 27±I°C, so that we may expect the stabilities of the EIO and OlE. As
to a 500-m long optical fiber, we have done
the same experiment and obtained the same
result as shown in Fig.2.
Consequently, we can expect the stability of a timing system comprising RF signal transmitter, receiver and optical fiber
wi th enough reliability, as long as the room-179-

temperature in the storage ring and thebooster synchrotron would be kept around
27°C within a few degrees as a temperaturedrift.
20

t-508.58 MH%
500 m lone

15

.::
--.
.;
...

10

41

~

0

::2

::

"

.c:

0

II.

-5

-10

-20

o

20

Tempualure ( ·c )40

eoFig.2. Temperature dependence ofa phase stabilized optical fiber
detected by a vector voltmeter.
In an actual system, in order to cancel
a phase difference between stations, a phaselock system which consists of hardware is tobe equipped, and the phase stability would

be completed perfectly.
We are going to use the same E/O, OlE
and optical fiber to kick a beam from a linac
to a boqster synchrotron and also from thesynchrotron to the storage ring. In this system, a pulse signal is transmitted. We haveto, therefore, use a pulse shaper circuit (PS)after the OlE module because of attenuation. Taking into account the small change
of a pulse height due to a little temperature dependence of a transmission system,a constant-fraction-discriminator ( CFD )module was inserted after the 0 IE. In caseof a constant pulse height, total time jitter including E/O, OlE connected with a
500-m long optical fiber and a CFD was obtained to be 13 psec as a sigma value. Even
if the pulse height is varied from -100 InV
to -200 m V, the transit time of the CFD ischanged by only 20 psec.
In the SPring-8, new devices such as an
optical fiber and the related n10dules are
employed, and the reliability of RF transmission and timing system must be remarkably improved.

-180-

VI. RADIATION MONITORINGRIKEN Accel. Prog. Rep. 26 (1992)

VI-I. Radiation Monitoring of RILAC, TANDETRON,
and Hot Laboratory
I. Sakamoto, M. Yanokura, T. Kobayashi, M. Iwamoto,I. Kohno, and T. Inamura
Radiation monitoring was carried out for
RILAC, TANDETRON, and the hot laboratory inthe cyclotron building from October 1991 toSeptember 1992.
(1) Radiation monitoring of RILAC
The leakage radiation was measured atvarious points outside the RILAC building in
July.
When RILAC was used for the RRC
injector with 40Ar S + beam of 1B.7-MeV, noleakage of,,( rays and neutrons from the RILAC
building was detected. No contamination due
to residual activities was foLind on the floorsof the controlled area in the RILAC building inthis period.
(2) Radiation monitoring of TANDETRON
X-ray monitoring was carried out for
TANDETRON, when a copper target was
bombarded with 1.6-MeV H+ ions of 500 nA.
The maximum dose (1 cm dose-equivalent)
rate measured around TANDETRON was 1

J.1.Sv/h. No leakage of X-rays was detected notorily outside the TANDETRON room but also
around the target chamber.
(3) Air and surface contaminationin the hot laboratory
Radioactive substances were handled in the
hot laboratory. The radioactivity in air at theexit of draft chambers was measured every
month, and the radioactivity was found small(the order of 10- B Bq/cm 3 ).
The surface
contamination on the floors was below 10- 2
Bq/cm 2 .
(4) Contamination of drainage
Each time the drainage from the hotlaboratory was drained outside the cyclotronbuilding, the radioactivities in the drainwater were measured.
The radioactivities
were found to be of the order of 10- 4
The total activity in aqueous
Bq/cm 3 .
effluents was 12 kBq.

-181-

RIKEN Accel. Prog. Rep. 26 (1992)

VI-2. Exposure Dose Monitoring for Radiation Workers at
RIKEN Accelerator Research Facilities
M. Miyagawa, I. Sakamoto, T. Katou, Y. Matsuzawa,S. Kagaya, H. Katou, and T. Inamura

The external exposure dose of radiation
workers at RIKEN Accelerator Research
Facilities was mearsured by using y-ray andneutron film badges. Four hundred and twentyeight radiation workers were registered in fiscal
1991 (April 1991-March 1992), and theirexternal doses recorded are given in Table 1.

One nuclear chemist was exposed to y-rays at
an external dose of 0.1 mSv. (This is about
one-tenth of the natural external dose/year inJapan.) The external doses owing to thermal
and fast neutron exposures were below thedetection limit.

Table 1. External exposure doses (effective dose-equivalent in mSv) recorded for radiation
workers at RIKEN Accelerator Research Facilities in fiscal 1991(April 1991-March 1992).
Number of personel
Field

Dose

0.1-1

>1

undetectable

(mSv)

(mSv)

Total

Collective
dose
(mSv)

Accelerator physicists
and Operators#
Nuclear physicists
Researchers in other fields
TANDETRON workers
Health physicists

83

0

0

83

0

198
118
20

0
0
0
0

198
119
20

8

0
1
0
0

8

0
0.1
0
0

Total

427

1

0

428

O. 1

#: Operators of the RIKEN Ring Cyclotron, RIKEN AVF Cyclotron and RILAC.
The average dose per person was 0.0002mSv; the maximum individual dose was O.lmSv.

-182-

RIKEN Accel. Prog . Rep. 26 (1992)

VI-3. Measurement of Neutron Flux with the Activation Method
S. Nakajima, N. Nakanishi, S. Fujita, H. Matsumoto,K. Tanaka, and T .. Shikata*
A series of experiments to measure the secondary
neutrons produced by a reaction of the 135MeV/nucleon
14N ions with a thick iron target has been made toobtain information for shielding caluculations. The
neutron energy spectra and their angular dependence were
measured last year using the activation analysis
technique 1). It is difficult to get accurate spectrum by
this method, but its approximate shape was obtained .
We found that the method is simple and inexpensive
but is useful to detennine the approximate shape of thea).,---_... _................... ;; ..................... ~ ..............._......._-_......... _......._--_ ...... .

;!

z
:r.
<
x
o

0":'

4096

i048

CHANNEL NUMBER

b)
Loe
...J

. - . -..-

•• -

.-

.- - -- . • - .. . . . . . - ... .... .... .. . - . . .. .... .

101

Z
Z
~

-i

e_

... ' _... -• • - . .. . . ..... --- - - -

i ' -_...... _....._._- -----... .... . -.-. .... .-.

~. ~~E~u,r ·~·•••'_": -.... ; :.:.~.:~.======_. _.:

::J

g

.

o.

.. .... . ..

-~~:==:~

'09~

104.

CHANNEL

spectrum. Systematical dependence on the target
elements, the incident particles and enegies may beeasily obtained with this technique.
This report is concerned with a similiar measurementfor 135MeV/nucleon deuterons incident on a thick irontarget (about 7cm long) in which the primary beam wascompletely stopped. The same elements as in theprevious case(a carbon block and the seven metal foilsof AI, Fe, Co, Ni, Ag, In, Au) were used for theactivation samples, and placed at the angles of 0, 30,
60, 90, and 120 degree with respect to the incident
beam.
The carbon block was irradiated forapproximately 2 hours and the seven metal foils were
irradiated for about 16 hours by the secondary neuttons .
The measurements of y-rays from the activatedelements were perfonned after the irradiation . As an
example, a y-ray spectrum from the activated 59Co foil
is shown in Fig. 1 together with that taken in the caseof 135 MeV/nucleon 14N + iron reaction. The y-rays
whose energies correspond to those from the reaction
products of (n,2n), (n,3n), (n,4n), (n,5n) were observedin both the spectra. The reaction Q-value is about
30MeV for the (n,4n) reaction and about 40MeV for the(n,5n) reaction. Significant presence of neutrons withenergies of larger than 40 MeV is indicated.
The relative intensities among the peaks (n,2n),(n,4n), and (n,5n) were some-what different in twocases. A prominent peak was the (n,4n) for the 14N's
case and the (n,2n) for the deuteron's case. This isprobably because much heigher energy neutrons were
produced in the 14N induced reaction. Any otherremarkable difference was not readily seen in the two
spectra. Detailed analysis is in progress.

NUMBER

Fig. 1. "(-ray spectra from activated 59Co foils taken in
the cases of a) 14N + iron reaction. b) deuteron +iron reaction.

References
1) T. Shikata et al.:RIKEN Accel. Prog. Rep., 25,171(1991)* Diseased-183-

RIKEN Accel. Prog. Rep. 26 (1992)

VI-4. Leakage Radiation Measurements in the Ring Cyclotron Facility
S NakaJlma,..
N. Nakanl'shl', S.Okamoto,* H. Matsumoto, T. Takagi,**
S. F UJI"ta,.
K. Ikegami, and T. Inamura
The radiation safety control system has worked
steadily this year, performing radiation monitoring
continuously and automatically. We, however,encountered the following problem.
When experiments in an experimental vault E6 are
carried out in the course of RIPS, a primary beam isseparated from secondary beams with a magnet D 1 in a
distribution corridor (See Fig.1 (a) ), and stopped in it.
In some cases of experiments in the E6 vault, a gas
activity detector Nal ( 2" x 2" Nal ) was activated inspite of a very low radiation level in the vault. The gas
activity detector is on the 2nd basement floor at a
distance of 6.6 m from the magnet D 1, and 1.8 m thickconcrete exists between them.
To solve this problem, we measured leakage
radiations around the gas activity detector using a

primary beam of 135 MeV/u 12C6+ particles. At that'time, leakage neutrons from the AVF cyclotron, Ring
cyclotron, E6 experimental vault, and the distribution
corridor were monitored using a neutron dose meter atvarious points in the facility(See Figs.l a,b). Results
are summarized in Table 1.
Table 1. Dose rates of neutron leakage radiation from themagnet Dl in the beam distribution corridor. (SeeFigs.1-a.b).
Measurod

Pol n t
I )

2)
3 )

-1 )
5)
6)

~

7 )
8 )
( 9)
( I 0)(1 I )( I 2)( 1 :J)E6( I 4)( I (;)( I 6)( I 7)( I 8)( I 9 )
( 2 0)( 2 I )
( 2 2)( 2 3 )
( 2 -1 )

(a)

(2 5)
( 2 6 )
( 2 7)(2 8)(2 9 )Dose
Rate(ItSv/h)/(PIt A)

2 5. 1505. 2
O. 6 I 0
0.0414
1. 09
O. 3 9 1
0.0617
O. 02
3. 3 52.

I 2

7. 4 3
1. 7 6
O.

325

O. 306
1. 7 7
1 2. fj
fj.

O.
O.

-1 2
0-1
1 3 0

O. 1 63
9. 04
2 9 2.
O.
O.
I.
1.
2.
1 5.
5 2.

1
0 6 22
1 1 3

9 4
8 9
1 8
5
2

:!So
:!oo

lso

~

So

·R

....

(b)

Fig. 1. Layout of RUffiN Ring Cyclotron facility as of1992. a) Plan view of the 1st basement floor; b) Planview of the 2nd basement floor. Points, where leakage
radiations were measured, are denoted by the numbers in
the parentheses.

~

100

-.g

Fig.2. The contour lines of neutron dose rates Ip~A on the
2nd basement floor.
The position of activity detector
is (-3.1) in the X-Y coodinates.

* Institute of Physics, University of Tukuba.
** Fukudagiken.
-184-

Leakage neutrons from the RIPS primary target pointin the distribution corridor were also measured withneutron dose meters at 60 points in steps of 1 m on the
2nd basement floor. The contour lines of radiationlevels are shown in Fig.2, where X and Y lines stand forparallel and perpendicular ones with the beam line in the
distribution corridor. The origin of the coordinate istaken at the position on the 2nd basement floor justright under the magnet D 1. The highest dose rate was
detected at the position of the gas activity detector, thatis, the X line (-3 m) and the Y line (1 m). It seems thatthe gas activity detector was activated by high energy
neutrons from the magnet D 1.
We also measured "( rays with a Ge detector aroundthe gas activity detector. We shielded the Ge detector
with lead of 5 crn thick because the gas activity detector
is enclosed with lead of 5 cm thick. Figure 3 shows theenergy spectrum; high energy components up to about
10 MeV are observed, which may be coming from highenergy neutron-induced secondary "( rays.

From those results it is concluded that we have tochange the position of the gas activity detector and toshield locally the target chamber. It is very muchdesirable to develop monitors which are suitable forhigh energy "( rays and neutrons.
LOG

4( MeV)
Fig. 3. An energy spectrum of ,,(rays by a Ge detector at theactivity detector.

-185-

RIKEN Accel. Prog. Rep. 26 (1992)

VI-5. Residual Activities in the Ring Cyclotron Facility
S. Fujita, S. Okamoto, *H. Matsumoto, K. Tanaka, N. Nakanishi,
and T.Inamura
Residual activities were measured at various points in
the Ring Cyclotron Facility after almost every beamtime and during the overhaul throughout the year. In thefollowing we describe significant residual activities

Fig. 3. Layout of the RUffiN Ring Cycrotron facility as of1992. Monitoring positions are denoted by X . Detection
points of residual activities on the beam lines are denotedby alphabets.

Fig. 1. Detection points around the RIKEN Ring Cyclotron:
an electrostatic deflection channel, EDC; a magnetic
deflection channel I, MOC 1; a magnetic deflection
channel 2, MDC2; a main differential probe I, MOPl; amain differential probe 2, MDP2; a main differential
probe 3, MOP3. Indicated numerals are dose rates in unitsof IlSv/h.

Table 1. Summary of the residual activities measured along
the beam lines with an ionization chamber survey meter.
Alphabets indicate the detection points in Fig. 3.
Detection
point

a
b
c
d

e
f
g

h
i
j

Beam

DOSE UNIT : ~Sv/hFig. 2. Dose rates detected inside the injector AVF
cyclotron. They are given in units of IlSv/h.

-186-

Date

50
30

Nov. 5,1991
Mar.l0,1992
Mar.l0,1992
Mar. 10,1992
Mar.l0,1992
Mar.l0,1992
Oct.12,1992
Oct.12,1992
Oct.12,1992
Oct.12,1992
feb. 5,1992
Aug. 6, 1992
Aug. 6, 1992
Feb. 5, 1992
Aug. 6, 1992
Oct. 9,1992
May.28,1992
Oct. 7,1992
Jul. 3,1992
May. 1,1992

45
20
28
80
1150
730
160
170

40
40

k
1
m

50

n

5000

o

60

p

46

q

100
300
28
27

r
s
t

* Institute of Physics, Uiversity of Tukuba.

Detecteddose rate( tLS v / h)observed.
From July 29 to August 1, the last experiment in thespring term was carried out with an 40Ar16+ beam of 90
MeVlu in the experimental vault E6.
A routine overhaul was made in August, and the dose
rates due to residual activities of the Ring Cyclotron andthe injector AVF cyclotron were measured on Aug. 4
and 24, respectively. Those results are shown in Figs.
1 and 2 together with detection points. The residual
activities at the deflectors of the Ring Cyclotron andinjector AVF cyclotron were slightly increased thanthose of a previous report. 1)
In the period from Oct. 16, 1991 to Oct. 15, 1992,:

residual activites were measured along the beam lines
with a portable ionization chamber. The detection points
above 20 J,1Sv/h are shown in Fig.3. Table 1
summarizes the detected dose rates with measured dates.
The maximum dose rate was 5000 J.1Sv/h at the point n(the production target chamber of RIPS) in the beam
distribution corridor.
References
1) S. Fujit~ S. Okamoto, N. Nakanishi, I. Sakamoto. and
T. Inamura: RIKEN Accel. Prog. Rep.,22,246(1991).

-187-

VII. LIST OF PUBLICATIONSVII. LIST OF PUBLICATIONS
H. Tanaka, T. Nomura, H. Orihara,
S. Kato, M. Ohura, T. Kubo, N.
Inabe, A. Yoshida, T. Ichihara, M.
Ishihara, I. Tanihata, H. Okuno, T.
Nakamura, S. Shimoura, H. Toyokawa, C.C. Yun, H. Ohnuma, K.
Asahi, A. Chakrabarti, T. Mukhopadhyay, and T. Kajino: "Decay Propertyof 2°N a for the Onset Mechanism of the
Rapid - Proton Process", ibid., 46, 361(1992) .
11) K. Yoshida, J. Kasagi, H. Hama, M.
Sakurai, M. Kodama, K. Furutaka,K. Ieki, W. Galster, T. Kubo, M.
Ishihara, and A. Galonsky: "Neutron
Emission for the Fusion of 4°Ar+ Ni,
92Mo, 122Sn Reactions at EI A = 26MeV" ,ibid., p. 96l.
12) H. Kusakari, M.Oshima, A. Uchikura, M. Sugawara, A. Tomotani, S.
Ichikawa, H. Iimura, T. Morikawa,T. Inamura, and M. Matsuzaki: "Electromagnetic Transition Probabilities in
the Natural- Parity Rotational Bands of155, 157Gd", ibid., p .1257.
13) S. Kim and S. Ohta: "QCD Thermodynamics with Eight Staggered
Quark Flavors on a 163 X 6 Lattice",
Phys. Rev. D, 46, 3607 (1992).

1. Accelerator development and accelerator
physics

1) J. Ohnishi, H. Takebe, K. Kumagai,
and S. Motonaga: "Field Measurementsof Prototype Magnets for the SPring-8
Storage Ring", IEEE Magnetics, 28,
546 (1992).
2) C. Ka to, A. Yoneda , T. Imai , K.
Munakata, and T. Kohno: "Test of
Two-Dimensional Position Sensitive
Silicon Detector for Cosmic Ray Telescope by a Light Pulser" , Jpn. J. Appl.
Phys., 30, 3549 (1991) .
3) T. Nakagawa, T. Kageyama, M.
Kase, A. Goto, and Y. Yano: "Mechanism of the Increase of Highly Charged
Ion Intensity by Use of an Electrode in
the First -Stage Chamber of the RIKEN
10 GHz Electron Cyclotron ResonanceIon Source", ibid., 31L, 1129 (1992).
4) Ch. Ellert, D. Habs, E. Jaeschke, T.
Kambara, M. Music, D. Schwalm, P.
Sigray, and A. Wolf: "An Induction
Accelerator for the Heidelberg Test
Storage Ring TSR", Nucl. Instrum .
Methods Phys. Res., A314, 399 (1992).
5) K. Watanabe, Y. Oikawa, H.A. Sakaue, S. Takahashi, C. Y . Xu, T.
Hanasaka, Y. Hirano, S. H . Be, S.
Yokouchi, T. Nishidono, and R. S. In:"Vacuum System for SPring-8 Storage
Ring", Proc. 8th Meet. on Ultra High
Vacuum Techniques for Accelerators
and Storage Rings KEK (Nat!. Lab. forHigh Energy Phys.), p. 21 (1992).
6) H .A. Sakaue, Y. Oikawa, S. Takahashi, C.Y. Xu, T. Hanasaka, Y.
Hirano, S.H. Be, S. Yokouchi, and K.
Watanabe: "Pumping System for SPring8 Storage Ring", ibid., p. 88.
7) S. Yokouchi, Y. Hirano, K.
Watanabe, S.R. In, and S.H. Be:"Pumping Speed of a Distributed NEG
Strip", ibid., p .129.
8) S. Hirenzaki, H. Toki, and T. Yamazaki: "(d, 3He) Reactions for the Formation of Deeply Bound Pionic Atoms" ,Phys. Rev. C, 44, 2472 (1991).
9) M. Kat6, W. Bentz, and K. Tanaka:"Neutral Pion Condensation in Quark
Matter including Vacuum Fluctuation
Effects", ibid., 45, 2445 (1992).
10) S. Kubono, N. Ikeda, Y. Funatsu, M.

2. Nuclear physics and nuclear instrumentation-189-

1) S. Kubono, N. Ikeda, M.H. Tanaka,
T. Nomura, I. Katayama, Y. Fuchi,
H. Kawashima, C.C. Yun, Y. Tajima,
M. Yosoi, H. Ohnuma, M. Ohura, T.
Kubo, I. Tanihata, H. Toyokawa, H.
Orihara, H. Miyatake, T. Shimoda, R.
N. Boyd, and T. Kajino: "Study of the
Key Reaction 8Li(a ,n) HB for the Primordial N ucleosynthesis", Proc. Int.
Workshop on Unstable Nuclei in Astrophysics, eds. S. Kubono and T. Kajino , World Scientific, Singapore, p .131
(1991) .
2) K. Yuasa-Nakagawa, Y.H. Pu, S.C.
Jeong, H. Fuziwara, T. Mizota, S.M.
Lee, T. Nakagawa, B. Heusch, K.
Ieki, T. Sugimitu, and T. Matsuse:"Complex Fragment Mass Distributionsin 84Kr+ 27 AI at E I6b =10.6MeV lu",
Towards a Unified Picture of Nuclear
Dynamics AlP Conf. Proc., No. 250,
p .100 (1992).

3) T. Matsuse, S.M. Lee, Y.H. Pu, K.
Yuasa-Nakagawa, C. Beck, T. Nakagawa: "Statistical Emission of Complex
Fragments from Highly Excited Compound Nucleus", ibid., p .112 .
4) K. Yazaki: "Quark - Meson Hybrid
Model for Nuclear Force and Nuclear
Currents", Few-Body Systems, Supp!.,5, 441 (1992).
5) M. Koizumi, M. Azuma, T. Horiguchi, T. Inamura, T. Ishizuka, A.
Iivonen, H. Katsuragawa, S. Matsuki,
K. Morita, T. Murayama, I. Nakamura, M. N akaoka, K. Shimomura,T. Shinozuka, I. Sugai, Y. Tagishi,
M. Takami, K. Valli, M. Wakasugi,
and A. Yoshida: "Collinear Fast AtomicBeam Laser Spectroscopy at RIKENGARIS/IGISOL" , Hyperfine Interact.,74, 181 (1992).
6) S. Matsuki, K. Shimomura, 1. Ogawa,K. Suzuki, M. Koizumi, T. Nakamura, M. Okuno, N. Inabe, S.
Hamada, Y. Fukashiro, H. Sunaoshi,
M. Wada, T. Kohmoto, T. Kubo, T.
Shinozuka, K. Asahi, T. Inamura, M.
Ishihara, and M. Fujioka: "RadiationDetected Optical Pumping in Solids",
ibid., p. 223.
7) T. Doke, J. Kik~chi, N. Hasebe, H.
Murakami, A. Nakamoto, T.
Yanagimachi, T. Kohno, K. N aga ta ,B. Wilken, K. Maezawa, Y. Muraki,
T. Terasawa, S. Yanagita, K. Munakata, and A. Nishida: "High Energy
Particle Experiment (HEP)", Geotail
Prelaunch Report, ISAS SES - TD92-007SY, Sagamihara, p. 71 (1992).
8) M. Kodama, T. Kohno, and H. Kanzawa: "Stratospheric Sudden Coolingafter Solar Proton Event over Syowa
Station Antarctica", J. Geomag.
Geoelectr., 44, 361 (1992).
9) M.A. Miah, K. Nagata, T. Kohno,
H. Murakami, A. Nakamoto, N.
Hasebe, J. Kikuchi, and T. Doke:"Spatial and Temporal Features ofO. 64-35 MeV Protons in the Space Station Environment: EXOS-C Observations", ibid., p. 591.
10) K. Ieki, N. Iwasa, Y. Ando, K. Hata,
T. Motobayashi, H. Murakami, M.
Ogiwara, Jian - zhi Ruan (Gen) , S.
Shibuya, S. Shira to, H. Fujiwara, S.
C. Jeong, S.M. Lee, T. Mizota, Y.
N agashima, M. Ogihara, S. Okumura,-190-

Y . H. Pu, and M. Ishihara: "Dynamics
of the Projectile- like Fragment Emission in the 4°Ar+ 209 Bi Reaction at 26
MeV /u- P ' , J. Phys. G: Nucl. Particle
Phys., 18,401 (1992).
11) K. Suzuki and H. Toki: "Flavor SU (4)Baryon and Meson Masses in Diquarkquark Model Using the Pauli-Gursey
Symmetry", Mod. Phys. Lett., A7, 2867
(1992) .
12) A. Kohama, K. Yazaki, and R. Seki:"Nuclear Transparency in the GlauberApproximation", Nucl. Phys., A536,
716 (1992).
13) J. Peter, J. P. Sullivan, G. Bizard, W.
Q. Shen, R. Brou, D. Cussol, M.
Louvel, J. P. Patry, R. Regimbard, J.
C. Stecmeyer, B. Tamain, E. Crema,
H. Doubre, K. Hagel, G.M. Jin, A.
Perhaire, F. Saint-Laurent, Y. Cassagnou, R. Legrain, C. Lebrun, E.
Rosato, R. MacGrath, S.C. Jeong, S.
M. Lee, Y. Nagashima, T. Nakagawa, M. Ogihara, J. Kasagi, and T.
Motobayashi: "Inversion of the Collective Matter Flow in Nucleus- Nucleus
Collisions, Measured with a 47l' Charged
Particle Array", ibid., A538, 75c (1992) .
14) T. Suzuki: "Pion Production in Intermediate Energy Nucleus-Nucleus Collisions", ibid., p .113c.
15) T. Kobayashi: "Projectile Fragmentation of Exotic Nuclear Beams", ibid.,
p.343c.
16) K. Soutome, S. Yamaji, and M.'Sano:"Target-Charge Dependence of the Coulomb Dissociation Cross Section ofllLi", ibid., p.383c.
17) R.N. Boyd, D. Hirata, N. Inabe, T.
Kubo, T. Nakagawa, T. Suzuki, 1.
Tanihata, M. Yanokura, X. X . Bai,
K. Kimura, S. Kubono, S. Shimoura,and H.S. Xu: "The 8Li(4He,n) llB Reaction Cross Section at Low Energies",
ibid., p. 523c.
18) J. Kasagi, K. Furutaka, T. Murakami, A. Yajima, M. Ohshima, S.
Niiya, H. Tominaga, K. Yoshida, H.
Hama, K. Ieki, W. Galster, K. Kubo,
M. Ishihara, and A. Galonsky: "Excitation Energy and Spin Dependence of theGiant Dipole Resonance at Finite Temperature", ibid., p.585c.
19) K. Tanaka and W. Bentz: "1/ N Expansion and the Correlation Energy of
Nuclear Matter in the Relativistic (fcuModel", ibid., A540, 383 (1992).
20) R.N. Boyd, S. Kubono, N. Ikeda, M.
Y. Tanaka, T. Nomura, Y. Fuchi, H.
Kawashima, M. Ohura, H. Orihara,
S. Yun, H. Toyokawa, M. Yosoi, and
H. Ohnuma: "9Be(a ,p) 12B Reaction andPrimordial Nucleosynthesis", ibid.,
A542 , 97 (1992).
21) M. Arima, K. Shimizu, K. Yazaki: "AStudy of n-Nucleon S-Wave Resonances and the ll-Nucleon Interaction",
ibid., A543, 613 (1992).
22) T. Sakai, A. Buchmann, K. Yazaki,
and K. Shimizu: "The Nucleon-H-Particle Interaction in the Quark Model",ibid., p.661.
23) M. Oshima, Y. Gono, T. Murakami,
H. Kusakari, M. Sugawara, S. Ichikawa, Y. Hatsukawa, T. Morikawa,
and B.J. Min: "Observation of Coulomb
Excitation of Unstable Nuclei: Utilization of a Secondary Beam", Nucl. Instrum. Methods Phys. Res., A312 , 425(1992) .
24) M. Koizumi, Y. Yoshida, K. Morita,
M. Takami, T. Inamura, M. Azuma,
H. Katsuragawa, M. Nakaoka, I.
Nakamura, T. Ishizuka, T. Murayama, A. Iivonen, K. Valli, K.
Shimomura, S. Matsuki, and I. Sugai:"Velocity Distribution of Ion Beams
from the RIKEN IGISOL", ibid., A313,
1 (1992).
25) H. Ichinose, T. Doke, A. Hitachi, J.
Kikuchi, K. Masuda, and E. Shibamura: "Energy Resolutions for GammaRays and Electrons from 207Bi in Liquid
Xe Doped with TEA", ibid., A322 , 216(1992) .
26) T. Matsuzaki, R. Kadono, K. Ishida,
A. Matsushita, and K. Nagamine:"Low Energy Unstable Nuclear Beam
Channel 'SLOW' at the RIKEN Ring
Cyclotron", ibid., B70, 101 (1992).
27) A. Iivonen, J. Kuhalainen, R.
Saintola, K. Valli, T. Inamura, M.
Koizumi, K. Morita, and A. Yoshida:"The Squeezer Ion Guide", ibid., p. 213.
28) T. Inamura, M. Koizumi, K. Morita,
A. Yoshida, M. Takami, T. Ishizuka,
I. Nakamura, M. Nakaoka, T. Murayama, I. Sugai, M. Azuma, H. Katsuragawa, K. Shimomura, S. Matsuki, A.
Iivonen, and K. Valli: "Velocity Distribution of RIKEN IGISOL Ion Beams",
ibid., p. 226.

-191-29) K. Matsuta, A. Ozawa, Y. Nojiri, T.
Minamisono, M. Fukuda, A. Kitagawa, S. Momota, T. Ohtsubo, Y.
Matsuo, H. Takechi, S. Fukuda, I.
Minami, K. Sugimoto, I. Tanihata, K.
Ornata, S. Shimoura, J .R. Alonso, G.
F. Krebs, and T.J.M. Symons: "AFragment Separator at LBL for the
Beta-NMR Experiment", ibid., p.304.
30) T. Kubo, M.Ishihara, N. Inabe, H.
Kumagai, I. Tanihata, K. Yoshida, T.
Nakamura, H. Okuno, S. Shimoura,
and K. Asahi: "The RIKEN Radioactive
Beam Facility", ibid., p. 309 .
31) K. Ishida, T. Matsuzaki, and K.
Nagamine: "A Large Solid-angle Secondary-beam Collector Using Axially
Symmetric Superconducting Magnetic
Field", ibid., p. 366.
32) K. Shimomura, I. Ogawa, K. Suzuki,
S. Hamada, T. Nakamura, H. Okuno,
M. Koizumi, N. Inabe, Y. Fukashiro,
H. Sunaoshi, M. Wada, S. Hatori, T.
Murayama, T. Kohmoto, Y. Fukuda,
T. Kubo, T. Shinozuka, K. Asahi, S.
Morinobu, T. Inamura, M. Ishihara,
M. Fujioka, M. Kondo, and S. Matsuki: "OPERA: An . On-line System of
Optical Pumping in Solids for Unstable
Nuclei", ibid., p. 513.
33) S. Kubono, Y. Funatsu, N. Ikeda, M.
H. Tanaka, T. Nomura, H. Orihara,
S. Kato, M. Ohura, T. Kubo, N.
Inabe, T. Ichihara, M. Ishihara, I.
Tanihata, H. Okuno, T. Nakamura,
S. Shimoura, H. Toyokawa, C.C.
Yun, H. Ohnuma, K. Asahi, A. Chakrabarti, T. Mukhopadhyay, and T.
Kajino: "Proton Decay Measurementwith RIPS for Astrophysical Interest",
ibid., p.583.
34) G. Bizard, D. Durand, A. GenouxLubain, M. Louvel, R. Bougault, R.
Brou, H. Doubre, Y. EI-Masri, H.
Fugiwara, K. Hagel, A. Hajfani, F.
Hanappe, S. Jeong, G.M. Jin, S.
Kato, J.L. Laville, C. Le Brun, J.F.
Lecolley, S. Lee, T. Matsuse, T.
Motobayashi, J. P. Patry, A. Peghaire, J. Peter, N. Prot, R. Regimbart,
F. Saint- Laurent, J .C. Steckmeyer,
and B. Tamain: "Three Fragment
Sequential Decay of Heavy Nuclei
around 3 MeV lu Excitation Energy",
Phys. Lett. B, 276, 413 (1992).
35) K. Matsuta, A. Ozawa, Y. Nojiri, T.

Minamisono, S. Fukuda, A. Kitagawa, S. Momota, T. Ohtsubo, Y.
Matsuo, H. Takechi, S. Fukuda, I.
Minami, K. Sugimoto, I. Tanihata, K.
Ornata, J .R. Alonso, G.F. Krebs, and
T . J . M. Symons: "Observation of Spin
Polarization of Projectile Fragmentsfrom 106 A MeV 40Ca + Au Collisions",
ibid., 281, 214 (1992).
36) K. Yuasa-Nakagawa, Y.H. Pu, S.C.
Jeong, Y. Futami, T. Mizota, S . M .
Lee, T. Nakagawa, B. Heusch, K.
Ieki, and T. Matsuse: "Complex Fragment Distributions in 84Kr + 27 Al at
E 1ab =10.6 MeV/u", ibid., 283, 185(1992) .
37) H. Hofmann, S. Yamaji, and A.S.
Jensen: "Distribution of Strength for
Isoscalar Modes at Finite Temperature", ibid., 286, 1 (1992).
38) H. Kawakami, S. Kato, T. Ohshima,
C. Rosenfeld, H. Sakamoto, T. Sato,S. Shibata, J. Shirai, Y. Sugaya, T.
Suzuki, K. Takahashi, T. Tsukamoto,
K. Ueno, K. Ukai, S. Wilson, and Y.
Yonezawa: "High Sensitivity Search fora 17 keY Neutrino. Negative Indication
with an Upper Limit of 0.095%", ibid.,
287, 45 (1992) .
39) I. Tanihata, T. Kobayashi, T. Suzuki, K. Yoshida, S. Shimoura, K.
Sugimoto, K. Matsuta, T. Minamisono, W. Christie, D. Olson, and H.
Wieman: "Determination of the Density
Distribution and the Correlation of Halo
Neutrons in 11Li" , ibid., p.307.
40) I. Tanihata, D. Hirata, T. Kobayashi,
S. Shimoura, K. Sugimoto, and H.
Toki: "Revealing of Thick Neutron
Skins in Nuclei", ibid., 289, 261 (1992).
41) R. N. Boyd, I. Tanihata, N. Inabe, T.
Kubo, T. Nakagawa, T. Suzuki, M.
Yanokura, X.X. Bai, K. Kimura, S.
Kubono, S. Shimoura, H. S. Xu, and
D. Hirata: "Measurement of the 8Li (a,n) 11B Reaction Cross Section at
Energies of Astrophysical Interest",
Phys. Rev. Lett., 68, 1283 (1992).
42) F. V. De Blasio, W. Cassing, M. Tohyama, P. F. Bortignon, and R. A. Broglia: "N on- perturbative Study of theDamping of Giant Resonances in Hot
Nuclei", ibid., p.1663.
43) R. Brockmann and H. Toki: "Relativistic Density Dependent Hartree
Approach for Finite Nuclei", ibid.,-192-

p.3408.
44) R. N. Boyd and I. Tanihata:"Physics
with Radioactive Nuclear Beams",
Physics Today, June, p.44 (1992).
45) K. Soutome, S. Yamaji, and M. Sano:"Coulomb Dissociation of the WeaklyBound Nucleus 11 Li", Prog. Theor .
Phys., 87, 599 (1992).
46) T. Watabe and H. Toki: "The Chiral
Quark-soliton Model for the Nucleon",
ibid., p.651.
47) H. Toki and K. Suzuki: "Scale Invariant N ambu and J ona - Lasinio Modelwith Confinement for Hadrons", ibid.,
p.1435.
48) K. Soutome, S. Yamaji, and M. Sano:"Role of Minimum Momentum Transfer
in Coulomb Dissociation of 11 Li Projectiles", ibid., 88, 703 (1992).
49) A. Hosaka and H. Toki: "Chiral Bag
Model", ibid., Suppl., 109, 137 (1992).
50) K. Nagata and HEP Group: "Calibration Experiment of GEOT AIL HighEnergy Particle Observation", Solar
Terr. Environ. Res. jpn., 15, 40 (1992) .
51) S. Kubono, Y. Funatsu, N. Ikeda, M.
H. Tanaka, T. Nomura, H. Orihara,
S. Kato, M. Ohura, T. Kubo, N.
Inabe, T. Ichihara, M. Ishihara, I.
Tanihata, H. Okuno, T. Nakamura,
S. Shimoura, H. Toyokawa, C. C.
Yun, H. Ohnuma, K. Asahi, A. Chakrabarti, T. Mukhopadhyay, and T.
Kajino: "Study of the Decay Property of
2°N a for the Onset Mechanism of the
Rapidproton Process", Radioactive
Nuclear Beams 1991, lOP Publishing,p.317 (1992).
52) S. Kubono, N. Ikeda, M. H. Tanaka,
T. Nomura, 1. Katayama, Y. Fuchi,
H. Kawashima, C.C. Yun, Y. Tajima,
M. Yosoi, H. Ohnuma, M. Ohura, T.
Kubo, 1. Tanihata, H. Toyokawa, H.
Orihara, H. Miyatake, T. Shimoda, R.
N. Boyd, and T. Kajino:"Experimantal
Study of the Key Reaction 8Li( a, n) 11 B
for the Primordial N ucleosynthesis" ,ibid., p. 323.
53) T. Wada, N. Carjan, and Y. Abe:
"Multi - Dimensional LangevinApproach to the Dissipative Dynamics
of Nuclear Fission", Proc. Tours
Symp. on Nucl. Phys., World Scientific, Singapore, p .136 (1992).
54) I. Tanihata: "Studies with Radioactive
Beams-Preperties of Neutron Halo-",ibid., p .150.
55) K. Soutome, S. Yamaji, and M. Sano:"Target- Charge Dependence of the Coulomb Dissociation Cross Section of the
Weakly-Bound Nucleus 11Li", Proc. ofInt. Symp. on Structure and Reactionsof Unstable Nuclei, Niigata, Japan,
1991, World Scientific, Singapore,p .167 (1992).
56) T. Kobayashi: "Spectroscopy of the
Exotic Nucleus 11 Li via Pion Double
Charge Exchange Reaction lIB (7(- ,7( +) llLi" , ibid., p.187.
57) 1. Tanihata: "On the Momentum Distributions of Fragments of 11 Li and 11 BePossible Indication of di-Neutron Formation- ", ibid., p. 233.
58) H. Sato: "Nucleus as a CanonicalEnsemble", Proc. Int. Workshop on
Gross Properties of Nuclei and Nuclear
Excitations XX, GSI, Darmstadt, p.89
(1992) .
59) T. Kobayashi: "Spectroscopy of the
Exotic Nucleus 11Li via Pion Double
Charge Exchange Reaction 11B (7( - , 7(+)
11 Li", Proc. Int . Workshop on Pions in
Nuclei, Peniscola, Spain, 1991, Edited
by T . Osset, W or ld Scientific, Singap ore , p. 58 (1992).
60) S. Hirenzaki, H. Toki, and T. Yamazaki: "Formation of Deeply Bound
Pionic Atoms", ibid., p. 345.
61) H. Sato: "Nucleus as a CanonicalEnsemble: Level Density", Proc. Specialists' Meet. on High Energy Nuclear
Data JAERI-M92-039 (JEARI, 1992),
p .162 (1992).
62) H. Sato: "Nucleus as a CanonicalEnsemble: Deformed Nucleus", Proc. of
the Symp. on Group Theory and Special
Symmetries in Nuclear Physics, World
Scientific, Singapore, p. 359 (1992).
3. Atomic and solid-state physics

1) 1. Shimamura: "R- Matrix Method andDoubly Excited Rydberg States", Adv.
in Atomic and Molecular Physics, ed.
M.S.Z. Chaghtai, Today & Tomorrow's Printers and Publishers, New Delhi,
p.17 (1992).
2) A. Matsushita, R. Kadono, K. Nishiyama, Y. Miyake, A. Nakao, J. Takahashi, M. Iwaki , and K. N agamine:"Muonium Formation on Powdered
Platinum Surface", Chem. Phys. Lett.,
197, 297 (1992).

- 193-

3) M. Sakurai, T. Sekioka, M. Kimura,T. Niizeki, T. Hirayama, M. Terasawa, H. Yamaoka, Y. Awaya, J.
Yoda, A. Ogata, and S. Ohtani: "Storage and Lifetime Measurements of Multiply Charged Ions Produced by
Synchrotron Radiation" , lPn. l. Appl.
Phys., 30, 1899 (1991).
4) S.C. Mukherjee, D. P. Sural, J.F.
McCann, and I. Shimamura: "Theory ofElectron Capture in Ion-Atom Collisions
at High Energies", Comments At. Mol.
Phys., 28, 25 (1992).
5) P. Hvelplund, H. Tawara, K. Komaki, Y. Yamazaki, K. Kuroki, H.
Watanabe, K. Kawatsura, M. Sataka,
M. Imai, Y . Kanai, T. Kambara, and
Y . A waya: "Binary Encounter Peaks for
0° Electrons in Collisions between 2
Me V / amu Si q + and He", l. Phys. Soc.
lPn., 60, 3675 (1991).
6) K. Tanaka, E. Yagi, K. Kawakami,
and A. Ono: "Channeling Analysis of Ge
Epitaxial Layer on Si Substrate and
Doped Ga Atoms by Using RBS andPIXE Methods", Int. l. PIXE, 2, 137(1992) .
7) E. Yagi: "Behaviour of Kr Atoms in KrImplanted Aluminium", Ionics, (in J apanese), 18, No.2, p.3 (1992).
8) H. Tawara, T. Tonuma, H.
Kumagai, and T. Matsuo: "Multiply Charged Ions Produced from Condensed
Gas Targets under Heavy Ion Impact:
Comparison between Atom and Molecule Targets", l. Phys. B: At. Mol.
Opt. Phys., 25, L423 (1992).
9) T. Mizogawa, Y. Awaya, Y. Isozumi,
R. Katano, S. Ito, and N. Maeda:"New Readout Technique for TwoDimensional Position-Sensitive Detectors" , Nucl. Instrum. Methods Phys.
Res., A312 , 547 (1992).
10) M. Imai, M. Sataka, H. Naramoto,Y. Yamazaki, K. Komaki, K. Kawatsura, and Y. Kanai: "Dynamical
Behaviour of Angular Momentum Distributions of Autoionizing Is22pnl
States of Sl2+ Ions Excited through Carbon Foils", ibid., B67, 142 (1992).
11) T. Tonuma, H. Kumagai, T. Matsuo,
H. Shibata, and H. Tawara: "Molecular and Cluster Ions Produced from
Frozen C2H 2 Molecules under Energetic, Heavy Ion Impact", ibid., p. 544.
12) T. Okada, M.D. Lan, J.Z. Liu, R.N.

Shelton, and K. Asai: "Mossbauer
Studies of Single Crystal YBa2Cu3 - XFeX
0 7 - / ' , Physica C, 185-189, 783 (1991).
13) T. Okada, Y. Kobayashi, K. Asai, N.
Yamada, and T. Yamadaya: "s7Fe
Mossbauer Studies of BiPbSr2FeOs",
ibid., p .1125.
14) M. Sataka, K. Kawatsura, H. Naramoto, Y. Nakai, Y. Yamazaki, K.
Komaki, K. Kuroki, Y. Kanai, T.
Kambara, Y. Awaya, J .E. Hansen, I.
Kadar, and N. Stolterfoht: "High-resolution L-shell Auger Spectroscopy of
Mg-like Scandium Produced in 89MeV
Sc 8 + + He Collisions", Phys. Rev. A,
44, 7290 (1991).
15) M. R. Harston, I. Shimamura, and M.
Kamimura: "Energy Shift in the [(dt,u)dJee Molecule Due to the Finite Size of
the Muonic Molecular Ion (dt,u) +",ibid., 45,94 (1992).
16) A. Igarashi and N. Toshima: "Destructive and Constructive Interferences of
the Second Born Amplitudes for
Positronium Formation", ibid., 46, 1159
(1992) .
17) I. Shimamura: "Scaling of the Cross
Sections for Vibrational Transitions",
ibid., p .1394.
18) N. Toshima and J. Eichler: "Nonperturbative Treatment of the Thomas Mechanism in Electron Capture", ibid., p. 2564 .
19) I. Shimamura: "Moleculelike Metastable States of Antiprotonic and Mesic
Helium", ibid., p. 3776.
20) H. Fukuda and T. Ishihara: "Distorted
Atomic-Orbital Expansion for Slow IonAtom Collisions", ibid., p. 5531.
21) R. Kadono, A. Matsushita, K. Nishiyama, and K. Nagamine: "MuonInduced Luminescence in KBr", Phys.
Rev. B, 46, 8586 (1992).
22) K. Ando, U .1. Safronova, and I. Y.
Tolstikhina: "Energy Levels 1s221nl'(n=2, 3, 4) of Na VIII-S XIII Ions.
Comparison of Two Calculation
Methods: MCDF and MZ", Phys. Scr.,
46, 107 (1992).
23) E. Yagi: "Channelling Experiments on
the Lattice Location of Hydrogen in
Metals by Using a Nuclear Reaction IH(l1B,a) all''',Yoda, A. Ogata, and S. Ohtani: "Trapping and Probing of Multiply Charged
Xe Ions Produced by Synchrotron Radiation", Rev. Sci. Instrum., 63, 1186
(1992) .
25) S. Kravis: "SPring-8 Workshop on
Atomic Physics", Synchrotron Radiat.
News, 5, 3 (1992).
26) H. Tawara, T. Tonuma, H.
Kumagai, T. Matsuo, and H. Shibata:"Multiply-Charged Ions and Cluster
Ions Produced from Frozen CO 2 andH 20 Targets in Energetic, Heavy Ion
Impact", Z. Phys. D, At. Mol. andClusters, 21, S257 (1991).
27) T. Kambara, R. Schuch, Y. A waya ,T. Mizogawa, H. Kumagai, Y. Kanai,
H. Shibata, and K. Shima: "Solid-gas
Effect in K - Vacancy Production in
Near Symmetric Slow Heavy- Ion-Atom
Collisions", ibid., 22, 451 (1992).
28) M. R. Harston, I. Shimamura, and M.
Kamimura: "Energy Shift in (dt,u) e Dueto the Finite Size of the Muonic Molecular Ion (dt,u) +", ibid., p. 635.
4. Radiochemistry radiation chemistryradiation biology

Rad. Ell. Del. Sol.,

124, 21 (1992).
24) M. Sakurai, M. Kimura, T. Sekioka,
M. Terasawa, H. Yamaoka, T. Niizeki , Y. A waya , T. Hirayama, J.

-194-

I

I

and

1) M. Iwamoto, Y. Kobayashi, S. Y.
Chen, Y. Ohkubo, S. Ambe, M. Yanokura, A. N . Garg, and F. Ambe: "Separation of Multitracers from Heavy-IonIrradiated Targets by Melting under
Reduced Pressure", Anal. Sci., 7,
Suppl., 313 (1991).
2) S. Ambe, S. Y. Chen, Y. Ohkubo, Y.
Kobayashi, M. Iwamoto, M. Yanokura, and F. Ambe: "Preparation ofRadioactive Multitracer Solutions from
Au, Ag, and Cu Foils Irradiated withHigh - Energy Heavy Ions", ibid., p. 317 .
3) S.Y. Chen, S. Ambe, Y. Ohkubo, M.
Iwamoto, Y. Kobayashi, N. Takematsu, and F. Ambe: "Study ofRemoval Mechanisms of Metal Elements from Seawater Using Radioactive
Multitracers", ibid., p .1105.
4) T. Takahashi, F. Yatagai, and K.
Izumo: "Microdosimetric Considerations of Effect of Heavy Ions on E. coli
K -12 Mutants", Adv. Space Res., 131,
No.2, p.65 (1992).
5) S. Ambe, Y. Ohkubo, Y. Kobayashi,
M. Iwamoto, M. Yanokura, and F.
Ambe: "Preparation of Radioactive
Multitracer Solutions from a High-Energy Heavy-Ion Irradiated Au Target by Means of a Supported Liquid
Membrane", Appl. Radiat. Isot., 43,1533 (1992).
6) M. Nakada, Y. Watanabe, K. Endo,
H. Nakahara, H. Sano, K. Mishima,
M.K. Kubo, Y. Sakai, T. Tominaga,
K. Asai, I. Kohno, and F. Ambe:"Mossbauer Emission Spectroscopy of
57Fe Arising from 57Mn in Metal andOxides of Chromium", Bull. Chem.
Soc. lPn., 65, 1 (1992).
7) S. Ambe, S. Y. Chen, Y. Ohkubo, Y.
Kobayashi, M. Iwamoto, and F. Ambe:"Application of the Radioactive
Multitracer Technique to a Study ofAdsorption of Metal Ions on a-Fe 2 03",
Chem. Lett., 1992, 1059.
8) Y. Ohkubo, Y. Kobayashi, S. Ambe,
K. Harasawa, M. Takeda, S. Shibata,K. Asai, T. Okada, and F. Ambe:"99Ru (+-99Rh) as a TDP AC Probe in the
Study of a High-Tc Superconductor",
ibid., p. 2069 .
9) Y. Kobayashi, M. Watanabe, M.
Katada, H. Sano, T. Okada, and F.
Ambe: "99Ru Mossbauer Spectroscopic
Studies on Salts of Ruthenocene with
Halogens", Hyperfine Interact., 68, 189(1991) .
10) J. S. Zheng, Y. Kobayashi, J. Nakamura, K. Asai, G. L. Zhang, and F.
Ambe: "Europium-151 Mossbauer EffectStudy of Europium Orthovanadite",
ibid., p. 307.
11) J. Nakamura, Y. Kobayashi, F.
Ambe, K. Asai, and N. Yamada: " 121 Sb
Mossbauer Spectroscopy of Mnl+xSb",
ibid., p.311.
12) G.L. Zhang, S. Y. Chen, S. Ambe, K.
Maeda, K. Suzuki, Y. Sasa, E. Yagi,
H. Yabuki, Z.W. Huang, and F.
Ambe: "Characterization of Iron Oxides
and Hydroxides in the Sand of Flaming
Mountain", ibid., 70, 973 (1992).
13) T. Nagamune, J. Honda, Y. Kobayashi, H. Sasabe·, I. Endo, F.
Ambe, Y. Teratani, and A. Hirata:"Mossbauer, Electron Paramagnetic
Susceptibility Studies of Photosensitive
Nitrile Hydratase from Rhodococcus sp.
N-771", ibid., 71, 1271 (1992).
14) Y. Kobayashi, T. Okada, K. Asai, M.
Katada, H. Sano, and F . Ambe: "Mossbauer Spectroscopy and Magnetization
Studies of a- and ,B-RuCI 3 " , lnorg.

-195-

Chem., 31, 4570 (1992).
15) M. Suzuki, M. Watanabe, K. Nakano, K. Suzuki, and K. Matsui: "Heavyion - Induced Chromosome Breakage
Studied by Premature Chromosome
Condensation (PCC) in Syrian Golden
Hamster Embryo Cells", Int. l.
Radiat. Biol., 62, 581 (1992).
16) M . Watanabe, M. Suzuki, K. Suzuki,
K. Nakano, and K. Watanabe: "Effectof Multiple Irradiation with Low Doses
of Gamma - Rays on MorphologicalTransformation and Growth Ability of
Human Embryo Cells in vitro", ibid.,
p.711.
17) F. Yatagai, M.J. Horsfall, and B.W.
Glickman: "Specificity of SOS
Mutagenesis in Native M13 lacl
Phage" , J. Bacteriol., 173, 7996 (1991) .
18) O. Yatou and T. Takahashi: "Evaluation of Mutation Induction Effect of Ion
Irradiation in Soybean Strain L65 with
the Heterozygous Leaf Color Locus
yl1. ", Jpn. l. Breeding, 42, Suppl., 2,
p.472 (1991).
19) M. Watanabe, M. Suzuki, K. Suzuki,
K. Nakano, and F. Yatagai: "Radiation-Induced Chromosome Damage in
G1 - Phase Cells as Breaks in Premature
Chromosome Condensation (PCC) andAnalysis of Its Biological Meaning" , 1 .
Radiat. Res., 33, 87 (1992).
20) F. Yatagai, S. Hachiya, Y. Hama, A.
J . E. Gordon, and F. Hanaoka: "Resolution and Characterization of Polymorphic DNA by SSCP and Chemical Cleavage Methodologies", ibid., p. 95.
21) F. Yatagai, J.A. Halliday, and B.W.
Glickman: "Specificity of recA 441Mediated (tif -1) Mutational Events",
Mol. Gen. Genet., 230, 75 (1991).
22) K. Kimura: "Track-depth Resolved
Dynamics of Helium Excimers along 4
in Near-liquid and Liquid Helium",Proc. Int. Coni. on Liquid Radiation
Detectors: Their Fundamental Properties and Applications, p. 38 (1992).
23) Y. Itoh, H. Murakami, and T. Suzuki:"Defects in Electron or Proton Irradiated U ndoped and Si -doped GaAs by
Positron Annihilation", Positron Annihilation Proc. 9th Int. Coni. Positron
Annihilation, Materials Science
Forum, Trans Tech Publications, Switzerland, 105-110, 1085 (1992).

5. Material analysis
1) K. Tazaki, T. Tiba, M. Aratani, and
M. Miyachi: "Structural Water in Volcanic Glass", Clays and Clay Minerals,
40, 122 (1991).
2) K. Maeda, Y. Sasa, and M. Uda:
"High Resolution Soft X - Ray
Spectrometer for Chemical State Analysis by PIXE" , Int. l. PIXE, 2, 19(1992) .
3) M. Suzuki and T. Takahashi: "Proportional Scintillation Imaging Chamberand Its Application", Ioniz. Radiat.,
On Japanese), 19, 54 (1992).
4) K. Tazaki, M. Aratani, M. Yanokura, K. Kaiho, and S. Noda: "Singularity of Clay Minerals and Iridium
Concentration at Cretaceous- Tertiary-196-(K - T) Boundary", l. Clay Sci. Soc.

lPn., 32, 86 (1992).
5) 1. Sugai, M. Oyaizu, M. Aratani, M.
Yanokura, and K. Yamazaki: "Development of Heavy Ion Beam Sputtering
Method for Long-Lived Carbon Stipper
Foils", Nucl. Instrum. Methods Phys.
Res., A320, 15 (1992).
6) K. Maeda and J. Kawai: "Report on 6th
Int. Conf. on PIXE and 1st Int. Symp.
on Bio-PIXE", Oyo Buisuri (in Japanese),61, 1180 (1992).
7) J. Kawai, M. Takami, M. Fujinami,
Y. Hashiguchi, S. Hayakawa, and Y.
Gohshi: "A Numerical Simulation of
Total Reflection X-Ray Photoelectron
Spectroscopy (TRXPS)", Spectrochim.
Acta, 47B, 983 (1992).

VIII. LIST OF PREPRINTSVIII. LIST OF PREPRINTS
1992
RIKEN-AF-NP
119

I. Tanihata, T. Kobayashi, T. Suzuki, K. Yoshida, S. Shimoura, K. Sugimoto, K. Matsuta,
T. Minamisono, W. Christie, D. Olson, and H. Wieman: "Determination of the Density
Distribution and the Correlation of Halo Neutrons in llLi"

120

T. Harada: "Production and Structure of Light ~ - Hypernuclei"

121

H. Toki and K. Suzuki: "Scale Invariant Nambu and lona- Lasinio Model with Confinement for
Hadrons"122

V . V. Lyukov and N . I. Starkov: "Properties and Some Production Possibilities of the Charmed
Nuclei"123

I. Tanihata, D. Hirata, T. Kobayashi, S. Shimoura, K. Sugimoto, and H. Toki: "Revealingof Thick Neutron Skins in Nuclei"

124

T. Yamada and K. Ikeda: "!He Hypernuclear States and Roles of the Spin- Isospin Terms of~- N Interaction"

125

T. Yamada and K. Ikeda: "Possible Existence of a Bound State in XLi"

126

C. -B. Moon, M. Fujimaki, S. Hirenzaki, N. Inabe, K. Katori, J.C. Kim, Y.K. Kim, T.
Kobayashi, Y. Kubo, H. Kumagai, S. Shimoura, T. Suzuki, and I. Tanihata: "Measurements of llLi +p and 9Li +p Elastic Scatterings at 60 MeV"

127

S. Hirenzaki, H. Toki, and I. Tanihata: "Proton Elastic Scattering with 9Li and llLi and its
Halo Structure"

128

K. Yoshida, J. Kasagi, H. Rama, M. Sakurai, M. Kodama, K. Furutaka, K. leki, W.
Galster, T. Kubo, M. Ishihara, and A. Galonsky: "Neutron Emission for the Fusion of 40 Ar +Ni, 92Mo, 122 Sn Reactions at E/A=26 MeV"129

H . T. Duong, C. Ekstrom, M. Gustafsson, T. T. Inamura, and P. J uncar: "A tomic Beam
Magnetic Resonance Apparatus for Systematic Measurement of Hyperfine Structure Anomalies(Bohr-Wesskope Effect)"130

Y. Yamamoto, M. Wakai, T. Fukuda, and M. Sano: "Formation of Double-Lamda Hypernucleus from Quasi- Free 8 Absorption"

131

K. Sugimoto and I. Tanihata: "Nuclear Structures Studied with Exotic Nuclear Beams"

132

A. Ozawa: "Projectile-Fragmentation Process Studied by Detecting the Spin Polarization of
Heavy Fragments of 100 MeV/nucleon (thesis)"133

C. - B. Moon, M. Fujimaki, N. Inabe, K. Katori, J .C. Kim, T. Kobayashi, T. Kubo, H.
Kumagai, S. Shimoura, T . Suzuki, and I. Tanihata: "Measurement of Angular Distribution
for the llLi +p and 9Li Elastic Scatterings"
I. Tanihata, D. Hirata, T. Kobayashi, S. Shimoura, K. Sugimoto, and H. Toki: "Revelationof Thick Neutron Skin in Nuclei"-197-

T. Kobayashi: "Nuclear Structure Experiments on llLi"
I. Tanihata: "Radioactive Beam Facilities and Their Physics Program"
134

S. Shimoura, T. Nakamura, H. Okamura, H. Okuno, H. Sakai, and M. Ishihara: "Density
Distribution of Neutron Halo in llLi"

135

H. Okuno, K. Asahi, H. Veno, H. Sato, M. Adachi, T. Kubo, T. Nakamura, N. Inabe, A.
Yoshida, Y. Ohkubo, T. Ichihara, M. Ishihara, T. Shimoda, H. Miyatake, and N. Takahashi: "Polarization in Projectile Fragmentation and g-Factor Measurements for Neutron-Rich
Nuclei"136

K. Kato and K. Ikeda: "Analyses of 9Li+n Resonances in IOLi by the Complex Scaling
Method = Interaction between 9Li and Neutron"

137

B. V. Danilin, A. A. Korsheninnikov, and M. V. Zhukov:
Narrow Three- Body Resonance"

138

Y. Futami, T. Mizota, Y.H. Pu, Y. Honjo, K. Yuasa-Nakagawa, H. Toyokawa, S.M.
Lee, K. Furutaka, T. Murakami, J. Kasagi, K. Yoshida, and T. Nakagawa: "Performanceof a Phoswich Detector Composed of a Thin Plastic and a Thick BaF 2 Scintillators"

139

M. Sano, K. Soutome, and S. Yamaji: "Projectile Fragmentation in Heavy- Ion Collisions"

140

S. Yamaji, A.S. Jensen, and H. Hofmann: "Isoscalar Vibrational States in Hot Nuclei"- 198-"Possible Existence of IOHe as

IX. PAPERS PRESENTED AT MEETINGSIX. PAPERS PRESENTED AT MEETINGS
tions, Vancouver, Canada, July (1992) .
9) Y. Yano: "Status Report on RIKEN
Accelerator Research Facility", RIKEN
Int. Symp. on Unstable Nuclei andParticles as Probes in Physics andChemistry, Wako, Aug. (1992).
10) Y. Yano: "RIKEN Accelerator
Research Facility (RARF) " , Joint
Italian - Japanese Meet. within the
INFN - RIKEN Agreement 'Perspectives
in Heavy Ion Physics', Catania, Italy,
Sept. (1992).
11) J. Ohnishi: "Magnetic Field Measurements with Harmonic Coils", Autumn
Meet. Phys. Soc. Jpn., Niigata, Oct.
(1992) .
12) H. S. Sakaue, Y. Hirano, S. R. In, S.
Y okouchi, K. Watanabe, and S. H. Be:"Lumped NEG Pump for Crotch andPumping System of SPring-8 Storage
Ring" ,12th Int. Vacuum Congr.,
Hague, the Netherlands, Oct. (1992).
13) Y. Yano: "RARF and Other New Ion
Accelerator Facilities in Japan", Joint
Symp. on Synchrotron Radiation
Sources, Pohang, Korea, Nov. (1992).

1. Accelerator development and accelerator
physics

1) A. Goto:"Acceleration of Proton Beams
with RIKEN Ring Cyclotron", The Specialists' Meet. on High Energy Nuclear
Data, Tokai, Oct. (1991).
2) S. Yokouchi, Y. Hirano, K.
Watanabe, S.R. In, and S.H. Be:"Pumping Speed of a Distributed NEG
Strip", 8th Meet. on Ultra High V acuum Techniques for Accelerators andStorage Rings, Tsukuba, Mar. (1992).
3) K. Watanabe, Y. Oikawa, H.A. Sakaue, S. Takahashi, C.Y. Xu, T.
Hanasaka, Y. Hirano, S.H. Be, S.
Yokouchi, T. Nishidono, and R. S. In:"Vacuum System for SPring-8 Storage
Ring", ibid.
4) H. A. Sakaue, Y. Oikawa, S. Takahashi, C. Y. Xu, T. Hanasaka Y. Hirano, S.H. Be, S. Yokouchi, and K.
Watanabe: "Pumping System for
SPring-8 Storage Ring", ibid.
5) Y. Hasegawa, H. Yuta, F. Suekane,
T. Kondo, Y. Unno, H. Iwasaki, Y.
Sakai, Y. Watanabe, T. Tanimori, K.
Kaneyuki, L. Soso, T. Doke, A. Hitachi, T . Ito, E. Shibamura, K.
Masuda, and T. Takahashi: "Photoionization of Dopants in Liquid ArgonXenon Mixture", Int. Conf. on Liquid
Radiation Detectors, Tokyo, Apr.
(1992) .
6) N. Ishida, T. Doke, J. Kikuchi, K.
Kuwahara, T. Kashiwagi, M. Ichige,
K. Hasuike, K. Ito, S. Ben, A . Hitachi, Y.H. Qu, K. Masuda, M. Suzuki,
M. Kase, and T. Takahashi: "Fundamental Test of Liquid Xe and Ar/Xe
Scintillation Detector Using Silicon
Photodiode", ibid.
7) K. Watanabe, S. Takahashi, T.
Hanasaka, Y. Hirano, H. A. Sakaue,
C. Y. Xu, K. Yano, S. Yokouchi, S.
H. Be, N. Ota, Y. Suetsugu, K. Kanazawa, Y. Morimoto, T. Shirakura,
and K. Konishi: "Synchrotron Radiation
Interactions in the Crotch and Absorbers, and Their Design", XVth Int.
Conf. on High Energy Accelerators,
Hamburg, Germany, July (1992).
8) Y. Yano: "Recent Achievements at the
RIKEN Ring Cyclotron", 13th Int.
Conf. on Cyclotrons and their Applica-

2. Nuclear physics and nuclear instrumenta-

-199-

tion

1) M. Hosaka, H. Orihara, M. Ohura, G.
C. Jon, K. Ishii, K. Furutaka , and J.
Kasagi: "Development of BaF 2 y - Ray
Detector", 46th Ann. Meet. Phys. Soc.
J pn., Sapporo, Sept. (1991).
2) K. Hosomi, T. Tohei, T. Nakagawa,J. Takamatsu, A. Terakawa, A. Narita, T. Inomata, H. Orihara, K. Ishii,
M. Ohura, M. Hosaka, G.C. Jon, T.
Suehiro, K. Miura, K. Abe, and H.
Ohnuma: "The 4He, 160 (3He, n) 6Be,
18Ne Reaction at E=45MeV", ibid.
3) A. Narita, T Tohei, T. Nakagawa,
A. Sato, J. Takamatsu, M . Mori, A.
Terakawa, K. Hosomi, H. Orihara,
T. N iizeki, M. Ohura, S. Hirasaki,
M. Hosaka, G.C. Jon, K. Miura, and
H. Ohnuma: "The 42Ca (d, n) Reaction
and the Hole Strenghths of the sdshells", ibid.
4) A. Terakawa, T. Tohei, T. Nakagawa, J. Takamatsu, A. Narita, K.
Hosomi, H. Orihara, K. Ishii, T.
Niizeki, M. Ohura, M. Hosaka, G.C.
Jon, K. Miura, and H. Ohnuma: "Inves-tigation of the Single-Proton States in
19F through the (d, n) Reaction", ibid.
5) H. Toyokawa, Y. Honjo, K. Ohkushi,
N. Tomita, H. Ohnuma, T. Niizeki,
H.Y. Yoshida, Y. Tajima, C.C.
Yoon, M. Yosoi, H. Orihara, M.
Ohura, M. Hosaka, S. Kubono, M.H.
Tanaka, and N. Ikeda: "13C (p, ds=o) 12C
Reaction with 35 MeV Proton", ibid.
6) A. Terakawa, T. Tohei, T. Nakagawa,A. N arita, K. Hosomi, T. Inomata,H. Orihara, K. Ishii, M. Ohura, M.
Hosaka, S. Miyamoto, G.C. Jon, K.
Miura, and H. Ohnuma: "Deuteron
Adiabatic Analysis of the 20sPb (d, n)
209Bi Reaction at Ed = 25 MeV", ibid.
7) S. Hirenzaki, C. - B. Moon, T. Suzuki,
T. Kobayashi, and 1. Tanihata: "An
Optical Model Study of the Li + p Elastic
Scattering", RIKEN Symp. on Nucl.
Phys. by Unstable Nucl. Beam, Wako,
Jan. (1992).
8) K. Soutome, S. Yamaji, and M. Sano:"Nuclear Dissociation of llLi", ibid.
9) M. Koizumi, T. Inamura, T. Ishizuka,
H. Katsuragawa, K. Shimomura, T.
Shinozuka, I. Sugai, M. Takami, Y.
Tagishi, M. N akaoka, 1. Nakamura,T. Horiguchi, S. Matsuki, T. Murayama, K. Morita, A. Yoshida, and M.
Wakasugi : "Laser Spectroscopy with
IGISOL", Symp. on Radiation-detected
Hyperfine Interaction, Osaka, Jan.
(1992) .
10) H. Sato: "The Production Cross Sectionof N uclides-The Mass Distribution of
Fission Products-", RIKEN Symp. on
the Study of Nuclear Structures andReactions with the Unstable Nucleus,
Wako, Jan. (1992).
11) C.-B. Moon: "Angular Distributions forthe 9.11Li +p Elastic Scattering", ibid.
12) T. Wada: "Nuclear Dissipative
Dynamics", RIKEN Symp. on Nuclear
Fusion and Fission Reactions, Wako,
Jan. (1992).
13) S. Date and H. Sumiyoshi: "Event Simulator URASiMA for Ultrarelativistic
Heavy Ion Collisions", RIKEN Symp.
on Physics of High Energy Heavy Ion
Collisions, Wako, Jan. (1992).
14) H. Sato: "Nucleus as a CanonicalEnsemble", Int. Workshop XX on
Gross Properties of Nuclei and Nuclear
Excitations held at Hirsheg, Kleiwalsertal, Austria, Jan. (1992).

. -200-

15) S. Date and H. Sumiyoshi: "Event Simulator: URASiMA", Int. Mini -Symp.
on High-Energy Heavy- Ion Reactions,
Hiroshima, Feb. (1992).
16) S. Date and H. Sumiyoshi: "Event Simulation of High Energy Heavy Ion Collisions based on a Multiple Scattering
Model", 47th Ann. Meet. Phys. Soc.
Jpn., Yokohama, Mar. (1992).
17) N. Ishida, T . Doke, J. Kikuchi, T.
Kashiwagi, M. Ichige, A. Hitachi, K.
Ito, K. Masuda, E. Aprile, M. Suzuki,
and T. Takahashi: "Measurement of the
Attenuation Length of Scintillation
Light in Liquid Xenon", ibid.
18) K. Soutome, S. Yamaji, and M. Sano:"Dissociation Cross Sections of llLi",
ibid.
19) T. Murayama, H.T. Duong, J. Pinard,
T.T. Inamura, and S. Matsuki:"Systematic Measurement of Hyperfine
Structure Anomaly", ibid.
20) F.V. De Blasio, W. Cassing, M. Tohyama, P. F. Bortignon, and R. A. Broglia: "Temperature Dependence of the
Widths of the Giant Resonances", ibid.
21) K. Ishida, T. Matsuzaki, R . Kadono,
A. Matsushita, and K. Nagamine:"Production of Surface Muons by 14N at
135 MeV / A and 4°Ar at 95 MeV/A",
ibid.
22) S. Hirenzaki, C.-B. Moon, T. Suzuki,
T. Kobayashi, and 1. Tanihata: "Proton-Li Elastic Scattering", ibid.
23) S. Ohta: "Lattice QCD Numerical Calculations on Parallel Computer AP 1000",
ibid.
24) T. Wada, N. Carjan, and Y. Abe:
"Light-Particle Emissions In Induced
Nuclear Fission", ibid.
25) K. Shimomura, 1. Ogawa, K. Suzuki,
S. Hamada, T. Nakamura, H. Okuno,
M. Koizumi, N. Inabe, Y. Fukashiro,
H. Sunaoshi, M. Wada, T. Murayama, T. Kohmoto, T. Kubo, T. Shinozuka, K. Asahi, T. Inamura, H. Ishihara' M. Fujioka, and S. Matsuki:"Nuclear Structure Studies of NeutronRich Nuclei with Radiation-Detected
Optical Pumping in Solids", ibid.
26) T. Inamura, M. N akaoka, A. Iivonen,
R. Saintola, K. Valli, J. - H. Gu, and
H. -J . Song: "Measurements of theEnergy Spread of Ion - Guide Beams",
ibid.
27) H. Toyokawa, Y. Honjo, K.Ohkushi,

N. Tomita, H. Ohnuma, T. Niizeki,
H.Y. Yoshida, Y. Tajima, C.C. Yoon,
M. Yosoi , H. Orihara, M. Ohura,
M. Hosaka , S. Kubono, M. H. Tanaka,
and N. Ikeda: " 13C (p, ds=o) 12C Reaction
by 35MeV Proton", ibid.
28) A. Terakawa, T. Tohei, T. Nakagawa, A. Narita, K. Hosomi, T.
Inomata, H. Orihara, K. Ishii, M.
Ohura, M. Hosaka, S. Miyamoto, G.
C. Jon, K. Miura, and H. Ohnuma:"Deuteron Adiabatic Analysis of the
20sPb (d, n) 209Bi Reaction at Ed = 25
MeV", ibid.
29) K. Tanaka and W. Bentz: "Nuclear
Matter Properties including Higher
Order Quantum Corrections II", ibid.
30) M. Kato, W. Bentz, K. Tanaka, andK. Yazaki: "A Modified Nambu- JonaLasinio Model for Mesons and Baryons", ibid.
31) N. Sakamoto: "Analyzing Powers of
12C (d ,p) 13C (g.s.) and 12C (d .do) [Ed=14MeVJ", ibid.
32) H . Sato: "Nucleus as a CanonicalEnsemble: Deformed Nucleus", ibid.
33) T. Inamura: "Atomic Beam Magnetic
Resonance Experiment - for Bohr Weisskopf Effect Measurement withISOLDE at CERN-", Workshop on
Electromagnetic Isotope Separators andtheir Application, Kumatori, Mar.
(1992) .
34) H . Toki: "Scale Invaliant N ambu andJona-Lasinio Model", Int. Symp. on
Extended Objects and Bound Systems,
Karuizawa, Mar. (1992).
35) K. Ishida: "Large Solid-angle Superconducting Muon Channel", Workshop on
Research and Developments for JHP
and Related Scientific Topics, Tanashi,
Mar. (1992).
36) T. Kobayashi: "Experiments with Light
Neutron- Rich Projectiles", Symp. on
Production and Utilization of Radioactive Beams, Am . Chern. Soc. Meet.,
San Francisco, U.S.A., Apr. (1992).
37) A. Iivonen, R. Saintola, K. Valli, T.
Inamura, K. Morita, and A . Yoshida:"Ion - Guide Quadrupole Mass
Spectrometer for On- Line Studies of
Short- Lived Nuclei", Finnish Phys.
Soc. Meet., Lahti, Finland, Apr. (1992).
38) T. Motobayashi: "Nuclear Astrophysics
Studied by Unstable Nuclear Beams",
Ann. Meet. Phys. Soc. Jpn., Tokyo,-201-

Apr. (1992)
39) H. Toki: "Pauli-Gursey Symmetry in
Mesons and Baryons", German-Eastasia Symp. on Symmetries andDynamics in Nuclear and Low-Energy
Particle Physics, Blaubeuren, Germany, May (1992) .
40) K. Yazaki: "Nuclear Transparency inHigh Energy Collisions", 1st J apaneseIsraeli Binational Symp. on Theoretical
Physics, Rehovot , Israel, May (1992).
41) H . Suganuma and T. Tatsumi: "Chiral
Symmetry Restoration in a Strong
Color-Electromagnetic Field and Hadron Structure", RCNP Workshop on
Dynamics of Quarks and Hadrons in
Nuclei, Ibaraki, June (1992) .
42) K. Tanaka and W. Bentz: "Nuclear
Matter Properties including Higher
Order Quantum Corrections in the
Relativistic (J' - (RJ Model", ibid.
43) S. Ohta: "Why are Finite-Temperature
QCD Phase Transitions So Weak?",
RCNP Workshop, Osaka, June (1992).
44) E.A.G. Armour, D.M. Lewis, and S.
Hara: "Calculation of the Auger Deexcitation Rate of the dtji 'Nucleus' of the
Muonic Quasi- Molecule [(dtji) deeJ",
Int . Workshop on Muon Catalyzed
Fusion (jiCF -92), Uppsala, Sweden,
June (1992) .
45) T . Motobayashi: "The 13N (p, y) 140
Reaction from Coulomb Dissociation",180th Meet. of Am . Astron. Soc.,
Columbus, U.S.A., June (1992).
46) H. T. Duong, C. Ekstrom, M. Gustafsson, T . T . Inamura, P . J uncar , P .
Leivens, I. Lindgren, S. Matsuki, T.
Murayama, R. Neugart, T. Nilsson,
T. Nomura, M. Pellarin, S. Penselin,
J. Persson, J . Pinard, I. Ragnarsson,
O. Redi, H.H. Stroke, and J .L. Vialle:"Atomic Beam Magnetic ResonanceApparatus for Systematic Study ofBohr - Weisskopf effect at BoosterIsolde", 6th Int. Conf. on Nuclei farfrom Stability, Bernkastel- Kues, Germany, July (1992).
47) C.-B. Moon, M. Fujimaki, N. Inabe,
K . Katori, J .C. Kim, T . Kobayashi,
T. Kubo, H. Kumagai, S. Shimoura,
T. Suzuki, a~d I. Tanihata: "Measurements of Angular Distributions for thellLi +p and 9Li +p Elastic Scatterings",
ibid.
48) I. Tanihata, D. Hirata, T . Kobayashi,

and H. Toki: "Disclosure of Thick
Neutron Skins", ibid.
49) I. Tanihata, D. Hirata, T. I\obayashi,
S. Shimoura, K. Sugimoto and H.
Toki: "Revealing of Thick Neutron
Skins in Nuclei", ibid.
50) S. Shimoura, T. Nakamura, M. Ishihara, N. Inabe, T. Kobayashi, T.
Kubo, R.H. Siemssen, I. Tanihata,
and Y. Watanabe: "EI Strength Distribution of llLi by Invariant Mass
Spectroscopy", 6th Int. Conf. on Nuclei
far from Stability and 9th Int. Conf. on
Atomic Masses and Fundamental Constants, Berenkastel-Kues , Germany,
July (1992).
51) J. Chiba, D. Aschery, H. Ito, K.
Kimura, Yu T. Kiselev, S. Koda, K.
Miyano, T. Murakami, T. N agae, Y.
Nakai, M. Nomachi, S. Sawada, M.
Sekimoto, T. Suzuki, K. H. Tanaka,
M. K. Vlasov, and Y. Yoshimura: "Enhancement of Subthreshold Antiproton
Production in Deuteron Induced Reactions" , Int. Nuclear Physics Conf.,
Wiesbaden, Germany, July (1992).
52) I. Tanihata: "Radioactive Beam Facilities and Their Physics Program", ibid.
53) T. Kobayashi: "Nuclear Structure
Experiments with llLi", ibid.
54) S. Date: "Ultrarelativistic AA Collision
Simulator Based on Multichain Algorithm", XXII Int. Symp. on Multiparticle Dynamics, Santiago de Compostela ,Spain, July (1992).
55) M. Fujii et at.: "Performance ofMedium Energy Isotope Telescope for
Geotail High Energy Particle Experiment", Chu-Shikoku Section Meeting
Phys. Soc. Jpn., Ehime, July (1992).
56) W.G. Jin, M. Wakasugi, T. Inamura,T. Murayama, T. Wakui, T. Kashiwabara, H. Katsuragawa, T. Ariga, T.
Ishizuka, M. Koizumi, and I. Sugai:"Isotope Shift and Hyperfine Structureof Refractory Elements by Laser
Spectroscopy with Sputtered Atomic
Beams", RIKEN Int. Symp. on Unstable Nuclei and Particles as Probes inPhysics and Chemistry, Wako, Aug.
(1992) .
57) I. Tanihata: "Neutron Halo in Nuclei",ibid.
58) I. Tanihata: "Unstable Nuclear Beams
for Study of Nuclei far from Stability",
5th Asia Pacific Physics Conf., Kuala-202-

Lumpur, Malaysia, Aug. (1992).
59) H. Okuno: "Polarization in Projectile
Fragmentation and g-Factor Measurements for Neutron-Rich Nuclei", IXthInt. Conf. on Hyperfine Interactions,
Osaka, Aug. (1992).
60) K. N aga ta, T. Kashi wagi, J. Kikuchi,
T. Doke, K. Itsumi, T. Shino, N.
Hasebe, H. Moriya, A. Nakamoto, T.
Yanagimachi, H. Murakami, S.
Sugino, and T. Kohno: "Energy Lossand its Straggling of High Energy
Heavy Ions in Silicon Detector", 1992
Fall Meet. Phys. Soc. Jpn., Tokyo,
Sept. (1992).
61) C. Kato, T. Imai, A. Yoneda, K.
Munakata and T. Kohno: "On a Probability of Nuclear Fragmentation in Cosmic Ray Silicon Detector Telescope",
ibid., Niigata, Sept. (1992).
62) Y. Gono, S. Mitarai, A. Odahara, E.
Ideguchi, T. Shizuma, N. Kidera, T.
Morikawa, Y. H. Zhang, A. Ferragut,
K. Morita, A. Yoshida, K. Murakami,
M. Ogawa, M. Nakajima, M. Oshima,
H. Kusakari, M. Sugawara, B. J .
Min, J .C. Kim, and S.J. Chae: "HighSpin Isomer of 145Sm", ibid., Oct. (1992).
63) K. Tanaka and W. Bentz: "Equation ofState for Nuclear Matter including
Higher Orders in a Relativistic ManyBody Theory", ibid.
64) N. Ishida, T. Doke, K. Kuwahara, M.
Ichige, S. Ben, M. Suzuki, A. Hitachi,
K. Masuda: "Efficiency of Light Collection in Liquid Xenon", ibid.
65) T. Wakui, T. Ariga, T. Ishizuka, T.
Inamura, T. Kashiwabara, H. Katsuragawa, W.G. Jin, M. Koizumi, T.
Shinozuka, K. Shimomura, I. Sugai,
M. Takami, Y. Tagishi, I. Nakamura,T. Horiguchi, S. Matsuki, T. Murayama, K. Morita, Y. Yano, A. Yoshida, and M. Wakasugi: "Collinear Laser
Spectroscopy with Laser - Ablation
IGISOL", ibid.
66) K. Sumiyoshi, D. Hirata, H. Toki, H.
Sagawa: "Comparison of the Relativistic Mean Field Approach with theSkyrme Interaction for Infinite Matterand Nuclei", ibid.
67) D. Hirata, 1. Tanihata, H. Toki, P.
Ring: "Relativistic Mean Field Theory
for Deformed Nuclei", ibid.
68) S. Yamaji, A.S. Jensen, and H. Hofmann: "Isoscalar Vibrational States inKubo, T. Nakagawa, Y. Watanabe,
S. Shimoura, and T. Tanihata: "Search
for a Pineut", ibid.
69) K. Soutome, S. Yamaji, and M. Sano:"Nuclear Dissociation Cross Sections ofllLi", ibid.
70) S. Hirenzaki and H. Toki: "Formationof Deeply Bound Pionic Atoms by (d,3He) Reactions", ibid.
71) N. Sakamoto: "The Construction of
RIKEN Polarized Ion Source", ibid.
72) M. Tohyama: "Comparison between
TDDM and VUU", ibid.
73) H. Suganuma: "Chiral Solitons without
Nonlinear Constraint and Chiral Bag
Picture", ibid.
74) H. Ueno: "Measurement of 21F Nuclear
Moment Using Spin-Polarization in
Fragmentation Reaction", ibid.
75) S. Yamaji, A.S. Jensen, and H. Hofmann: "Isoscalar Vibrational States in
Hot Nuclei", 1st INFN-RIKEN Joint
Meet. on Perspective in Heavy Ion
Physics, Catania, Italy, Sept. (1992).
76) Y. Gono, T. Morikawa, T. Murakami, A. Ferragut, Y.H. Zhang, K.
Morita, A. Yoshida, M. Oshima, H.
Kusakari, M. Sugawara, M. Ogawa,
M. Nakajima, J .C. Kim, S.J. Chae,
B.J. Min, S. Mitarai, A. Odahara, E.
Ideguchi, T. Shizuma, and N. Kidera:"Physics on/with Extremely High-Spin
Isomers", ibid.
77) T. Nakagawa, K. Yuasa-Nakagawa,
S.C. Jeong, H. Fujiwara, Y.H. Pu,
Y. Futami, B. Heusch, K. Ieki, T.
Sugimitsu, T. Matsuse, and S.M. Lee:
"Complex Fragment Emission from the
Hot Compound Nucleus", ibid.
78) S. Shimoura:"Invariant Mass Spectroscopy on Excitation Modes of Neutron
Drip Line Nuclei", ibid.
79) S. Ohta: "Lattice QCD Numerical Calculations on AP1000", Int. Conf. on
Computing in High Energy Physics '92,
Annecy, France, Sept.' (1992).
80) S. Ohta: "Large Scale Numerical Simulation of the Three-State Potts Model" ,Int. Conf. on "Lattice '92," Amsterdam, the Netherlands, Sept. (1992).
81) T. Doke, J. Kikuchi, T. Hayashi, T.
Kashiwagi, K. Itsumi, T. Shino, T.
Ito, N. Hasebe, H. Moriya, K. Fujiki,
A. Nakamoto, H. Murakami, T.
Yanagimachi, S. Sugino, K. Nagata,and T. Kohno: "Identification of Iso--203-

topes by Telescope HEP- MI aboard the
Geotail Satellite Using RIKEN Ring
Cyclotron Accelerator", ibid.
82) Y. Gono, T. Morikawa, T. Murakami, A. Ferragut, Y.H. Zhang, K.
Morita, A. Yoshida, M. Oshima, H.
Kusakari, M. Sugawara, M. Ogawa,
M. Nakajima, J .C. Kim, S.J. Chae,
B.J. Min, S. Mitarai, A. Odahara, E.
Ideguclii, T. Shizuma, and N. Kidera:"High-Spin Isomers and High-Spin
Isomer Beams", 21st INS Int. Symp. on
Rapidly Rotating Nuclei 92, Tokyo,
Oct. (1992).
83) M. Oshima, H. Kusakari, M. Sugawara, Y. Gono, A. Ferragut, Y.H.
Zhang, S. Ichikawa, and T. Inamura:"Double-y Vibrational State in 168Er",
ibid.
84) S. Yamaji, H. Hofmann, and A.S.
Jensen: "Distribution of Strength for
Isoscalar Modes at Finite Temperature", ibid.
85) Y. Gono, T. Morikawa, T. Murakami, A. F erragut, Y. H. Zhang, K.
Morita, A. Yoshida, M. Oshima, H.
Kusakari, M. Sugawara, M. Ogawa,
M. Nakajima, J .C. Kim, S.J. Chae,
B.J. Min, S. Mitarai, A. Odahara, E.
Ideguchi, T. Shizuma, and N. Kidera:"High-Spin Isomers and High - Spin
Isomer Beams", 6th Franco-Japanese
Colloquim on Nuclear Structure andInterdisciplinary Topics, Saint-Malo,
France, Oct. (1992).
86) T. Motobayashi: "Coulomb Excitationof Unstable Nuclei: Application to
Nuclear Astrophysics and Nuclear
Spectroscopy" , ibid.
87) K. Yazaki: "Quark Degress of Freedom
in Nuclei", ibid.
88) T. Motobayashi: "Coulomb Breakup
Measurements for Determination of
Astrophysical (p, y) Reaction Rates",Ann. Fall Meet. Div. Nucl. Phys., Am.
Phys. Soc., Santa Fe, U.S.A., Oct.
(1992) .
89) H. Toki and Y. Sugahara: "Relativistic
Equation of State with Strangeness for
Neutron Stars", Int. Symp. on Origin
and Evolution of the Elements, INS,Tokyo, Oct. (1992) .
90) T. Kobayashi: "Momentum Distributionof Projectile Fragments from N eutronRich Nuclei", INFN-RIKEN Symp. on
Intermediate-Energy Nuclear Physics,

Catania, Italy, Oct. (1992).
91) Y. Gono, T. Morikawa, T. Murakami, A. Ferragut, Y.H. Zhang, K.
Morita, A. Yoshida, M. Oshima, H.
Kusakari, M. Sugawara, M. Ogawa,
M. Nakajima, J .C. Kim, S.J. Chae,
B.J. Min, S. Mitarai, A. Odahara, E.
Ideguchi, T. Shizuma, and N. Kidera:"High-Spin Isomer Beams", RIKEN
Symp. on Nuclear Spectroscopy with
Unstable Nuclear Beams, Wako, Nov.
(1992) .
92) Y. Gono: "High Spin Isomer Beams",
ibid.
93) 1. Tanihata: "Study of Neutron-Drigline Nuclei Using Radioactive Nuclear
Beams", 12th Int. Conf. on the Application of Accelerators in Research &Industry, Denton, U.S.A., Nov. (1992).
94) T. Ichihara: " 12 C (12C, 12N) 12B Charge-Exchange Reaction at E/ A=135MeV",
Japan-China Joint Symp., Tokyo, Nov.
(1992) .

3. Atomic and solid-state physics
1) K. Kuroki, Y. Yamazaki, K. Komaki,
T. Azuma, N. Kakutani, K. Kawatsura, Y. Kanai, T. Kambara, and Y.
Awaya: "Observation of Relativistic
Electrons in Relativistic Heavy-IonAtom Collisions", Int. Conf. Atomic
Collisions in Solids, Salford, U. K., July
(1991) .
2) K. Aono, M. Iwaki, Y. Aoyagi, and
S. N amba: "Tb-ion Implantation into
CaF 2 III", 52nd Autumn Meet. J pn.
Soc. Appl. Phys., Okayama, Oct.
(1991) .
3) K. Ando: "The Present State of X-Ray
Laser", RIKEN Symp. on Studies ofSolid State Physics and Materials,
Atomic Processes, Nuclear Chemistry,
and Biology and Medical Science byUsing RIKEN Ring Cyclotron, Wako,
Jan. (1992).
4) R. Kadono: "Anomalous Muonium Centers and Relaxed Excitonic States", ibid.
5) I. Shimamura: "Positron-Atom andPositron - Molecule Collisions", ISSP
Symp. on Solid State Physics by Monochromatic Slow Positron - Beam,Tokyo, Jan. (1992).
6) T. Kambara: "Atomic Collision Experiments at Heidelberg TSR" , Meet.
Atomic Physics with Cooler Ring,
Tanashi, Feb. (1992).

-204-7) Y. Matsuo, H. Maeda, and M. Takami: "Spectroscopy and Dynamics of
Heavy Metallic Ions in an RF Trap",
RIKEN Symp. on 14th Laser Science,
Wako, Feb. (1992).
8) H. Fukuda and I. Shimamura: "AO-MO
Matching for j.l - Transfer Reactions",
47th Ann. Meet. Phys. Soc. Jpn., Yokohama, Mar. (1992).
9) I. Shimamura: "Moleculelike Description of Metastable, Highly Excited Antiprotonic Helium", ibid.
10) T. Kambara: "Atomic Physics Experiments at RIKEN", ibid.
11) T. Nabeshima, N. Nakamura, Y.
Kanai, S. Ohtani, S. Kitazawa, M.
Nagata, T. Takayanagi, K. Wakiya,
H. Suzuki, T. Kambara, and Y.
Awaya: "Ejected Electron Spectra from
Triplet States of 04+ Cls 2nln'I')
Produced by 0 6 + + O2 Collision", ibid.
12) Y. Zou, Y. Awaya, T. Kambara, Y.
Kanai, M. Ohura, K. Ando, A. Hitachi, and S.D. Kravis: "Foil Target
Element and Incident Energy Dependence of Multiple Inner-shell Vacancy
Production of Projectile Ar Ions", ibid.
13) Y. Yamazaki, K. Komaki, T. Azuma,
K. Kuroki, K. Kawatsura, Y. Kanai,
T. Kambara, M. Ohura, and Y.
Awaya: "High Energy Electron Production in Relativistic Heavy Ion Atom
Collision II", ibid.
14) K. Ando, Y. Zou, Y. Awaya, T.
Kambara, M. Ohura, T. Tonuma, and
S. Tsurubuchi: "Lifetimes of N e-Like
Cr Ion Measured by Beamfoil Spectroscopy", ibid.
15) J. Mitani, I. Hashimoto, H. Yamaguchi, E. Vagi, and M. Iwaki: "Annealing Effect on Kr Bubbles in Kr-Implanted Aluminium", ibid.
16) E. Vagi: "Kr Bubbles in Aluminium",
ibid.
17) S. Sakamoto, K. Ishida, T. Matsuzaki, K. N agamine, P. Strasser, andY. Watanabe: "Muon Transfer Reactions in Liquid Deuterium with Helium
Impurity III", ibid.
18) Y. Matsuo, H. Maeda, and M. Takami: "RF Trap of Heavy Metallic Ions
from Laser-Produced-Plasma II", ibid.
19) K. Ando, Y. Zou, Y. Awaya, T.
Kambara, M. Oura, T. Tonuma, and
S. Tsurubuchi: "Lifetimes of N e-like Cr
Ion Measured by Beam-Foil Spectros-copy", ibid.
20) R. Kadono, A. Matsushita, K. Nishiyama, and K. Nagamine: "Muonium
Fluorescence: Anomalous Muonium
Centers and Relaxed Excited States in
KBr", ibid.
21) Y. Awaya and M. Kimura: "Researchand Development for Experiments at
SPring -8" , SPring -8 Workshop on
Atom. Phys. at High Brilliance
Synchrotron Radiation Facilities (11thRIKEN Symp.), Himeji, Mar. (1992).
22) S.D. Kravis: "Atomic Physics Experiments with an EBIS and Synchrotron
Radiation", ibid.
23) K. Aono, M. Kumagai, M. lwaki, and
Y . Aoyagi: "Tb-ion Implantation into
CaF 2 IV", 39th Spring Meet. , J pn. Soc.
Appl. Phys. Related Soc., N arashino,Mar. (1992).
24) E. Yagi: "Behaviour of Kr Atoms Implanted into Aluminium", RIKEN
Symp. on Relation between Ion Beams
and Surface Layer and Interface,
Wako, Mar. (1992).
25) T. Kambara, Y. Awaya, Y. Kanai,and A. Hitachi: "Multiple Inner- Shell
Ionization of Target Atoms by HighEnergy Heavy- Ion Impact", 2nd Int.
Symp. on Swift Heavy Ions in Matter,
Bensheim, Germany, May (1992).
26) Y. Zou, Y. Awaya, T. Kambara, Y.
Kanai, M. Oura, K. 'Ando, A. Hitachi, and S. Kravis: "Foil Target Element and Incident Energy Dependenceof Multiple Inner-Shell Vacancy Production of Projectile Ar Ions", ibid.
27) Y. Yamazaki, K. Kuroki, H. Knudsen, K. Komaki, T. Azuma, K.
Kawatsura, Y. Kanai, T. Kambara,
M. Oura, and Y. Awaya: "Relativistic
Electron Emission in Ion- Atom Collisions", ibid.
28) R. Kadono: "Muon Diffusion in Dis-.
sipative Systems", Int. Symp. on
Metal-Hydrogen Systems, Fundamentals and Applications, Uppsala,Sweden, June (1992).
29) M.R. Harston, 1. Shimamura, and M.
Kamimura: "Energy Shift in the dt,u dee
Molecular Hybrid due to the Finite Sizeof the Muonic Molecular Ion dt,u", Int.
Workshop on Muon Catalyzed Fusion(,uCF - 92), Uppsala, Sweden, June
(1992) .
30) K. Ishida, T. Matsuzaki, Y.

-205-

Watanabe, S. Sakamoto, K.
Nagamine, and P. Strasser: "X-ray
Studies of Muon Transfer Reactions
from Hydrogen to Helium", ibid.
31) P. Strasser, K. Ishida, S. Sakamoto,
M. Iwasaki, E. Torikai, K.
Nagamine, and G.M. Marshall:"Towards Slow ,u - Production via
Muon Catalyzed Fusion", ibid.
32) K. Nagamine: "X - Ray Studies ofMuon-alpha Sticking and Muon Transfer in Muon Catalyzed Fusion", ibid.
33) K. Nagamine: "Slow and Monoenergetic (3He,u - ) Beam Production andNovel Applications", ibid.
34) K. Nagamine: "Future ,uCF Programwith Pulsed Muons at RIKEN-RAL andat UTMSL-KEK", ibid.
35) M. Oura, T. Kambara, Y. Kanai, S.
Kravis, Y. Zou, J. Palinkas, and Y.
Awaya: "Study of Radiative Electron
Rearrangement (RER) Processes", 17th
Meet. Soc. for Atomic Colli. Res.,
Wako, Aug. (1992).
36) Y. Zou, Y. Awaya, T. Kambara, Y.
Kanai, M. Our a , K. Ando, Y. Nakai,
A. Hitachi, and S. Kravis: "Study ofInner-Shell Vacancy Production of Ar
Projectile in Collision with Foil Target", ibid.
37) S. Kravis, K. Okuno, H. Saitoh, K.
Soejima, Y. Kaneko, M. Our a , and Y.
Awaya: "New Results for Single andDouble Charge Transfer Cross Sections
in ArQ+ + H2 Collisions at Low Energies
for 6=::;:q=::;:8", ibid.
38) A. Matsushita, R. Kadono, K. Nishiyama, Y. Miyake, A. Nakao, J. Takahashi, M. Iwaki, and K. N agamine:"Muonium Emission and Reaction on
the Platinum and Gold Powder Surfaces
Revealed by MuSR", 9th Int. Conf.
Hyperfine Interactions, Toyonaka,
Aug. (1992).
39) R. Kadono, A. Matsushita, K. Nishiyama, and K. N agamine: "Relaxed
Excited States and Anomalous Hyperfine Structure of Muonium Centers in
KBr", ibid.
40) T. Okada , K. Asai, N. Yamada, Y.
Yamada, T. Matsumoto, and Y.
Kodama: "57Fe Mossbauer Studies of
YBaz (Cul-xFex) 4 Os", 3rd Int. Symp. on
the Industrial Applications of the Mossbauer Effect, Otsu, Aug. (1992).
41) E. Yagi: "Channelling Study on theLattice Location of Hydrogen in Metals
by a Nuclear Reaction-Channelling
Method", RIKEN Int. Symp. on Unstable NuClei and Particles as Probes inPhys. and Chern., Wako, Aug. (1992).
42) T. Okada, K. Asai, N. Yamada, T.
Matsumoto, · Y. Yamada, and Y.
Kodama: " 57 Fe Mossbauer Fraction of
YBa2 (Cul -xFex) 408 ", ibid., Sept. (1992).
43) Y. Kanai: "Doubly - Excited States of
He - Like and Be - Like Ions in Highly
Charged Ions", 6th Int. Conf. on the
Physics of Highly Charged Ions, Manhattan, U. S. A., Sept. (1992).
44) Y. Kanai, T. Kambara, M. Oura, Y.
Zou, S. Kravis, and Y. Awaya: "Binary
Encounter Peaks for 0° Electrons in
Collisions of O. 8MeV I amu Bi q + with H2and He", ibid.
45) M. Oura, T. Kambara, Y. Kanai, S.
Kravis, Y. Zou, J. Palinkas, and Y.
A waya: "Measurement of RER X Rays
from 0.8MeV lu Ar Ions Passing
through Target Foil", ibid.
46) S. Kravis, K. Okuno, H. Saitoh, K.
Soejima, Y. Kaneko, M. Our a , and Y.
Awaya: "Single and Double Charge
Exchange Cross Sections for Ar q + + H2
(q=6, 7, and 8) from 8eV to 8keV",ibid.
47) S. Kravis, K. Okuno, T. Kojima, M.
Kimura, S. Ohtani, T. Kambara, Y.
Kanai, and Y. Awaya: "An EBIS for
Use with Synchrotron Radiation(Photoionization of Highly ChargedIons) ", ibid.
48) N. Nakamura, T. Negishi, Y. Kanai,
S. Ohtani, S. Kitazawa, M. Nagata,
T. Takayanagi, K. Wakiya, H. Suzuki, T. Kambara, and Y. A waya:"Ejected Electron Spectra from Quartet
States of N4+* * (ls3131') Produced by
N6+ + O2 Collisions", 1992 Fall Meet.
Phys. Soc. Jpn., Tokyo, Sept. (1992).
49) T. Yoshida and I. Shimamura: "Highly
Excited States of Antiprotonic Neon",
ibid.
50) I. Shimamura: "Scaling of the Cross
Sections for Molecular Vibrational
Transitions by Electron Impact", ibid.
51) Y. Matsuo, H. Maeda, and M. Takami: "Heavy Metallic Ions in an RF Trap:
Reaction with Molecules and Spectroscopy", ibid.
52) T. Okada, K. Asai, N. Yamada, T.
Matsumoto, Y. Yamada, and Y.

-206-

Kodama: "Mossbauer Fraction of YBa2
(Cul-xFex) 40 8 ", ibid.
53) E. Yagi and S. Koike: "Lattice Location of Hydrogen in Nb - Mo Alloys",ibid.
54) M. Takami and Y. Matsuo: "Spectroscopy and Chemical Reactions of Heavy
Metallic Ions in an RF Trap", 1992
Symp. on Molecular Science, Kyoto,
Sept. (1992).
55) K. Aono, M. Kumagai, M. Iwaki, Y.
Aoyagi, and S. N amba: "Radiation
Damage in Tb- implanted CaF 2 Observed by the Channeling Method andLuminescence IBMM '92", Heidelberg,
Germany, Sept. (1992).
56) E. Yagi: "Solid Krypton Precipitates in
Kr-Implanted Aluminium", Int. Conf.
on Diffusion in Mater., Kyoto, Sept.
(1992) .
57) R. Kadono: "Muon Diffusion in Solids" ,ibid.
58) I. Shimamura: "The Theory of Extraordinarily Long - lived Antiprotonic
Helium" , Symp. on the Dynamic
Processes Involving Exotic Atoms,
Wako, Sept. (1992).
59) Y. Yamazaki, K. Komaki, M. Sataka, M. Imai, Y. Kanai, K. Kawatsura,
H. Tawara, and D. R. Schultz: "Electron Emission in Energetic Heavy IonAtom Collisions", 4th China-Japan
Seminar and 1st East Asian Int. Seminar on Atomic and Molecular Physics,
Tokyo, Oct. (1992).
60) Y. Awaya, T. Kambara, and Y.
Kanai: "Multiple Inner-Shell Ionizationin Heavy Ion-Atom Collisions", ibid.
61) I. Shimamura: "Moleculelike Metastable States of Antiprotonic Helium", ibid.
62) H. Shibata, T. Tonuma, T. Matsuo,
H. Kumagai, and H. Tawara: "Multiply Charged Ions from Gaseous andFrozen SF 6 and CF 4 Produced by Energetic Heavy Ion Impact", 6th Int. Conf.
on the Physics of Highly Charged Ions,
Kansas, U.S.A., Oct. (1992).
63) H. Tawara, T. Tonuma, H.
Kumagai, and T. Matsuo: "Multiple
Ionization: Comparison between Gas
and Condensed Matter", Joint Int. Seminar on Atomic and Molecular Physics,
Tokyo, Oct. (1992).

4. Radiochemistry, radiation chemistry, andradiation biology

1) J. Kurachi, E. Taniguchi, A. Shinohara, ' M. Furukawa, S. Kojima, Y.
Ohkubo, F. Ambe, K. Takesako, T.
Saito, and S. Shibata: "Nuclear Reaction Products in the Interaction of 197Au
with Intermediate Energy Heavy Ions" ,63rd Natl. Meet. Chern. Soc. Jpn.
(Spring), Osaka, Mar. (1992).
2) K. Takesako, T. Saito, H. Kusawake,
S. Watanabe, K. Goto, A. Yokoyama,
H. Baba, Y. Ohkubo, A. Shinohara,
and M. Furukawa: "Target Fragmentation of 141Pr and 165Ho Induced by 14N,
15N, and 40 Ar Projectiles", ibid.
3) J. Kurachi, E. Taniguchi, A. Shinohara, M. Furukawa, S. Kojima, Y.
Ohkubo, F. Ambe, K. Takesako, T.
Saito, and S. Shibata: "Nuclear Reaction Products in the Interactions of 197Au
with Intermediate Energy Heavy Ions" ,ibid.
4) N. Ohmori, A. Kimura, A. Ejiri, K.
Kimura, and K. Nakagawa: "Electronion Recombination in Photoionization of
Anthracene Doped in Non-polar Solvents", Spring Meet. Phys. Soc. J pn.,
Hiyoshi, Mar. (1992).
5) K. Nakagawa, A. Ejiri, K. Kimura,
K. Tanaka, A. Kimura, N. Ohmori,and D. Nurdiawati: "Origin of Structureof Photo current Spectrum of Anthracene Doped in N on-Polar Solvents",
ibid.
6) K. Ando, S. Koike, C.K. Cho, and T.
Kanai: "Mouse Skin Damage after Carbon Irradiation", 31st Ann. Meet. Radiation Biology Division of Jpn. Radiol.
Soc., Yokohama, Apr. (1992).
7) S. Koike, K. Ando, T. Kanai, and M.
Kimoto: "Therapeutic Effectiveness ofCarbon Spread-Out-Bragg-Peak", ibid.
8) K. Kimura: "Track - depth Resolved
Dynamics of Helium Excimers in 4
MeV /amu N-ion Tracks in Near- Liquid and Liquid Helium", Int. Conf.
Liquid Radiat. Detector, Tokyo, Apr.
(1992) .
9) K. Kimura: "Lifetime Shortening and
Quenching of the Excitons of a BaF 2
Single Crystal Created by Heavy-Ion
Induced High Density Excitation", 2ndInt. Symp. on Swift Heavy Ions in
Matt., Bensheim, Germany, May (1992).
10) K. Ki~ura: "Excited State Dynamics-207-

Resolved along the Depth of Ion Tracks. in Dense Rare Gases", ibid.
11) S. Ambe, Y. Ohkubo, M. Iwamoto, Y.
Kobayashi, and F. Ambe: "Preparationof Radioactive Multitracer Solutions
from a High - Energy Heavy - Ion
Irradiated Au Target by Means of a
Supported Liquid Membrane" , 53rd
Symp. on Anal. Chern., Akita, May(1992) .
12) F. Yatagai, S. Hachiya, Y. Hama, A.
J.E. Gordon, M. Izumi, H. Miyazawa, S. Harakawa, and F. Hanaoka:"Resolution and Characterization ofPolymorphic DNA by SSCP and Chemical Cleavage Methodologies", Gordon
Res. Conf. (Mutagenesis), Plymouth,
U.S.A., June (1992).
13) K. Ando and H. Tatsuzaki: "Volume
Effect: from a Radio -biological Point ofView", 22nd Symp. on Cancer Control,
Sapporo, June (1992).
14) K. Kimura: "Lifetime Shortening and
Quenching of the Excitons of a BaF 2
Single Crystal Created by Heavy- Ion
Induced High Density Excitation", Gordon Conf., Newport, U.S.A., July
(1992) .
15) K. Kimura: "Excited State Dynamics
Resolved along the Depth of Ion Tracks
in Dense Rare Gases", ibid.
16) T. Takahashi, M. Suzuki, F. Yatagai,
and K. Izumo: "Calculation and a Preliminary Experiment on the Energy
Deposition around the Path of an Ion",
29th Ann. Meet. Radioisotopes in the
Physical Sciences and Industries,
Tokyo, July (1992).
17) S. Ambe, Y. Ohkubo, M. Iwamoto, Y.
Kobayashi, M. Yanokura, and F.
Ambe: "Preparation of Multitracers andTheir Application to a Study on Plant" ,ibid.
18) K. Nakagawa, A. Ejiri, K. Kimura,
K. Tanaka, D. Nurdiawati, N. Ohmori,and A. Kimura: "Density Dependence ofStructures in Photocurrent and Optical
Absorption Spectra of Anthracene
Doped in Supercritical Xenon Fluids",
10th Int. Conf. VUV Radiat. Phys.,
Paris, France, July (1992).
19) Y. Itoh, H. Murakami, and A. Kinoshita: "Positron Annihilation Study on
Nanometer Cavities in Porous Silicon",
RIKEN Int. Symp. on Unstable Nuclei
and Particles as Probes in Physics andChemistry, Wako, Aug. (1992).
20) Y. Itoh and H. Murakami: "Recovery
and Clustering of Defects in GaAs Studied by Means of Positron Annihilation" ,ibid.
21) Y. Ohkubo, Y. Kobayashi, K. Harasawa, S. Ambe, T. Okada, K. Asai,
S. Shibata, M. Takeda, and F. Ambe:"Time-Differential y- Ray PerturbedAngular - Correlation (TDPAC) andEmission Mossbauer Spectroscopy of
99Ru in YBa2Cu307-X Using 99Rh as a
Source Nuclide", ibid.
22) H. Ueno, H. Okuno, K. Asahi, H.
Sato, M. Adachi, T. Kubo, T. Nakamura, N. Inabe, A. Yoshida, Y. Ohkubo, T. Ichihara, M. Ishihara, T.
Shimoda, H. Miyatake, N. Takahashi, and W. -D. Schmidt-Ott: "SpinPolarized Radioactive Beams and /3NMR Experiments", ibid .
23) Y. Kobayashi, K. Asai, T. Okada,and F. Ambe: "Mossbauer and Magnetization Studies on Ferromagnet Fe3-X
RUxSi", ibid.
24) K. Ando, K. Koike, K. Fukutsu, M.
Kimoto, M. Iizuka , T. Kiuchi, T.
Aruga, W. Shimizu, T. Sugita, C. K.
Cho, T. Kanai, S. Furukawa, H.
Kato, S. Matsushita, Y. Furusawa,and F. Yatagai: "Effects of Accelerated
Carbon Ions on Normal Tissues andTumors in Experimental Animals", 2ndWorkshop of Heavy Ion Research,
Chiba, Aug. (1992).
25) Y. Ohkubo, Y. Kobayashi, K. Asai,
T. Okada, and F. Ambe: "TDPAC andEmission Mossbauer Studies of Fe 304(99Ru) ",9th Int. Conf. on Hyperfine
Interact., Toyonaka, Aug. (1992).
26) K. Ogura, M. Matusima, Y. Yamada,T. Takahashi, F. Yatagai, H. Ohnishi, T. Kasuya, T. Doke, K. Kuwahara, and S. Nagaoka: "Determinationof High LET Cosmic Particles, Trajectories for Space RadiobiologicalStudies", 16th Int. Conf. on Nuclear
Tracks in Solids, Beijin, China, Sept.
(1992) .
27) K. Ogura, T. Naito, K. Nakano, andT. Takahashi: "Application of the PreSoaking Effects to the Production of
CR-39 Microfilters", ibid.
28) K. Kimura, K. Morita, R. Nemoto,and S. Nakamura: "Depth-resolved
Dynamics of VUV Luminescence in Ion-208-

Tracks in Dense Helium Gase" , 1992
Fall Meet. Phys. Soc. lpn., Tokyo,
Sept. (1992)
29) K. Kimura, K. Morita, R. Nemoto, S.
Nakamura, and H. Kumagai: "Mechanism of Lifetime Shortening of Augerfree Luminescence from Ion- Irradiated
BaF2", ibid.
30) Y. Ohkubo, Y. Kobayashi, K. Asai,
T. Okada, and F. Ambe: "TDP AC andEmission Mossbauer Studies of Fe30 4(99Ru) ", ibid.
31) Y. Itoh, H. Murakami, and A. Kinoshita: "Positron Annihilation Study on
Nanometer Cabities in Porous Silicon",
53th Fall Meet. Jpn. Soc. Appl. Phys.,
Osaka, Sept. (1992).
32) Y. Ohkubo, Y. Kobayashi, S. Ambe,
T. Okada, F. Ambe, K. Harasawa,
M. Takeda, K. Asai, and S. Shibata:"TDP AC and Emission Mossbauer
Studies on 99Ru Arising from 99Rh in
YBa 2Cu 307-X", 36th Symp. on Radiochemistry, Hachioji, Oct. (1992).
33) M. Iwamoto, S. Ambe, Y. Ohkubo, Y.
Kobayashi, M. Yanokura, H. Maeda,
and F. Ambe: "Separation ofMultitracer by Heating under Reduced
Pressure", ibid.
34) S. Ambe, Y. Ohkubo, M. Iwamoto, Y.
Kobayashi, M. Yanokura, H. Maeda,
F. Ambe, S. Shibata, T. Yaita, F.
Bamba, H. Harakawa, H. Saito, andK. Kimura: "Study on the Ion Exchange
Adsorption of Various Elements on
Superacid Resin N AFION U sing a
Multitracer", ibid.
35) Y. Minai, Y. Takahashi, M. K. Kubo,
S. Toyoda, M. Ishibashi, S. Ambe, Y.
Kobayashi, Y. Ohkubo, M. Iwamoto,
M. Yanokura, H. Maeda, S. Shibata,N. Takematsu, F. Ambe, and T.
Tominaga: "Multitracer Study on Complex Formation of Humic Acid", ibid.
36) S. Ambe, S. Tanaka, Y. Kobayashi,
Y. Ohkubo, M. Iwamoto, H. Maeda,
M. Yanokura, and F. Ambe: "Study of
Selective Transport of Metal- Ions by
Means of a Supported Liquid Membrane
Using a Multitracer (1)", ibid.
37) S. Tanaka, S. Ambe, Y. Kobayashi,
Y. Ohkubo, M. Iwamoto, H. Maeda,
M. Yanokura, and F. Ambe: "Study of
Selective Transport of Metal-Ions by
Means of a Supported Liquid Membrane
Using a Multitracer (II)", ibid.

38) S. Shibata, K. Watari, Y. Noda, S.
Ambe, Y. Ohkubo, M. Iwamoto, Y.
Kobayashi, M. Yanokura, H. Maeda,
and F. Ambe: "Study on the Adsorption
Behavior of Various Elements in Chloride Solutions on a MR Type Resin andan Activated Carbon Fiber Using a
Multitracer", ibid.
39) S. Watanabe, K. Takesako, T. Saito,
H. Baba, Y. Ohkubo, A. Shinohara,
E. Taniguchi, and M. Furukawa:"Symmetric Mass Division in the IrComposite System", ibid.
40) M. Kiriu, T. Saito, A. Yokoyama, H.
Baba, E. Taniguchi, and Y. Ohkubo:"Investigation of the 7MeV /nucleon 58
Ni-Induced Reaction on Cu and Rh
Targets", ibid.
41) J. Kurachi, E. Taniguchi, A. Shinohara, M. Furukawa, S. Kojima, Y.
Ohkubo, F. Ambe, K. Takesako, T.
Saito, and S. Shibata: "Nuclear Reaction Products in the Interactions of 197Au
and Intermediate Energy Heavy Ions
14N, 15N, and 4°Ar", ibid.
42) E. Taniguchi, J. Kurachi, A. Shinohara, M. Furukawa, S. Kojima, Y.
Ohkubo, F. Ambe, K. Takesako, T.
Saito, and S. Shibata: "Nuclear Reactions with Intermediate Energy Heavy
Ions on V, Cu, Nb, and I-The Dependence on Projectiles and Targets-", ibid.
43) K. Takesako, T. Saito, H. Kusawake, A. Yokoyama, H. Bamba, Y.
Ohkubo, A. Shinohara, and M. Furukawa: "Target Fragmentation of 145Pr
and 165Ho Induced by Heavy Projectiles", ibid.
44) Y. Kobayashi, T. Okada, F. Ambe,and K. Asai: "Magnetization and Mossbauer Effect Studies of Fe3-xRuxSi",
ibid.
45) K. Ida, Y. Itoh, A. Kinosita, and H.
Murakami: "The Study on Porous Silicon by Means of Positron Annihilation", ibid.
46) K. Fukutsu, T. Kanai, S. Koike, C.K.
Cho, T. Aruga, Y. Furusawa, and K.
Ando: "Response of Crypt Cell Surivalsof Mouse Intestine after Single Doses ofAccelerated Carbon-Ion with SpreadOut Bragg Peak", 35th Ann. Meet.
Jpn. Radiat. Res. Soc., Ohtsu, Oct.
(1992) .
47) T. Takatsuji, H. Okumura, T. Takahashi, F. Yatagai, and T. Kanai:-209-"Effect of Spatial Distribution of
Absorbed Energy to the Chromosome
Aberration", ibid.
48) K. Ijiri, T. Takahashi, and T. Kanai:"Effects of Carbon, Nitrogen, andArgon Ions on the Development of Fish
Embrios", ibid.
49) F. Yatagai, K. Nakano, H. Ikehata,
K. Eguchi, T. Kanai, and F. Hanaoka;"Understanding of Heavy-Ion Induced
Biological Damages: Approach from
Radiation Sensitivities of Mammalian
Cells", ibid.
50) M. Suzuki, M. Watanabe, K. Nakano, K. Suzuki, T. Kanai, and F.
Yatagai: "Biological Effects in Normal
Human Cells Induced by Accelerated
Carbon Ions", ibid.
51) K. Kimura, K. Morita, R. Nemoto, S.
Nakamura, and H. Kumagai: "Effect ofHigh-Density Excitation to Augerfree
Luminescence of Ion-Irradiated BaF z",
35th Conf. Radiat. Chern., Takasaki,
Oct. (1992).
52) K. Kimura: "Study on Depth-Resolved
Track Structure: Correlation between
UV -and VUV -Luminescences from IonIrradiated near Liquid Helium", ibid.
53) K. Ushida, A. Kira, K. Kimura, H.
Shibata, S. Tagawa, and Y. Yoshida:"y- Radiolysis of Ceramics as a Radiation Monitor", ibid.
54) K. Nakagawa, A. Ejiri, K. Kimura,
K. Tanaka, A. Kimura, N. Ohmori,and D. Nurdiawati: "Origin of Structureof Photocurrent Spectrum of Anthracene Doped in Non-Polar Solvents",ibid.
55) H. Murakami, Y. Itoh, and A. Kinoshita: "Positron Annihilation on Porous
Silicon", 47th Ann. Meet. Phys. Soc.
Jpn., Tokyo, Oct. (1992).
56) Y. Ohnishi, A. Moriguchi, T. Takahashi, and F. Yatagai: "Effects of HZEParticles on B. subtilis Spores", 6thAnn. Meet. Jpn. Soc. BioI. Sci. Space,
Sendai, Oct. (1992).
57) K. Ando, T. Kanai, S. Koike, Y.
Furusawa, K. Kasai, H. Itsukaichi ,H. Ohara, S. Furukawa, C.K. Cho ,M. Kimoto, M. Iizuka, T. Kiuchi, W.
Shimizu, T. Sugita, T. Aruga, N.
Hori, and F. Yatagai: "Biological
Effectiveness of Particle Beams on Cells
and Tissues", 3rd Symp. on Beams
Engineering of Advanced Material

Syntheses (BEAMS 1992), Tokyo,
Nov. (1992).
58) S. Ambe, S. Tanaka, Y. Kobayashi,
Y. Ohkubo, M. Iwamoto, H. Maeda,
M. Yanokura, and F. Ambe: "Study of
Selective Transport of Metal- Ions by
Means of a Supported Liquid Membrane
Using a Multitracer", Symp. on Membrane, Kyoto, Nov. (1992).
59) S. Shibata, K. Watari, Y. Noda, S.
Ambe, Y . Ohkubo, M. Iwamoto, Y.
Kobayashi, N. Takematsu, M. Yanokura, H. Maeda, and F. Ambe: "Application of Radioactive Multitracers to
Studies on Adsorption Behavior of Inorganic Elements on Solids from Solution" , 6th General Meet. J pn. Soc.
Adsorption, Utsunomiya, Nov. (1992).

5. Material analysis
1) M. Suzuki and T. Takahashi: "Proportional Scintillation Imaging Chamberand Its Application", 39th Spring Meet.
J pn. Soc. Appl. Phys., Funabashi,
Mar. (1992).
2) E. Uda, J. Kawai, and M. Uda: "Calculation of Kf3 X-Ray Spectra of Sulfur
Compounds by DV - Xa MolecularOrbital Method", 63th N atl. Meet.
Chern. Soc. Jpn. (Spring), Osaka,Mar. (1992).
3) S. Kubota, M. Hishida, M. Suzuki,
and J. Ruan (Gen): "Light Output andCollected Charge in Xenon-doped Liquid Argon", Int. Conf. on Liquid Radiation Detectors, Tokyo, Apr. (1992).
4) S. Kubota, M. Hishida, M. Suzuki,
and J. Ruan (Gen): "The Suppression of
the Slow Component in Xenon-doped
Liquid Argon Scintillation", ibid.
5) K. Maeda, Y. Sasa, M. Takami, andM. Uda: "Determination of the Surface
Angle of a Non-flat Target from the L/
K X-Ray Yield Ratio for Quantitative
PIXE Analysis", 3rd Int. Conf. on
Nuclear Microprobe Technology andApplications, Uppsala, Sweden, June
(1992) .
6) J. Kawai, K. Maeda, and T. Yamane:"High Resolution PIXE Using Imaging
Plate as a Position Sensitive Detector",
6th Int. Conf on Particle Induced X - Ray
Emission and its Analytical Applications, Tokyo, July (1992).
7) E. Uda, J. Kawai, and M. Uda: "Calculation of Sulfur Kf3 Spectra", ibid.

-210-8) T. Hanada, M. Mogi, J. Kawai, K.
Maeda, Y. Sasa, and M. Uda: "Intensity Analysis of Nickel La Spectra
Measured by a High - Resolution
Spectrometer for PIXE", ibid.
9) K. Ishii, K. Maeda, M. Takami , Y.
Sasa, M. Uda and S. Morita: "Continuous Background in Heavy Ion PIXE",
ibid.
10) Y. Nishide, E. Hayashi , K. Maeda,
Y. Sasa, and M. Uda: "PIXE Analysis
of Calcified Tissues by Use of a Combined X- Ray Absorber", ibid.
11) K. 1. Yoshida, H. Kusuyama, K.
Maeda, Y. Sasa, and M. Uda: "PIXE
Analysis of Human Spermatozoa: Comparative Studies of Composition of Spermatozoa from Different Degrees of Fertilizing Potential", ibid.
12) K. Suzuki, K. Maeda, Y. Sasa, A.
Okada, K. Sakamoto , and T. Ozawa:"Application of PIXE Analysis to
Source Indentification of KOSA Aerozol", ibid.
13) T. Isomura, K. Maeda, J. Kawai, M.
Kobayashi, M. Takami, and M. Uda:
"Materials Characterization by High
Resolution PIXE", ibid.
14) K. Maeda, Y. Sasa, and M. Uda:
"Effective Use of In- Air PIXE Analysis", ibid.
15) T. Tsunokami, Y. Sasa, R. Murai, K.
Maeda, I. Harigai, Y. Nakayama, S.
Yoshimura, T. Kikuchi, K. Sakurai,
and M. Uda: "Quantitative Analysis ofAncient Egyptian Pigments by External
PIXE", ibid.
16) S. Adachi, K. Takemoto, Y. Sasa,
and K. Maeda: "Fate of Inhaled Airborne Particles -PIXE for Hilar Glandand AAS for Lung Tissue", Int. Symp.
on Bio-PIXE , Sendai, July (1992) .
17) K. Kakihara, S. Gohhara, T. Nishijima, S. Itoh, K. Maeda, and Y. Sasa:"Metal Analysis of Liver Tissue by
PIXE in Patients with Liver Diseases",ibid.
18) M. Suzuki and T. Takahashi: "Track
Structure of Ionizing Radiation Observed by Proportional Scintillation Imaging Chamber", 1992 Fall Meet. Phys.
Soc. Jpn., Tokyo, Sept. (1992).
19) J. Kawai, E. Uda, and M. Uda: "DVXa Calculation of X-Ray Fluorescence
Spectra of the Third Period Elements" ,2nd Int. Conf. on Computer Applica-

tions to Materials and Molecular Science and Engineering, Yokohama,Sept. (1992).
20) M. Aratani, M. Yanokura, K. Tazaki, and K. Kaiho: "Profiling of
Heavy Elements in Clay Mineral Sampies", 36th Symp. on Radiochemistry,
Hachioji, Oct. (1992).
21) 1. Sugai , M. Oyaizu, M. Aratani, andM. Yanokura: "Total Characterizationof Self- Supporting Foils", ibid.
22) M. Yanokura, M. Aratani, and A.
Okada: "Nondestructive Analysis for
Hydrogen/Deuterium Ratio Using ERD
and NR Methods", ibid.
23) K. Kanazawa, M. Yanokura, and M.
Aratani: "Quantitative Measurement of-211-

Light Elements on the Surface of Vacuum Chamber Materials for Electron
Storage Rings", ibid.
24) T. Hanasaka, K. Watanabe, S. Yokouchi, Y. Niioka, and S. H. Be: "Outgassing Rate Measurement of BeCu andAlumina Sample" , 32th Vacuum Symp.
Jpn. (Sponsored by the Vacuum Societyof Japan), Osaka, Oct. (1992).
25) K. Maeda and J. Kawai: "InterferingLine in Energy - Dispersive X - Ray
Spectrometry: Radiative Auger Peak",
28th Meet. for X- Ray Chern. Anal.
Jpn., Tokyo, Nov. (1992).
26) J. Kawai, K. Maeda, and T. Yamane:"Imaging Plate X - Ray Emission
Spectrometer", ibid.

x. LIST OF SYMPOSIA

X. LIST OF SYMPOSIA(Jan. - Dec. 1992)
1) Studies of Condensed Matter Physics, Atomic Physics, Nuclear Chemistry, and BioMedical Science with the RIKEN Ring Cyclotron.
14 Jan. , Wako RIKEN, Metal Physics Lab.
2) Physics of High-Energy Heavy-Ion Collisions
23 Jan., Wako RIKEN, Cyclotron Lab.
3) Nuclear Physics at Intermediate Energy
24 Jan., Wako RIKEN, Linac Lab.
4) Nuclear Structure Studies using Radioactive Nuclear Beams
27 Jan., Wako RIKEN, Linac Lab.
5) Fusion Reaction and Fissions
28 Jan., Wako RIKEN, Cyclotron Lab.
6) Nuclear Physics with Radioactive Beam
29 Jan., Wako RIKEN, Radiation Lab.
7) Dinosaur Research in RIKEN
11 May, Wako RIKEN, Nuclear Chemistry Lab., Association of Vertebrate Paleontologists

in Japan8) Unstable Nuclei and Particles as Probes in Physics and Chemistry (UN3PC 92)
31 Aug. - 2 Sept., Wako RIKEN, Nuclear Chemistry Lab., The Chemical Society ofJapan, The Japan Society for Analytical Chemistry, The Japan Society of Applied Physics,
The Physical Society of Japan
9) Perspectives in Heavy Ion Physics (First Joint Italian-Japanese Meeting)
28 Sept. - 2 Oct., Catania, Italy, Accelerator Research Facility, Institute National Fisica
Nuclear (lNFN)
10) Nuclear Spectroscopy with Radioactive Beam
2.3 Nov., Wako RIKEN, Radiation Lab.
11) Muon Science 1992
9 Dec., Wako RIKEN, Metal Physics Lab.

-213-

XI. LIST OF SEMINARSXI. LIST OF SEMINARS(Jan. -Dec. 1992)"Pion Absorption and Short Range Correlations"Radiation Lab., Cyclotron Lab., andLinear Accelerator Lab.
1) H. Toki. Tokyo Metropolitan

Univ.
(Tokyo). 20 Jan.
"Scale Invariant N ambu and J ona - Lasinio
Model for Hadrons"2) N. Starkov. Lebedev Physical Institute.
Moscow (Russia). 5 Feb.
"The Properties and the Formation Probabilities of Charmed Nuclei"11) H. Sato, RIKEN, 8 June

"Systematics of Isotope Production Rates:
Fission Products and Their Barrier Penetration"12) J. K. P .

Lee, McGill Univ., Montreal(Canada), 10 June
"COMPLIS-ANew Laser Spectroscopic
Facility at ISOLDE, CERN"

3) K. Sumiyoshi. Tokyo Metropolitan Univ.

4)(Tokyo). 26 Feb.
"Neutron Star. Hot Neutron Star andSupernova with Equation of State in
Relativistic Field Theory"13) A. Nakamura. Waseda Univ. (Tokyo), 17

A. Kudryavtsev, ITEP, Moscow (Russia) ,11 Mar.
"Krell-Zel'dovich Phenomena in Particle
and Nuclear Physics"14) Y.

5) P. Kienle, GSI, Darmstadt (Germany), 16
Mar.
"Latest News about the GSI PositronLines"
6) M. Gai. Yale Univ., New Haven (USA),
25 Mar.
"Probing the Cosmos with Secondary(Radioactive) Beams"
7) P. Kienle, GSI, Darmstadt (Germany). 26
Mar.
"New Results from the GSI SIS/ESR"

June"Behavior of Hadrons at Finite Temperature"
Koike. Maryland Univ., Maryland(USA), 25 June
"Finite Temperature QCD Sum Rules
Reexamined: Rho/Omega/and A-I
Mesons"15) K. Takayanagi, Tokyo Denki Univ .
(Saitama), 26 June
"Isospin-dependent Effective Interaction
in Nucleon-nucleus Scattering"16) T. Otsuka, Univ. of Tokyo (Tokyo) , 6
July"Some Speculations on the Physics of
Unstable Neutron-Rich Nuclei"17) H. Ikegami, RCNP (Osaka), 7 July

"Cyclotron Maser Cooling of Electron and
Ion Beams"8) Y. Ogawa, Niigata Univ. (Niigata), 16
Apr.
"On Momentum Spectra of 9Li in Two
Neutron Removal Reactions of llLi"18) Zhang Qi-Ren, Peking Univ.,(China). 22 July
"On Quantum Bag Dynamics"

9) V. G. Soloviev, JINR. Dubna (Russia), 2219) K. Kato. Hokkaido Univ. (Hokkaido), 5

Apr.
"Microscopic Description of Vibrational
States in Deformed Nuclei"

Aug.
"Unstable Nuclei and Complex Scaling
Method"10) D. Ashery, Tel Aviv Univ., Tel Aviv

20) G. Bollen, Mainz Univ. (Germany), 26 Aug.
"Mass Measurements with Exotic Beams"(Israel), 28 Apr.

-215-

Peking21) H. Yabu, South Carolina Univ. (USA), 2
Sep.
"N ucleon Spin Structure in a Relativistic
Constituent Quark Model"

34) 1. Hamamoto, Univ. of Lund (Sweden), 18
Nov.
"Octupole Deformation in Large Fermion
System"22) M. Asakawa, Texas A&M Univ. (USA), 7
Sep.
"The MT Scaling in Dilepton Spectrum asa Signature for the Quark-Gluon Plasma"35) J. Chiba, KEK (Ibaraki), 25 Nov.
"Behavior of Delta in Nuclei"23) Jose A. Casado, Univ. de Santiago deCompostela (Spain), 16 Sep.
"Measurement of the Radii of Time
Dependent Chaotic Pion Sources"24) L.G. Liu, Zhongshan Univ. (China), 25 Sep.
"Studies of pO-cu Mixing"25) 1. Nomura, RIKEN, 7 Oct.
"Pion Absorption in Ge V Region: Beyond
the Meson Factories"26) M. Uehara, Saga Univ. (Saga), 19-20 Oct.
"The Chiral Soliton Model of a Nucleon"27) M. Thoennessen, NSCL, Michigan State
Univ. (USA), 23 Oct.
"Dissipation and the Population and
Decay of Compound Nuclei"28) H. Conzett, LBL (USA), 27 Oct.
"A Sensitive New Test of Time-Reversal
Invariance"29) 1. Katayama, INS (Tokyo), 29 Oct.
"A New Focusing and Cooling Device for
Ion from Ion Guide"30) T. N akatsukasa, Kyoto Univ. (Kyoto), 2
Nov.
"Octupole Correlations in Superdeformed
Nuclei"31) Y. K. Gambhir, IIT, Bombay (India), 5
Nov.
"Relativistic Mean Field Description of
Nuclear Properties"32) M. N. Harakeh, Vrije Univ., Amsterdam(the Netherlands), 6 Nov.
"Dipole Excitations in Inelastic Alpha
Scattering"33) V. Tsarev, Lebedev Physical Institute,
Moscow (Russia), 11 Nov.
"Cold Fusion Researches in Russia"

36) T. Kunihiro, Ryukoku Univ. (Shiga), 30
Nov.
"Chiral Phase Transition at Finite Tempera ture in QCD"
37) Y. Sakuragi, Osaka City Univ. (Osaka), 3
Dec.
"Is Coulomb Dissociation Method Applicable to Astrophysics?"38) G. D. Alton, Oak Ridge National Lab.
(USA), 3 Dec.
"The Radioactive Ion Beam Project at
The Oak Ridge National Lab."
39) Zhou Yizhong, Inst. of Atomic Energy(China), 7 Dec.
"The Study of Relativistic Heavy-Ion
Collisions with RBUU Theory"40) Liu Jianye, Inst. of Modern Physics(China), 7 Dec.
"Heavy-Ion Collision Theory with theMedium Effects and Momentum Dependent Interaction"41) Y. Yoshizawa, College of Industrial Technology (Hyogo), 7 Dec.
"Coulomb Excitation of Deformed Nuclei
and Future of Nuclear Spectroscopy"42) Zhang Xizen, Inst. of Atomic Energy(China), 9 Dec.
"Collective Spectrum of Octupole
Deformed System"43) T. Udagawa, Univ. of Texas, Austin(USA), 24 Dec.
"Delta and Its Decay in Nuclei"
Atomic Physics Lab.

1) K -I Kowari, Univ. British Columbia(Canada), 13 Jan.
"Moderation and Thermalization ofSubexcitation Electrons in Methane"2) M. Inokuti, ANL (USA), 13 Jan.
"Fano Factor of Argon for Electrons,-216-

Photons. and Alpha Particles""Recoil Ion Momentum Spectroscopy"3) C. Bhalla. Kansas State Univ. (USA). 18
Jan.
"Dielectronic Recombination and Resonance Transfer Excitation"8) D. Berenyi. Hungarian Academy Science(Hungary). 5 June

"Recent Results on the Cusp in the Spectrum of Electrons Emitted in Ion-Atom
Collisions"

4) B. D. DePaola. Kansas State Univ. (USA).

30 Jan.
"Charge Capture from a Laser Excited
Target"5) A. D. Bandrauk. Univ. Sherbrook(Canada). 28 Feb.
"Molecules in Intense Laser Field"
6) H. Schmidt-Backing. U ni v . Frankfurt(Germany). 2 Mar.
"Electron Emission in Heavy Ion-Atom
Collisions"

9) W. Meyerhof. Stanford Univ. (USA). 13
July"Atomic Clocks for Nuclear and Fission
Times"
10) P. H. Mokler. GSI (Germany). 14 July
"Atomic Collisions with Heavy Ions
(Recent Development at GSI)"
11) S. Hara. Tsukuba ColI. Tech .. 10 Sep.
"Theoretical Studies of Atomic Doubly-Excited States"

7) S. Lencinas. Univ. Frankfurt (Germany).
15 Apr.

-217-

XII. LIST OF PERSONNELXII. LIST OF PERSONNELRIKEN Accelerator Research Facility Personnel
ISHIHARA Masayasu E @: lE ~AWAY A Yohko(Facility Director)
Y ANO Y asushige ~ Jf !i ~(Vice Facility Director)~ ~ ~ T

(Vice Facility Director)

Linac Division
CHIBA Toshiya T ¥ flj ~HEMMI Masatake ~ J! l& ftt
KASE Masayuki 110 ~ ~ Z
MIY AZA WAY oshitoshi '§ ¥R f~ ~!i*CHIBA Yoshiaki T ¥ iff I!ij
IKEZA W A Eiji tfu ¥R ~KOHARA Shigeo IJ\ @:
J(

=

m

Ring Cyclotron Division=

FUJITA Jiro lJi B3~~
IKEGAMI Kumio ttB...t1L=~
KAGEY AMA Tadashi ~ LlJ
lE
KASE Masayuki 110. ~ Z
KUBO Toshiyuki :A 1* ~ $NAKAGAWA Takahide rp ]'1 ~YOKOYAMA Ichiro
LlJ ~ ~~*m

GOTO Akira 1& lJi~*
INABE Naohito f~ JZ1 raJ A
KAMIGAITO Osamu ...ttl[5i-{~~
KOHARA Shigeo IJ\ @: ~ J(
NAGASE Makoto ~ ~~OGIW ARA Kiyoshi M< @:mExperimental Support Division
ICHIHARA Takashi m@:
1j[
KANAI Yasuyuki ~ it 1* Z
KUMAGAI Hidekazu ~~ ~W
MORITA Kosuke ~ B3 ~ ft
W A T AN ABE Yasushi ?1t j§
Y A T AGAI Fumio ~B3ffit)(J(*'*

KAMBARA Tadashi flft @:IE
KOBAYASHI Toshio IJ\{~ 1Rft*
MA TSUZAKI Teiichiro t)}tlffijfJtm~~
OHKUBO Yoshitaka *~1*~~
YANOKURA Minoru ~Jf~ ~**Radioisotope Facilities Division
AMBE Fumitoshi !i $ Jt 1fx:*
KOBAYASHI Yoshio IJ\~ ~**IWAMOTO Masako :5

* T

s B3

1§t**

lE

Administration Staff
NAKAMURA ToshikorpM t L-T

YOSHIDA Tohru

Steering Committee
AMBEFumitoshi !i $ Jt 1fl:
CHIBA Yoshiaki T ¥ iff I!ij
HANAOKA Fumio 1E IUij Jt :b.t
ISHIHARA Masayasu E @: lE ~KA TSUMA T A Koichi J19j X tW; ~KOBA YASHI Toshio IJ\
f~ fit
MA TSUOKA Masaru t)} IUij
J19j
NAGAMINE Kanetada 7k ~ ~ ,liS',***Group Leader

AWAYA Yohko ~ J.¥. ~ T
GOTO Akira 1& lJi~
INAMURA Takashi f~ M
.Ejf
KAMITSUBO Hiromichi ...t P¥ 7ff. J!!
KIRA Akira~~
KUMAGAI N oritaka ff~ ~ ~ ~MIY AZAWAY oshitoshi '§ ¥R {~ .~!i
TAKAHASHI Tan ~ ~.§.

s** Administrative Manager-219-

T AKAMI Michio
YAGI Eiichi J\

rWJ ~ J!! ~**T ANIHA T A Isao
YANO Yasushige~~ 1:IH ~ 7( *~!f!i:mScientific and Engineering Personnel
Cosmic Radiation Laboratory
IMAI Takashi~ #~KOHNO Tsuyoshi rBJ!f~(Visitors)
HASEBE Nobuyuki ~~$ffifr (Fac. Gen. Educ., Ehime Univ.)
KASHIWAGI Toshisuke ;f8
flJ 11'- (Sci. Eng. Res. Lab., Waseda Univ.)
KA TO Chihiro 110 JJi T ~MUNAKATA Kazuoki 7# {~ ~ ~ (Fac. Sci., Shinshu Univ.)
MURAKAMI Hiroyuki M L ~ Z (Fac. Sci., Rikkyo Univ.)
NAGATA Katsuaki 7J< 83 1m ~ (Fac. Eng., Tamagawa Univ.)r¥ (Fac. Sci., Rikkyo Univ.)
NAKAMOTO Atsushi cP
YANAGIMACHI Tomoki WP IHJ Jl~ W (Fac. Sci., Rikkyo Univ.)**(Students)
FUJIKI Kenichi JJi~ ~ (Fac. Sci., Ehime Univ.)
ITO Tomoyuki W JJi 1m 1T (Fac. Sci. Eng., Waseda Univ.)
ITSUMI Norifumi ~ ~ 11 ~ (Fac. Sci. Eng., Waseda Univ.)~ (Fac. Sci., Ehime Univ.)
MORIY A Hitoshi ~ ~SHINO Tomoaki 1t¥
9& ~ (Fac. Sci. Eng., Waseda Univ.)*

Cyclotron Laboratory
DA TE Schin W ~{$FU JIT A Shin JJi EB~
HARADA Toru JJ.R 83
ill
INABE Naohito f18 ill fi!ij A.
JIN Wei-Guo ~f1tJ 00
KAMIGAITO Osamu ..t.:t!!~{~~KUBO Toshiyuki ::A. 1* ffi ¥NAGASE Makoto ~ 1fj~
NAKAJIMA Shunji cP Nb ~OGIWARA Kiyoshi ~ ~m
SAITO Motozo "li JJi Ml =.
SOUTOME Kouichi !f.Zft:7'6W AKASUGI Masanori ;fi ~ l§ ~YANO Yasushige ~!f!i:m==

FUJITA Jiro JJi 83~~
GOTO Akira f~ J1i~
IKEGAMI Kumio tfft..t.:tL=.~INAMURA Takashi fm M ~KAGEY AMA Tadashi ~ Llr
IE
KOHARA Shigeo /J\ ~ :m 7(
MORITA Kosuke ~ 83 ~ 11'NAKAGAWA Takahide cp}ll ~NAKANISHI N oriyoshi cp ~ *,c :g
OHTA Shigemi =*= 83 iYl ~SHIKA T A Takashi IZB 15 ~ ~SUGANUMA Hideo 11
7(
YAMAJI Shuhei U1 ~ ~ ~YOKOYAMA Ichiro f1i Llr ~ ~~*m*(Visitors)
ABE Yasuhisa Ifri] $ ~::A. (Res. Inst. Funda. Phys., Kyoto Univ.)~ (Res. Lab. Nucl. Reactors, Tokyo Inst. Tech.)
ARAI Eiichi ~ #EJIRI Hiroyasu ¥I m 7R ~ (Dep. Phys., Osaka Univ.)
FUJIOKA Manabu J1i ffijJ~ (Cyclotron Radioisot. Cent., Tohoku Univ.)
FUJISAW A Takashi J1i ¥R rWJ ~ (Denki Kogyo Co. Ltd.)
FUJITA Yoshitaka J1i 83 {* ~ (Dep. Phys., Osaka Univ.)
FUKUMOTO Sadayoshi m ~ . ~ (KEK)
FURUNO Kohei il!f Jij. ~ (Inst. Phys. Tandem Accel. Cent., Univ. Tsukuba)**·Chairperson-220-

HASHIMOTO Osamu ":£$:m (lnst. Nucl. Study, Tokyo Univ.)
HAT ANAKA Kichiji :tm r:p E m (RCNP, Osaka Univ.)
HATSUKAWA Yuichi fJ]}l1 fIt (JAERI, TokaD
HAYANO Ryugo .!f!. If ft 1i (Dep. Phys., Tokyo Univ.)
HEIGUCHI Kazuhiko -¥ D *0 ~ (Graduate Sch. of Sci. & Tech., Niigata Univ.)
HIRAO Yasuo -¥ ~ ~ ~ (Nat. Inst. Radiol. Sci.)
HORIGUCHI Takayoshi :!1ffi D ~.S! (Dep. Phys., Hiroshima Univ.)
HORIUCHI Hisashi :!1ffipglJ' ~ L- (Dep. Phys., Kyoto Univ.)
IKEDA Kiyomi nB 83 m- ~ (Dep. Phys., Niigata Univ.)
IKEDA Nobuo nB 83 1$ 7( (lnst. Nucl. Study, Tokyo Univ.)~ (RCNP, Osaka Univ.)
IKEGAMI Hidetsugu nB..t
INOUE Makoto 1* L
Fa (RCNP, Osaka Univ.)
ISHIZUKA Takeo 15 ~ j\:!13 (Dep. Phys., Saitama Univ.)
Iffl (J apan Atomic Energy Res. Inst.)
IWAMOTO Akira :E-:£$:IWASHIT A Yoshihisa :E- T j!j!A. (lnst. Chern. Res., Kyoto Univ.)
KAMEY AMA Hirobumi .. LlI tS- Jt (Dep. Phys., Chiba Keizai Jr. ColI.)
KAMIMURA Masayasu L;ff.IE(Dep. Phys., Kyushu Univ.)
g 7( (Dep. Phys., Osaka Univ.)
KANMURI Tetsuo E
KA T A YAMA Ichiro ):f W- ~~ (RCNP, Osaka Univ.)
KATORI Kenji Jm 1& ~(Dep. Phys., Osaka Univ.)
KA TO Kiyoshi 110 JJi ~ 15 (Dep. Phys., Hokkaido Univ.)~ (Dep. Phys., Toho Univ.)
KATSURAGAWA Hidetsugu ~ JII
KAWAI Mitsuji JII ft)l[; ~ (Dep. Phys., Kyushu Univ.)
KIKUCHI Fumio ~ nB Jt ~ (ColI. Arts Sci., Univ. Tokyo)
KOBA YASHI Shinsaku ;j\~ 1'F (Dep. Phys., Kyoto Univ.)~ (Univ. Electro-Commun.)
KOHMOTO Susumu iilJ:£$:
KOHMOTO Toshiro iilJ:£$: tfz ~~ (Dep. Phys., Kyoto Univ.)
KOIZUMI Mitsuo IJ\ jJ{ )I[; ~ (Dep. Phys., Hiroshima Univ.)
KONDOU Michiya JlI J1i jg i:f! (RCNP, Osaka Univ.)
KOSAKO Toshiso IJVftcr:!ltfztt (Atomic Energy Res. Cent., Univ. Tokyo)
KUDO Hisaaki I J1i !A. Iffl (Dep. Chern., Niigata Univ.)
KUROY ANAGI Tokihiro J.HPD~§::*: (Dep. Phys., Kyushu Univ.)
LEE Sanmu*13 N, (Dep. Phys., Univ. Tsukuba)
LI Zhuxia (Atomic Energy Sci. & Tech.)
MARUMORI Toshio :tL ~ ~ 7( (Dep. Phys., Univ. Tsukuba)
MA TSUKI Seishi;f'~fiE ~ (RCNP, Osaka Univ.)
MA TSUSE Takehiro ;f'~ iii ;t ~ (Dep. Phys., Shinshu Univ.)
MATSUYANAGI Kenichi ;f'~:fW lUf (Dep. Phys., Kyoto Univ.)
MINAMISONO Tadanori
til J~' ~Ij (Dep. Phys., Osaka Univ.)
MIURA Iwao -=?m
(RCNP, Osaka Univ.)~ (Fac. ScL, Osaka Univ.)
MIY AMURA Osamu g;fj
MIY A TAKE Hiroari g 1ft
i:f! (Fac. Sci., Osaka Univ.)
MORI Yoshiharu ~~ m (KEK)MURAKAMI Tetsuya t1 L g i:f! (Dep. Phys., Kyoto Univ.)
MURAOKA Mitsuo ;fj ~ )I[; ~ (Dep. Educat., Chiba Univ.)
MURA YAMA Toshiyuki ;fj LlI flj ¥ (Tokyo Univ. Mercantil Marine)
IL\ (Sch. Sci & EngL, Waseda Univ.)
MUROTANI Shin ~ ~NAGAI Yasuki 7k 1* ~ ~ (Dep. Appl. Phys., Tokyo Inst. Technol.)
NAKAHARA Hiromichi r:p ~ iJ,b jg (Dep. Chern., Tokyo Metrop. Univ.)(KEK)
NAKAI Koji r:p 1* ~NAKAMURA Ichiro r:p;ff~~(Dep. Phys., Saitama Univ.)
NAKAMURA Takashi r:p;fj ri16 p] (Cyclotron Radioisot. Cent., Tohoku Univ.)
NIITA Koji t1*83~= (Dep. Phys., Univ. of Giessen, Giessen)
NOMURA Toru If t1
Jjf (Inst. Nucl. Study, Univ. Tokyo)
OGATA Hiroshi IJ\ 1.ij[ (RCNP, Osaka Univ.)
ONISHI N aoki ::*: ~ 1R ~ (Dep. Phys., ColI. Gen. Educ., Univ. Tokyo)

*

*

=

*

**

*

*

*m

*

=m

-221-

OSUGA Toshiaki *~~1ljj[1Y3 (Col . Art & Sci., Chiba Univ.)
PU YUE HU rm~ t!f. (Dep . Phys., U niv . Tsukuba)
SAKAI Hideyuki ~:4 ~ iT (Dep. Phys., Univ. Tokyo)
SASAGAWA Tatsuya iff}ll ~ 51]\ (Dep . Phys., Tohoku Univ.)
SATOU Kenichi ftc Yj. (Dep. Phys., Tohoku ColI. Pharm.)
SEKINE Toshiaki ~ fi f~ IY3 (JAERI, Tokai)
SHIKAZONO Naoki ~ III@: ~ (JAERI, Tokai)
SHIMOMURA Koichiro rf1i15--~~ (RCNP, Osaka Univ.)
SHINOZUKA Tsutomu fll ~~ (Cyclotron Radioisot. Cent., Tohoku Univ.)
SUEKI Keisuke
Fg: fr (lnst. Nucl. Study, Univ . Tokyo)
SUGAI Isao 1E:4
J!,!{ (lnst. Nucl. Study, Univ. Tokyo)
SUMIYOSHI Hiroyuki fj: E JZ iT (Matsusho-Gakuen Junior Col.)T AGISHI Yoshihiro EB W R 7J;. (Tandem Accl . Cent., Univ. Tsukuba)
T AKADA Kenjiro ~ B3{9t{X~~ (Dep . Phys., Kyushu Univ.)
T AKEMASA Tadashi j\ i& jt ± (Dep. Phys., Saga Univ.)
T AKIGA WAN oboru ~}l1
g:j- (Dep. Phys., Tohoku Univ.)
T AMAGAKI Ryozo 3l.:f:.§: ~.=:. (Dep. Phys., Kyoto Univ.)
TANAKA Jinichi EB $ t=(lnst. Nucl. Study, Univ. Tokyo)
TOHY AMA Mitsuru ~ UJ
fpiti (Dep . Phys., Kyorin Univ.)
TOMIMASU Takio Mm~~7( (Electro Tech. Lab.)TORIY AMA Tamotsu ,~UJ
1* (Dep . Appl. Phys., Tokyo Inst. Technol.)
TSUNEMOTO Hiroshi t~:7C
1W (N atl. Inst. Radio . Sci.)W ADA Michiharu *0 EB J1i(Dep . Phys., Tohoku Univ . )W AKAI Masamichi sE:4 IE J1i (Dep . Phys., Osaka Univ . )WANG Zhen.:E
1i (lnst. Modern Phys., Academia Sinica)
Y AMANOUCHI Mikio UJ ~ ~ fit (Tandem Accel. Cent., Univ. Tsukuba)
YAMAZAKI Takashi UJ Iifflf
ft (RCNP , Osaka Univ . )YOSHIDA Nobuaki E B3 W ~ (Dep . Phys., Univ. Tokyo)
YOSHIDA Shiro
B3 J~' ~~ (Dep. Phys., T ohoku Univ.)
YOSHINAGA Naotaka E 7J< r% ~ (Comput. Cent., Univ. Tokyo)

**

m

m

a

(Students)
ARIGA Takehiro ~ ~ {9t 1W (Dep. Phys., Saitama Univ.)
FUKASHIRO Yasuyuki ~ {i; ~ Z (Dep . Phys., Tohoku Univ.)
FURUYA Shinji tl;fr {B ~ (Dep. Appl. Phys., Tokyo Inst. Technol.)
HAMADA Shingo 7~ rn A't-a- (Dep. Nucl. Eng., Kyoto Univ.)
HIRASAWA Junichiro ~~7~-~~ (Dep . Appl. Phys., Tokyo Inst. Technol.)
KASHIWABARA Taketoffi'{ ~ A
(Dep. Phys., Toho Univ.)
KA TOU Haruhiko DO Bi mJfE (Dep. Phys., Chuo Univ.)
KOBAYASHI Takayuki IJ\ # .. Z (Dep . Chern., Tokyo Metrop. Univ.)
KUMAGAI Kenji ~~;fr ~(Dep. Phys., Hiroshima Univ.)
KURAMOTO Takeshi ~ft:\ ~ (Dep . Phys., Tokyo Univ.)
MARUYAMA Toshiki A UJ ffx. ~ (Dep . Phys., Kyoto Univ.)
NAKAOKA Masaya $ /tqj IE ~ (Dep . Phys., Saitama Univ.)
NISHINAKA Ichiro g:g $ - W3 (Dep. Phys., Tokyo Metrop. Univ.)
OGAWA Izumi Ij\}l1~ (Dep. Phys., Kyoto Univ.)
OONISHI Akira *- iffi'
IY3 (Dep. Phys., Kyoto Univ.)
OOSAKI Toshiro *- Iifflf ffx. ~~ (Dep. App!. Phys., Tokyo Inst. Technol.)
SEINO Satoshi
Je't (Dep. Appl. P hys., Tokyo Inst. Techno!.)SENOO Kenichi ~ ~ .If (Dep . Appl. Phys., Tokyo Inst. Techno!.)SUNAOSHI Hitoshi ;uj> ¥fJ
f= (Dep. P hys., Tohoku Univ . )SUZUKI Katsuhiro ~MJ: 1W (Dep . Phys., Kyoto Univ.)
TAKAYANAGI Masao ~.fPIJ ~ 7( (Dep . Phys., Toho Univ.)
TAKEDA Kenji 1t EB .If ~ (Dep . Appl. Phys., Tokyo Inst. Technol.)
T ANIKA W A Masashi ;fr}ll MJ: ~ (Dep . Phys., Tokyo Metrop. Univ.)WAKUI Takashi ~:4it (Dep. Phys., Toho Univ.)

m

*=

m!f

*

*

-222-

WATANABE Koutarou?1lm~*f1~(Dep. Appl. Phys., Tokyo Inst. Technol.)Linear Accelerator Laboratory

CHIBA Toshiya T ¥ flj ~FU JIMAKI Masaki lJj ~ .IE mt
HIRENZAKI Satoru jtJ!!~
KASE Masayuki 110 ~ l§ Z
KUMAGAI Hidekazu 1f~ ~fD
OZAWA Akira 11\ tR
JJi
TANIHATA Isao ~ mI ~ 7(
YANOKURA Minoru 9(!f:it ~m*

CHIBA Yoshiaki T ¥ fjf ~HEMMI Masatake ~ ~ iI& j\
IKEZAWA Eiji nB tR ~KOBA YASHI Toshio 11\ # f~ 1Lft
MIY AZA WAY oshitoshi '§ tR ft ~!(SUZUKI Takeshi ~00
TONUMA Tadao p.IE 1Lft
YOSHIDA Koichi E ill :J'G -=*m(Visitors)
ALOKSANDROV D. V. (Kurochatov Inst.)
FUJIWARA Mamoru lJj ~~ (RCNP, Osaka Univ.)
HIRAT A Daisy (CT A, Inst. Estudos Avancados, Brasil)
HURUTANI Keiichi t; ~ ~ (Fac. Sci., Sci. Univ. Tokyo)
ITO Noriaki W J1j • Bf{ (Dep. Cryst. Mater., Nagoya Univ.)(KEK)
KANAZAWA Kenichi ~ ~ 00 KA TORI Kenji ..IJig ~ ~(Fac. Sci., Osaka Univ.)nWi (Sci. Eng. Res. Lab., Waseda Univ.)
KIKUCHI Jun ~ nB
KIMURA Kikuo *M~~Hi (Fac. Eng., Nagasaki Inst. Appl. Sci.)
KORCHENINNIKOV A. A. (Kurochatov Inst.)
MATUOKA Nobuyuki f'~ flifl f$ fj (Res. Centr. Nuc1. Phys., Osaka Univ.)
MOON Chang-Bun (Seoul Univ.)
MURAOKA Mituo tt flifl :J'G ~ (ColI. Arts Sci., Chiba Univ.)
NIKOLSKI E. Y. (Kurochatov Inst.)
OBUTI Marcia M. (Sao Paulo Univ.; Saitama Univ.)
OGAWA Kengo 1]\" I ~.:g: (ColI. Arts Sci., Chiba Univ.)
OGLOBLIN Alexei (Kurochatov Inst.)
OMATA Kazuo 1]\ ~ fD ~ (Inst. Nuc1 . Study, Univ. Tokyo)
SAGAWA Hiroyuki 1tc" I sb ¥ (Fac. Sci., Univ. Tokyo)
SAKAI Hideyuki ~ 1* ~ ff (Fac. Sci., Univ. Tokyo)
SUDA Toshimi ~ ill flj ~ (Fac. Sci., Tohoku Univ.)
SUGAWARA Masahiko 1f In: €§ ~ (Fundam. Sci., Chiba Inst. Technol.)~(Fac. Sci., Niigata Univ.)
SUZUKI Yasuyuki ~YAMAGUCHI Hiromi UJ 0 m~ (Sci. Eng. Res. Lab., Waseda Univ.)=* z

Radiation Laboratory

FERRAGUT Alain
ISHIHARA Masayasu E In: .IE ~KONNO Satoshi ~ If~
SUZUKI Masayo ~l§ t!tTAN AKA Kazuhiro 83 ~ fD 7i:.
WAT AN ABE Yasushi ?1l jI~*

ICHIHARA Takashi mIn:~IZUMO Koichi lli ~ J't NOMURA Izumi If tt fD ~TAKAHASHI Tan rWJ ~.§.
TENDOW Yoshihiko ;R. J!! 7!i ~YOSHIDA Atsushi
83~a(Visitors)
ABE Yasuhisa /WJ $ ~ ~ (Res . Inst. Fundam. Phys., Kyoto Univ.)•(Dep. Appl. Phys., Tokyo Inst. Techno!.)ADACHI Minoru JE fL
ANDO Yoshiaki !fi lJj ~. (Dep. Phys., Rikkyo Univ.)
APRILE Elena (Columbia Univ., U.S.A)
ASAHI Koichiro it!! *1t-f1~ (Fac . Sci., Tokyo Inst. Technol.)
BECK F. A . (Groupe RSN, Strasbourg, France)-223-

BROGLIA R. (Milano Univ., Italy)
DELBAR Thierry, JM (Univ. Catholique de Louvain, Belgium)
J~ ~ (Sci. Eng. Res. Lab., Waseda Univ.)
DOKE Tadayoshi J!l
FLOCARD Hubert (lnst. Phys. Nuc!., Orsay, France)
FUCHI Yoshihide ~JW(lnst. Nuel. Study, Univ. Tokyo)
FUJIOKA Manabu Hi rm.J~
(Dep. Phys., Tohoku Univ.)
FUKUDA Mitsunori 1M EB :7'6 JIIfi (Fac. Sci., Osaka Univ.)
FUKUDA Tomokazu 1M EB ~ *0 (Inst. Nuel. Study, Univ. Tokyo)
GAL Moche (Yale Univ., U.S.A.)
GONO Yasuyuki ~. ~ Z (Dep. Phys., Kyushu Univ.)
GUY Y. Bizard (CAEN Univ., France)
HAMAMOTO Ikuko ~;$: rf T (Lund Univ. Sweden)
HASEGAWA Takeo ~~)lIJi\~ (Fac. Eng., Miyazaki Univ.)
HASHIZUME Akira ~ J1\
W3 (Japan Atomic Energy Relations Organization)
HITACHI Akira f§ teJl[ (Sci. Eng. Res. Lab., Waseda Univ.)
Ji\ (ColI. Arts Sci., Univ. Tokyo)
ICHIMURA Munetake mf1~ *0 7( (Fac. Sci., Rikkyo Univ.)
IEKI Kazuo
IJIRI Kenichi :#jI (Radioisot., Cent., Univ. Tokyo)
ISHIDA N obumichi E EB {$ J!l (Seikei Univ.)
ISHIKAWA Masanobu E J II ~(Tokyo Univ. Fisheries)
IW ASAKI Hiroyuki :fi ~ 1* 1T (KEK)
KANEYUKI Kenji ~ 1T 1Jt tEl (Fac. Sci., Tokyo Inst. Techno!.)KASAGI Jirohta ~*tElfl~:;;t (Lab. Nuel. ScL, Tohoku Univ.)
KASAL Kiyomi ~:# ~ ~ (N atl. Inst. Radiol. Sci.)
KATAYAMA Ichiro Jt W - fl~ (lnst. N uel. Study, Univ . Tokyo)
KA TO Seigo 110 Hi ~:g: (Fac. Educ., Yamagata Univ.)
KA TORI Kenji 1m.I:& ~(Fac. Sci., Osaka Univ.)
KAWAKAMI Hirokane }II L 7Z. ~ (lnst. Nuel. Study, Univ. Tokyo)
KAWASHIMA Hideo }II ~ ~ 1lI (lnst. Nuel. Study, Univ. Tokyo)
JIIfi (Sci. Eng. Res. Lab., Waseda Uni v . )KIKU CHI J un ~ ¥tB
KIM Hee J. (Oak Ridge Nat!. Lab., U.S.A.)KIM Jong-Chan ~• If (Seoul Nat!. Univ., Korea)
KISHIDA Takashi J$ EB~ (Fac. Sci., Univ. Tokyo)
KIT AHARA Yoshitaka ~t ~ ~ q: (Hoya Corp.)
KIT AO Kensuke W37 ~.WJ (N atl. lnst. Radiol. Sci.)
KOMAGA T A Kazuyuki ~ % *0 1T (Asahi Glass Co., Ltd.)KONDO Takahiko JlIHi~j:ttJ (KEK)KUBONO Shigeru ~*!f ~ (Inst. Nuel. Study, Univ. Tokyo)
KUBOTA Shinzou mEB ffi(Fac. Sci., Rikkyo Univ.)
KUSAKARI Hideshige 1¥. jlJ ~ ~ (Fac. Educ., Chiba Univ.)
LEE Sang Mu;f~ ~ (lnst. Phys., Univ. Tsukuba)
LIU Jian Ye (lnst. Mod. Phys., Acad. Sinica, China)
LIU Lyan Gan i1J~ ~ (Zhong Shan Univ., China)
MAEDA Kazushige iW EB ~ ~ (ColI. Gen. Educ., Tohoku Univ.)
MASUDA Kimiaki :Ii EB 1} ~ (Saitama ColI. Health)Ji\ (KEK)
MA TSUDA Takeshi t'~ EB(Dep. Phys., Kyoto Univ.)
MATSUYANAGl Kenichi t'~ lPP 1Vf ~ ~ (Korea Atomic Energy Res. Inst., Korea)
MIN Byung- Joo 00
MIT ARAI Shiro 1JEIJ~¥$'G~fl~ (Dep. Phys., Kyushu Univ.)
MIYACHI Takashi '§:ttl!
q: (lnst. Nuel. Study, Univ. Tokyo)
MIY A TAKE Hiroari '§ Ji\ f ili (ColI. Gen. Educ., Osaka Univ.)
MORIKAWA Tsuneyasu ~ J II tg !Ji
MORINOBU Shunpei ~ ffi {~~ (Dep. Phys., Kyushu Univ.)~ (Fac. Sci., Rikkyo Univ.)
MOTOBA YASHI Tohru ;;$:MOTTELSON Ben R. (NORDITA, Copenhagen, Denmark)
MUKERJEE Reshmi (Columbia Univ., U.S.A.)

*

*

*

*m

*c

=

-=

*

**

-224-

MURAKAMI Takeshi fj L
{jl (N atl. lost. Radiol. Sci.)
NAGAI Yasuki 7k tt: ~;fM (Fac. Sci., Tokyo lost. Technol.)~ ~ j( (Dep. Phys., Univ. Tsukuba)
NAGASHIMA Yasuo
NAKAJIMA Mitsuo $ ~ Jt j( (Graduate Sch. Nagatsuda, Tokyo lost. Technol.)
NAKAMURA Syougo $ fj .IE:g (Fac. Educ., Yokohama Nat. Univ.)
NAKAYAMA Shintaro $wffi*~~ (ColI. Gen. Educ., Tokushima Univ.)
NEUGART Rainer (Mainz Univ. German)~ (Fac. Sci., Tokyo lost. Technol.)
NIIZEKI Takashi if ~NORO Tetsuo !Y g 1& j( (RCNP, Osaka Univ.)
OGAWA Masao 1]\)11 ~ ~ (Graduate Sch. Nagatsuda, Tokyo lost. Technol.)
OGURA Koichi ;j\ it Rt. (ColI. Indus. Techno!., Nihon Univ.)
OHNUMA Hajime
m -m (Fac. Sci., Tokyo lost. Technol.)
OHTSUKA Takaharu~ ~(Fac. Sci., Univ. Tokyo)
OKAMURA Hiroyuki ~ fj "5b. Z (Fac. Sci., Univ. Tokyo)
ORIHARA Hikonojo ~mt~Z7J( (Cyclotron and Radioisot. Cent., Tohoku Univ.)
OSHIMA Masumi~ ~ ffl: (J apan Atomic Energy Res. Inst.)~ (Tokyo Univ. Fisheries)
OSHIRO Takashi ~ ~OYAIZU Michihiro ;j\:WP?$Jt~ (lnst. Nucl. Study, Univ. Tokyo)
QU Yun-he fttl
~ ri.TJ (lnst. High Energy Phys., Chinese Acad. Sci., China)
J! tEl (Dep. Phys., Rikkyo Univ.)
RUAN (GEN) Jian-zhi 1%
SAKAGUCHI Harutaka ~ 0 tEl ~ (Dep. Phys., Kyoto Univ.)
SAKAI Mitsuo J& tt: 7't j( (lnst. Nucl. Study, Univ. Tokyo)
SAKAI Yoshihide ~ tt: ~ ~ (KEK))j1J;.
(Seikei Univ.)
SA TO Hiroshi ftc J1j
SHIBAMURA Eido ~ fj ~:@: (Saitama ColI. Health)
SHIMIZU Hajime
71< II (Fac. Educ., Yamagata Univ.)
7.1< ~ Jt (Dep. Phys., Kyushu Univ.)
SHIMIZU Yoshifumi
SHIMODA Tadashi r 83
.IE (ColI. Gen. Educ., Osaka Univ.)~ (Dep. Phys., Rikkyo Univ.)
SHIMOURA Susumu r 00
(Dep. Phys., Rikkyo Univ.)
SHIRA TO Shoji B ± wJ\
SHIROY AMA Masaki ~ W.IE;fM (Asahi Glass Co., Ltd.)SUEKANE Fumihiko~ Jt ~ (Fac. Sci., Tohoku Univ.)
SUGAW ARA Masahiko ;g Jm {§ ~ (Chiba lost. Technol.)SUZUKI Yasuyuki ~1i Z (Dep. Phys., Niigata Univ.)
T AKADA Eiichi ~ 83
(N atl. lost. Radiol. Sci.)
TAKAHASHI Noriaki ~ ~. f!I3 (ColI. Gen. Educ., Osaka Univ.)
TAKAKU Shinsaku ~ 7-. m11= (Inst. Nucl. Study, Univ. Tokyo)
H (Dep. Phys., Tohoku Univ.)
TAKIGAWA Noboru ~)l1
TANAKA Masahiko 83 $ ~"& (Inst. Nucl . Study, Univ. Tokyo)
T ANIMORI Tohru ~ ~Ji (Fac. Sci., Tokyo lost. Technol.)TAO Kazuyuki:i:¥tD Z (Radioisot. Cent., Univ. Tokyo)
TOKI Hiroshi ± I/&: it (Dep. Phys., Tokyo Metrop. Univ.)
TOYOKA W A Hidenori II) II ~ WI! (lnst. Phys., Univ. Tsukuba)
TSAREV V. (Lebedev Phys. Inst., Moscow)
UNO Masahiro ~!Y.IE 7.l. (The Ministry of Education)
UNNO Yoshinobu #ij mY ft 1"§ (KEK)W AT ANA BE Yasushi ?1t ill ~ ~ (Fac. Sci., Tokyo lost. Technol.)
YAMAYA Takashi W m.
~ (Dep. Phys., Tohoku Univ.)
YA TO Osamu 5( ~tEl (Kagoshima Agr. Exp. Stn.)YOSHIDA Kazuo E 83 tD j( (Hoya Corp.)
YOSHINAGA Naotaka -a- 7J< 1% ~ (Saitama Univ.)YOSOI Masaru W~tt: ~ (Dep. Phys., Kyoto Univ.)
YUT A Haruo ~ 83 ~ tit (Fac. Sci., Tohoku Univ.)
ZHANG Yu-hu ~.:li r.Jf. (Inst. Mod. Phys., Acad. Sin., China)
ZHU Yongtai ~7k ~ (lnst. Mod. Phys., Acad. Sin., China)

*

"* "*

m

"*

m
m

*

=

** -

-225-

(Students)
AKEBOSHI Yoshihiro IY3 £ !l ~ (Fac. Sci., Tokyo Inst. Technol.)
AOI N ori W #15 (Fac. Sci., Univ. Tokyo)
BEN Sei T
lE (Sch. Sci. Eng., Waseda Univ.)
CHAE Soo-Joh (Seoul Univ., Korea)
DOl Masashi ± # ~ ~ (Fac. Sci., Tokyo Inst. Technol.)
DOKI Yasuhiro ± ~c f>l if (Fac. Sci., Univ. Tokyo)
FRANCE Jr. Ralph Hayward (Yale Univ., U.S.A.)
FURUT AKA Kazuyoshi t5 rWb fD:fJi (Fac. Sci., Tokyo Inst. Techno!.)FUT AMI Yasuyuki~ f>l Z(Inst. Phys., Univ. Tsukuba)
GUIMARAESValdir (Inst. Nucl. Study, Univ. Tokyo)
HAHN Kevin I (Yale Univ., U.S.A.)
HARADA Masaki
EEl {!§ W (Fac. Sci., Tokyo Inst. Techno!.)
HASEGAWA Yoji :R~}lIJMfP] (Fac. Sci., Tohoku Univ.)
HASUIKE Katsuhito ~ tfu Mj A (Sch. Sci. Eng., Waseda Univ.)
HONJO Yoshio ;$: ~ ~ 7( (Inst. Phys., Univ. Tsukuba)
HORI Yoichi #ffi
~ ~(Fac. Sci., Tokyo Inst. Techno!.)HOSAKA Masahito 1* ~ ~ A (Cyclotron and Radioisot. Cent., Tohoku Univ.)
ICHIGE Masayuki=.§ lE z (Sch. Sci. Eng., Waseda Univ.)
IDEGUCHI Eiji #=¥O*til (Dep. Phys., Kyushu Univ.)
IKEDA Yasufumi tfu EEl ~ X (Dep. Phys., Rikkyo Univ.)
ISHIDA Satoru 15 EEl'ttf (Fac. Sci., Univ. Tokyo)
1Vf (Sch. Sci. Eng., Waseda Univ.)
ITO Ken fft J1i
ITO Tomoyuki fft Hi m~ ff (Sci. Eng. Res. Lab., Waseda Univ.)
IW ASA N aohito :E {tc ~ 1= (Dep. Phys., Rikkyo Univ.)
IZUMI Hideaki ill 7](
IY3 (Fac. Sci., Tokyo Inst. Technol.)~ ~ (Sch. Sci. Eng., Waseda Univ.)
KOBAYASI Misaki Ij\
KOGANEMARU Kenichi Ij\~A{§t- (Graduate Sch. N agatsuda, Tokyo Inst. Technol.)
KOMIYAMA Tatsuto ~ Lli ft A (Sch. Sci. Eng., Waseda Univ.)
KURA Jumpei ~~ lfZ (Fac. Sci., Tokyo Inst. Technol.)
KUROKA W A Meiko ~ JII 1Y3.y (Dep. Phys., Rikkyo Univ.)
KUWAHARA K6ta ~ @: 7Z.:* (Sch. Sci. Eng., Waseda Univ.)
LU Jun g~ (Inst. Phys., Univ. Tsukuba)
MATSUDA Kiyohide :f'.t EEl M(Fac. Sci., Tokyo Inst. Techno!.)MIYAMOTO Shouichi 15;$: BB ~ (Cyclotron and Radioisot. Cent., Tohoku Univ.)
MIZOI Yutaka
it ~ (ColI. Gen. Educ., Osaka Univ.)
MIZOT A Takeshi m EEl j\ it (Inst. Phys., Univ. Tsukuba)
MORIGUCHI Ako ~lfE.y (Japan Women's Univ.)
NAGANUMA Masayuki 7k ill lE fi (Graduate Sch. Nagatsuda, Tokyo Inst. Techno!.)NAGATA Kazuhiko :R EB *D 1ft (Fac. Sci., Tokyo Inst. Technol.)
NAKAI Yoichi r:p # ~ ~ (Dep. Phys., Kyoto Univ.)
NAKAMURA Takashi r:p *j ~ P] (Fac. Sci., Univ. Tokyo)
NISHIO Teiji 5 ~ :fii til (Dep. Phys., Rikkyo Univ.)
NUNOY A Yoshihiko ;fp ~ ~ 1ft (Dep. Phys., Rikkyo Univ.)
ODAHARA Atsuko Ij\EBmtJ!j[.y (Dep. Phys., Kyushu Univ.)
OHNISHI Hiroko
5 1ft.y (ColI. Agric. Vet. Med., Nihon Univ.)
OHNO Mariko "*f.f~J!I!-T (Radioisot. Cent., Univ. Tokyo)
OHSAKI Yoshinori~ ~(Graduate Sch. Nagatsuda, Tokyo Inst. Technol.)
OHTSU Hideaki~ (Fac. Sci., Univ. Tokyo)
OKADA Hiroyuki ffijj EB 7Z. Z (Sch. Sci. Eng., Waseda Univ.)
OKUNO Hiroki ~ f.f a; W (Fac. Sci., Univ. Tokyo)
PU Y. H. $~ r.Jf. (Inst. Phys., Univ. Tsukuba)
SAKAMOTO Naruhiko ~;$: pJG 1ft (Fac. Sci., Univ. Tokyo)
SATO Hiromi {tc Hi a; #ij (Fac. Sci., Tokyo Inst. Technol.)
SAWADA Shinya ~ EB ~ fu (Dep. Phys., Kyoto Univ.)
SEKI Hiroyuki 00
7.i. Z (Graduate Sch. Nagatsuda, Tokyo Inst. Technol.)

=

'*

m

***

*

m

°

"*
"* *c
"*?$ *-226-

SEKINE Takashi ~ fR
~ (Fac. Sci., Tokyo Inst. Technol.)
SHIMADA Kenji £ E8 {§t % (Fac. Sci., Tokyo Inst. Techno!.)SHIZUMA Toshiyuki f¥ ra~ {~1T (Dep. Phys., Kyushu Univ.)
SOSO Lucio (Fac. Sci., Tokyo Inst. Technol.)
SUEMATSU Shigeyuki
f'~ ~ 1T (Dep. Phys., Kyushu Univ.)
TAJIMA Yasuhisa E8 £ ~ 7... (Fac. Sci., Tokyo Inst. Techno!.)TAKEDA Kenji 1"1 E8 .R;t (Fac. Sci., Tokyo Inst. Technol.)
TERANISHI Takashi -# gg~(Fac. Sci., Univ. Tokyo)
TOMITA Shigeo ~ E8 pJ(; ~ (Inst. Phys., Univ. Tsukuba)
TOMURA Hiromi :>i- tJ ~ ~ (Dep. Phys., Kyushu Univ.)
UEDA Tomomi L E8 %I ~ (Japan Women's Univ.)
UENO Hideki J::!T 31§ W (Fac. Sci., Tokyo Inst. Techno!.)UESAKA Tomohiro J:::f& 1fi. ~ (Fac. Sci., Univ. Tokyo)
W AKA SA Tomotsugu ;:fi ~ ~ Ifflm (Fac. Sci., Univ. Tokyo)
YAJIMA Akira 9( ~~~ (Fac. Sci., Tokyo Inst. Technol.)
YAMAMOTO Takuhisa UJ
liJ 7... (Fac. Sci., Tokyo Inst. Techno!.)YAMAZAKI Hiroshi UJ ~ "5L ~Pj (Fac. Sci., Tokyo Inst. Technol.)
YASHIRO Yoshinori j:( 1~ • ~ (Fac. Sci., Tokyo Inst. Technol.)
YOON Chong Cheol jf
j i ~ (Fac. Sci., Tokyo Inst. Techno!.)YOSHIDA Hiroshi E E8 ~ I§j (Fac. Sci., Tokyo Inst. Techno!.)YOSHIDA Kenichiro EE8{§t-~~ (Dept. Phys., Kyoto Univ.)
YUASA-NAKAGA W A Keiko r:p}ll J!3: T (Inst. Phys., Univ. Tsukuba)
ZHAO Zhiping (Yale Univ., U.S.A.)**

Atomic Physics Laboratory=

ANDO Kozo !i ~ iU
KAMBARA Tadashi t$ ~1£
KRAVIS Scott (STA-fellow)
NISHIDA Masami gg E8 ft ~SHIMAMURA Isao £ N
F,.!{

AWAYA Yohko ~ ~ ~ T
KAN AI Yasuyuki jz it 1* Z
NAKAI Yoichi r:p it ~ OURA Masaki *- mi 1£ ~YOSHIDA Takashi E E8 ~ ;t*(Visitor)
AZUMA Toshiyuki{~1T (ColI. Arts Sci., Univ. Tokyo)
BERENYI Denes (ATOMKI, Hungary)
BHALLA Chander P. (Kansas State Univ., U. S. A.)DANJO Atsunori :f:I L ~ ~ (Dep. Phys., Niigata Univ.)
DePAOLA Brett D. (Kansas State Univ., U. S. A.)
FUJIMA Kazumi ~ ra~~ (Fac. Eng., Yamanashi Univ.)
FUKUDA Hiroshi 1M E87};. (Sch. Administration and Informatics, Univ. Shizuoka)
HARA Shunsuke ~{~ft (Dep. Gen. Educ., Tsukuba ColI. Technol.)
HARSTON Michael R. (Oxford Univ., England)
HINO Kenichi B!f {§t (Dep. Eng. Phys., Univ. Electro-Commun')~ (Sci. & Eng. Res. Lab. Waseda Univ.)
HITACHI Akira ,F3 t/j
ISHII Keishi E it It Z (Dep. Eng. Sci., Kyoto Univ.)
ISOZUMI Yasuhito .li+f~~A (Inst. Chern. Res., Kyoto Univ.)
ITO Shin W Hi
Jt (Radioisot. Res. Cent., Kyoto Univ.)
ITOH Akio W Hi f)c ~ (Fac. Eng., Kyoto Univ.)
ITOH Yoh W ~~ (Fac. Sci., Josai Univ.)
KARASHIMA Shosuke ~ ~ ~ ft (Dep. Electron. Eng., Tokyo Univ. Sci.)
KA W ATSURA Kiyoshi )II 00~ (Kyoto Inst. Technol.)
KOBAYASHI Nobuo IJ\ ~ ill ~ (Dep. Phys., Tokyo Metrop. Univ.)
KOHARA Takao IJ\ ~ ~ ~ (Fac. Sci., Himeji Inst. Techno!.)
KOIKE Fumihiro IJ\ ¥fu X 1W (Sch. Med., Kitasato Univ.)
KOIZUMI Tetsuo IJ\:J.R ~ ~ (Dep. Phys., Rikkyo Univ.)

-

-227-

KOMAKI Kenichiro IJ\~iiff-~~ (ColI. Arts Sci., Univ. Tokyo)
fJ! ~~ (Natl. Res. Inst. Police Sci.; ColI. Arts Sci., Univ. Tokyo)
KUROKI Kenro ~LENCINAS Sergio (Univ. Frankfurt, Germany)
MA TSUO Takashi f'~ ~(Dep. Pathol., Tokyo Med. Dent. Univ.)
MA TSUZA W A Michio f'~ ~ Jm ~ (Dep. Eng. Phys., Univ. Electro-Commun.)
MIT AMURA Tohru -=EBM ~ (Fac. Eng., Himeji Inst. Technol.)
MIZOGAW A Tatsumi m}ll IN 8 (Nagaoka ColI. Technol.)~ (Inst. Chern. Res., Kyoto Univ.)
MUKOYAMA Takeshi ~ LlJ
OHT ANI Shunsuke~ 1~ 1r (Inst. Laser Sci., Univ. Electro- Commun.)
OKUNO Kazuhiko ~ Jf fD 1$ (Dep. Phys., Tokyo Metrop. Univ.)
SA TO Hiroshi ~ Hi ~ ~ (Dep. Phys. Ochanomizu Univ.)
SCHMIDT - BOCKING Horst (Univ. Frankfurt, Germany)
SEKIOKA Tsuguhisa 00 ~ 1fflm:A (Fac. Eng., Himeji Inst. Technol.)
SHIBATA Hiromi ~ EB ffr ~ (Res. Cent. Nucl. Sci., Univ. Tokyo)*~ it (Tandem Accel. Cent., Univ. Tsukuba)
SHIMA Kunihiro ~SHIMAKURA Noriyuki ~ ~ *c. Z (Gen, Educ. Dep., Niigata Univ.)
SUZUKI Hirosi
1$ (Inst. Laser Sci., Univ. Electro-Commun.)
TAWARA Hiroyuki ~it Z (Natl. Inst. Fusion Sci.)TERASAW A Mititaka ~ ~ 1lffl # (Fac. Eng., Himeji Inst. Technol.)TOSHIMA Nobuyuki ? ~~ f§""$ (Inst. Appl. Phys., Univ. Tsukuba)(Fac. Technol., Tokyo Univ. Agric. Technol.)
TSURUBUCHI Seiji ~ mM ~W AKIY A Kazuyoshi ~ ~ - ~ (Dep. Phys., Sophia Univ.)
WATANABE Shinichi ill J2J.1~ (Dep. Eng. Phys., Univ. Electro-CommunJ
YAMAZAKI Yasunori LlJ dffiJ ~ m (ColI. Arts Sci., Univ. Tokyo)
YOSHINO Masuhiro E Jf ~"5b (Lab. Phys., Shibaura Inst. Technol.)ZOU Yarning ~~illZ f!Jj (Jiao Tong Univ., China)

*

*

"*

n*

=

(Students)(ColI. Arts Sci., Univ. Tokyo)
KAKUTANI Nobukazu fI3 ~ ~ KASUGA Masahito If: a _ A (ColI. Arts Sci., Univ. Tokyo)
KYOH Suigen ~Sffi fJi (Fac. Eng., Kyoto Univ.)
NAGATA Michi 7.k EB ~ ~ (Dep. Phys., Meisei Univ.)
NAKAMURA Nobuyuki r::p M ill 1:r (Inst. Laser Sci., Univ. Electro- Commun.)
NEGISHI Tomoo ;f,N i¥ ~ 7( (Dep. Phys., Sophia Univ.)
Itt (Dep. Phys., Rikkyo Univ.)
SANO Mutsumi ~ Jf
YAMAGATA Masahiro LlJ Jf3 I§ ~ (ColI. Arts Sci., Univ. Tokyo)
YAMASHIT A Tetsurou LlJ T ~ ~~ (Dep. Phys., Rikkyo Univ.)
Metal Physics Laboratory
ISHIDA Katsuhiko E EB 1m 1$
KOY AMA Akio IJ\ LlJ BB 1it
MA TSUSHIT A Akira f'~ T
f!Jj
N AGAMINE Kanetada 7.k ~ ~ ,'is',
YAGI Eiichi J\**-

KADONO Ryosuke r~ Jf ~ ~MA TSUNO Shun-ichi f'~!f 1~ MA TSUZAKI Teiichiro f'~lIffiJtJHfJ~~
W AT AN ABE Isao ill jf r)] 1it(Visitors)
AKAISHI Yoshinori tift. D ~ *c. (Fac. Sci., Hokkaido Univ.)
FUJIOKA Manabu Hi ~$ (Cyclotron Radioisot. Cent., Tohoku Univ.)
JONES E. Steven (Dep. Phys. and Astronomy, Brigham Young Univ., U.S.A.)
KAMIMURA Masayasu L MIT ~ (Fac. Sci., Kyushu Univ.)(Fac. Sci., Hokkaido Univ . )KUMAGAI Kenichi fl~ ~ fJ! MINAMISONO Tadanori 1¥I ~ ,'~ j'!1j (Fac. Sci., Osaka Univ.)
MIYAKE Yasuhiro -= ~ ~ it (Meson Sci. Lab., Univ. Tokyo)
MORITA Masato ~ EB IT A (Fac. Sci., Jyosai Univ.)-228-

TORIKAI Eiko ,~. IPk: -T (Fac. Eng., Yamanashi Univ.)tJ (ICU)
WATANABE Tsutomu ?1l $(Student)
STRASSER Partrick(Fac. Eng., Univ. Tokyo)

Magnetic Materials Laboratory

OKADA Takuya~ 83 .$ t!1

Plasma Physics Laboratory

OYAMA Hitoshi* UJ(Visitor)
SAKAMOTO Yuichi :f;&~

YANO Katsuki~!f 1m %* fit - (Electr. Eng. Dep., Toyo Univ.)

Microwave Physics Laboratory

MIN 0 H Arimichi~ liB 1£ j!!

Earth Science Laboratory

TAKEMATSU Noburu t'r r~f$

Semiconductor Laboratory

AOY AGI Yoshinobu 11 fPP R: ffi(Visitor)
AONO Keiko 11 Jf ;fi -T(ColI. Lib. Arts, Kitasato Univ.)

Inorganic Chemical Physics Laboratory

AMBE Shizuko 3i: $ D -T
MAEDA Kuniko iW 83 *13 -T
TAKAMI Michio rWJ ~ j!! ~if~
KA W AI Jun roJ.gMATSUO Yukari f'~~EEfifJj(Visitors)
ISHII Keizo 15 # • ~ (Cyclotron Radioisot. Cent., Tohoku Univ.)
SA SA Yoshihiko 16: J:( ~ J$ (Lab. Mater. Sci. Technol., Waseda Univ.)
UDA Masayuki f 83 J;j) Z (Dep. Mater. Sci. Eng., Waseda Univ.)(Students)
ISOMURA Tomoyuki f1;fj ~ Z (Dept. Mat. Sci. Eng., Waseda Univ.)
SUZUKI Setsuo ~~ ~ (Dept. Ind. Chern., Univ. Tokyo)
UDA Eiichirou f83~-fl~ (Dept. Mat. Sci. Eng., Waseda Univ.)*

Nuclear Chemistry Laboratory

AMBE Fumitoshi 3i: $ X ~5z
ITOH Yoshiko ftt
7J -T
KOBAYASHI Yoshio IJ\* ** •~

ARA T ANI Michi :m t}- ~ ~IWAMOTO Masako
IE -T
OHKUBO Yoshitaka *~f*~r'SJ

=* *

-229-

iWEB ~j: ~ iJ)

MAEDA Haruka(Visitors)
ASAI Kichizo 1! it E ~ (Univ. Electro- Commun.)
BABA Hiroshi ~ t~(Fac. Sci., Osaka Univ.)
CHEN Shaoyong ~~(South China Sea Inst. Oceanol., China)
FURUKAWA Michiaki r!I JII ~ sJ3 (Fac. Sci., Nagoya Univ.)
IMAI Masato 4- it .IE A (Komatsu Electronic Metals Co., Ltd.)HARAKAWA Hiroaki ~ JII ffr jj[ (ColI. Sci. and Eng., Aoyamagakuin Univ.)
KIMURA Kan
t1 ~ (ColI. Sci. and Eng., Aoyamagakuin Univ.)
KOJIMA Sadao IJ\ ~ ~:!J3 (Nucl. Med. Cent., Aichi Medical Univ.)
KUBO Michael Kenya :::z 1* ~ ili (Fac. Sci., Univ. Tokyo)
MINAI Yoshitaka ~ ~ {* ~ (Fac. Sci., Univ. Tokyo).MURAKAMI Hideoki t1 J:: ~ ~ (Tokyo Gakugei Univ.)
NOZAKI Tadashi IT!If{U.IE (Sch. of Hygienic Sci., Kitasato Univ.)
OKADA Shigenobu ~ EB ~ {§ (RID Eng., Shimazu Corp.)
OOHIRA Shigeo-¥ m:!J3 (Nikkei Techno!. Res. Co., Ltd.)SAITO Kazuo if ni ~D:!J3 (Toshiba Corp., R&D Cent.)
SAITO Tadashi li ni@: (Fac. Sci., Osaka Univ.)
SHIBATA Sadao ~ EB ~ 7( (N atl. Inst. Radiol. Sci.)SHIBATA Seiichi ~ EB ~ (Inst. Nucl. Study, Univ. Tokyo)
SHINOHARA Atsushi 1tl ~]I¥. (Fac. Sci., Nagoya Univ.)
SUGAI Isao ;:g it~ (Inst. Nucl. Study, Univ. Tokyo)
T AZAKI Kazue EB!If{U- ~D iI (Fac. Sci., Shimane Univ.)
TOMINAGA Takeshi ~ 7k
1J! (Fac. Sci., Univ. Tokyo)
Y AlTA Tsuyoshi ~ t&
~ (J apan Atomic Energy Res. Inst.)
YOKOTA Yuko • EB
T (ColI. Sci. and Eng., Aoyamagakuin Univ.)
YOKOYAMA Akihiko f1J Lli ~ ~ (Fac. Sci., Osaka Univ.)
YUKA W A Masae m}ll *E ~ (N atl. Inst. Radiol. Sci.)

*

m

*

*-

m

(Students)
AKIYAMA Hiroshi fj( Lli~ (Dep. Metal Eng., Shibaura Inst. Technol.)
BAMBA Takehiro
t~ ;t iW (CoIl. Sci. and Eng., Aoyamagakuin Univ.)
IDA Katsuyuki it EB MJ Z (Fac. Sci. & Eng., Tokyo Denki Univ.)
KAWARADA lun 1"aJ~EB i~ (ColI. Sci. and Eng., Aoyamagakuin Univ.)
KIRIU Masaru fIfIj ~(Fac. Sci., Osaka Univ.)
KURACHI Junji ~ ~ i*:t: (Fac. Sci., Nagoya Univ.)
MUROY AMA Toshiharu ~ Lli {~~ (Fac. Sci., Nagoya Univ.)
NAKAMURA Jin rp t1{= (Univ. Electro-Commun.)
OHTSUKA Hiroshi~ iW(Fac. Sci., Univ. Tokyo)
SHINTAI lunichirou ~*r~-.e~ (Fac. Sci., Nagoya Univ.)
TAKAHASHI Yoshio ~ ~ ~ 7( (Fac. Sci., Univ. Tokyo)
T AKESAKO Kazuhiro tt:iEl ~D ~ (Fac. Sci., Osaka Univ.)
TANAKA Shigeo EB rp No:!J3 (Fac. Sci., Toho Univ.)
TANIGUCHI Eugene ~ 0 ~ {= (Fac. Sci., Nagoya Univ.)
UMEMURA Yasushi
t1 ~:t: (Fac. Sci., Univ. Tokyo)
W A T AN ABE Seiya i1t ill ~ ili (Fac. Sci., Osaka U niv . )Y ANO Daisaku ~ IT
1'1= (Fac. Sci., Osaka Univ.)
YOSHINAGA Hiroshi E 7k*. (Dep. Metal Eng., Shibaura Inst. Technol.)

*

*

*

se

m

*

Chemical Dynamics Laboratory
KIMURA Kazuie* t1 -~(Visitor)-230-

ITO Yasuo W JJi ~ ~(Res. Cent. N uel. Sci. Technol., Univ. Tokyo)(Students)
MORITA Kazuo ~ 83 fD(Dept. Phys., Chuo Univ.)
NAKAMURA Seiji q:t;ft rg ~ (Dept. Phys., Chuo Univ.)
I!t m (Dept. Phys., Chuo Univ.)
NEMOTO Ryuji fla*Cellular Physiology Laboratory

HANAOKA Fumio 1E ItQl )( •YATAGAI Fumio ~B3~)(~KIT A YAMA Shigeru it Lli

ijl(Visitors)
ANDO Koichi ~ JJi ~ (N atl. Inst. Radiol. Sci.)
BAVERSTOCK Keith F. (Radiobiol. Unit, Med. Res. Counc., U.K.)
FUKUMURA Akifumi 1M;ft Iyj ~ (N atl. Inst. Radiol. Sci.)
FURUSAWA Yoshiya tt tR f~ iQ. (Natl. Inst. Radiol. Sci.)
HASHIMOTO Shozo ;fit~.=. (Fac. Med., Keio Univ.)
HOSHINO Kazuo £!f -1£ (Natl. Inst. Radiol. Sci.)IIZUKA Masayuki j& ~ lE Z (N atl. Inst. Radiol. Sci.)
ITOH Hiroko W J1j ~ T (Natl. lost. Radiol. Sci)
ITO Hisao W :!A ~ (Fac. Med., Keio Univ.)
KANAI Tatsuaki 31t: it jj Iyj (Natl. lost. Radiol. Sci.)
KA W ACHI Kiyomitsu iii] P3 rg JIG (N atl. Inst. Radiol. Sci.)
KAWASHIMA Katsuhiro }II ~ 1m 5[. (N atl. lost. Radiol. Sci.)
KIKUCHI Masahiro ~ JiB lE it (J apan Atomic Res. Inst., TakasakD
JC lE ~ (Natl. Inst. Radiol. Sci.)
KIMOTO Masafumi
KOBAYASHI Yasuhiko IJ\:# ~ ~ (Japan Atomic Energy Res. Inst.) .
KOHNO Toshiyuki iii]!f f3t Z (Natl. Inst. Radiol. Sci.)
KOIKE Sachiko IJ\ ng ¥ T (Natl. Inst. Radiol. Sci.)
KOJIMA Eiichi IJ\ Nb(Natl. lost. Radiol. Sci.)
KOSAKA Toshifumi IJ\:f:.& f3t)( (Dep. Vet. Radiol., Nihon Univ.)
83 .1I ~ (Fac. Med., Yokohama City Univ.)
KUBOTA Nobuo
McINTYRE Cindy L. (Radiobiol. Unit, Med. Res. Counc., U. K. )(Natl. lost. Radiol. Sci.)MINOHARA Shinichi • ~ f$ NAKAI Hirokazu q:t it 5[. fD (Dep. Agric., Shizuoka Univ.)
OHARA Hiroshi -)( ~5[. (Dep. Gen. Cul., Okayama Univ.)
SOGA Fuminori ~ fJt )( 'g (lnst. Nuel. Study, Univ. Tokyo)
SUDO Michio ~J1j~W1£ (N atl. Inst. Radiol. Sci.)
TAKATUJI Toshihiro ~ J± f3t 7Z. (RI Cent., Nagasaki Univ.)
TAN AKA Kaoru 83 q:t•(N atl. Inst. Radiol. Sci.)
TSUBOI Atsushi :PjZ it~ (N atl. Inst. Radiol. Sci.)
7Z. (Japan Atomic Energy Res. Inst.)
W A T AN ABE Hiroshi r1f ill
WATANABE Masami r1f illlE a (RI Cent., Fac. Med., Yokohama City Univ.)
YAMASHITA Shoji Lli ~ J§ <x (Natl. Saitama Hospital)

*

*

=*

*-

m

(Student)
SUZUKI Masao

~

=*

ft.

(RI Cent., Fac. Med., Yokohama City Univ.)

Safety Center

INAMURA Takashi fm;ft.$:
KAGA YA Satoru DOW!¥. ,tft
KA TOU Takeo DO J1j ft\ •MIYAGAWA Makoto '§ }II~:a

INOUE Yoshio it..t. ~ ~KA TOU Hiroko DO J1j it T
MA TSUZAWAY asuhide ;f'~ tR !fi
SAKAMOTO Ichiro ~
~~

*-

-231-

*

SHINOHARA Shigemi 1t¥ ~ [faUSUBA Isao if. ~~Surface Characterization Center*

KOBAYASHI Takane IJ\ 1*

IW AKI Masaya :E
IE ~SAKAIRI Hideo :1;& A ~.

tlI$Radioisotope Technology Division
NAKANO Kazushiro

r:p If fO ~YATAGAI Fumio~EBffit:X:~

Synchrotron Radiation Facility Design Group
ANDO Ainosuke ~*~Z.m
EGO Hiroyasu ~ ~ 11 Jt
HARA Masahiro ~ft ijLKAWASHIMA Yoshitaka JII lilJ t$ ~KUMAGAI Noritaka ~~ ~ ~ ~MATSUI Sakuo ;f'~#ftc~~
NAKAMURA Takeshi r:p M
tMJU
OHNISHI Jun-ichi 7\. i§ ~ OUCHI Tetsuya 7\. ~ ffi ili
SASAKI Shigeki {tel{ *[fW
T AKANO Shirou ~ If ~ ~~T AKESHIT A Isao t'r T ~ ~W ADA Takahiro fO EB ~ *WANG Yong x~
XU Choyin f~
fAm

BE Suck Hee ~-m ~FU JIWARA Shigeki J1j ~KAMITSUBO Hirornichi ~ ptz 7.i. ~KUMAGAI Keiko fl~ ~ ;f! T
MASUDA Takernasa ~ EB tMJU iE
MOTON AGA Shoshichi :lG 7.k ag -t
OHASHI Yuji 7\. ~ m
OIKAWA Yoshifurni ~ JII ~ :w
SAKA UE Hiroyuki :1;& ~ m
SOUTOME Kouichi lfl-Z:tc7'6T AKEBE Hideki fAt $ ~ W
TANAKA Hitoshi EB $t:J
W ADA Takeshi fO EB:b.t
WATANABE Kowashi ~ 31
tMJU

aw

=

(Visitors)
GOHSHI Yohichi ..g.;1S; ~ (Dept. Indust. Chern., Univ. Tokyo)
HANASAKA Takao 1£:1;& i¥: fit (Shimazu Co.)HA YAKAW A Shinjiro !f.}lI't.=~~ (Dept. Indust. Chern., Univ. Tokyo)
HIRANO Yoshiki ~ If 1.i W (Anelva Co . )INOUE Kouji tt: ~ ~ P] (Kobe Steel, Ltd.)SHIBUY A Keiichi ~ ~ il: (SMC Ltd.)TAKAHASHI Sunao ~ ~~ (Kobe Steel, Ltd.)TSUCHIY A Masao ± ~ ~ ~ (IHI Co.)YAN AGI Yoshihiko:fPIJ~ tffi (Hitachi, Ltd.)YOKOUCHI Shigeru~[f (Osaka Vacuum Ltd.)m(Students)(ColI. Hum. Sci., Nihon Univ)
IGARI Sin- ichi 1! 1'!if A KATO Haruhiko 110 J1jtffi (Fac. Eng. Sci., Chuo Univ){}t m (ColI. Hum. Sci., Nihon Univ)
SUGANUMA Kenji ;gmm-232 -zAUTHOR INDEXABE Kenichi IlcJfm{jl- 23~

ABE Ryo 1lcJ$

EKSTROM C.

3, 6

1lcJ$~~ABE Yasuhisa

rr D ~~

EGUCHI Kiyomi

104

124

FERRAGUT Alain 11, 12

29ADACHI Minoru JEJi: • 26
AIHARA Toshimitsu ~@:flj:7't 4

FRANCE III Ralph Hayward 19
FUCHI Yoshihide~J

AKAGI Hiroyasu $**3( 3,6

FUJIKI Kenichi

JJi*~-ALONSO J.R. 27
AMBE Fumitoshi 3($X~ 83,84,85,86,87,88,89,93,-

FUJIMA Kazumi ~Fa'-~ 80
FUJIMAKI Masaki ~~.IEW 15,21,23
FUJIOKA Manabu ~1lO.I $ 9

94,95,96
3($~TAMBE Shizuko

83, 84, 85, 86, 87, 88, 89, 95

ANDO Ainosuke 3(*~Z~ 147,151
ANDO Koichi 3(JJi~- 107,108
ANDO Kozo 3(~~U= 59,67
ANDO Yoshiaki 3(~~~ 19
AOI N ori W-#~

23, 113tIT* 17, 115
120~rR~;=t,

FUJISAWA Takashi

139

FUJITA Jirou ~EB=~B 138
FUJITA Shin ~EB ~ 183,184, 186
FUJITA Yoshitaka ~EBfE~ 9*

FUKUDA Hiroshi ~EB
77
FUKUDA Mitsunori ~EB:7'tJIWi 27

AONO Keiko W-!f:.f!T 74

FUKUDA Shigekazu~EBa -27

AOYAGI Yoshinobu 1f:MlR;fB" 74

FUKUDA Tomokazu~EB~fO

16,20

~#-~B

FURUKAWA Michiaki

ARAI Ichiro

16

mi::t-~~

ARATANI Michilr~AAA.

ARIMA Akito

97,132,133

50,51

ARUGA Takashi lrli' ~ 107,108
ASAHI Koichiro j@ fjj:-~B 20,26
ASAI Kichizo~#-=s~

71, 95, 96

ASAI Tatsuo ~#J.rR~ 109
AWAYA Yohko ~~;gT 59,60,61,62,64,65,66,67,~}II~£!lj~}II:m~FURUKAWA Shigeo

FURUT AKA Kazuyoshi

14,19, 75

GAl Moshe 19
GALONSKY Aaron 13
GALSTER Wilfried 13
GOHSHI Yohichi-§-;=t,~-127

AZUMA Toshiyuki
f~1T 66
BABA Hiroshi ~:I;f;90,91, 92
BAMBA Takehiro ;J::I;f;3tiW 88

GONO Yasuyuki

~.~Z

11,12

BE Suck Hee ~ Uig

161,162,163,164, 165, 167, 169,

HAHN Kevin I.

19

171,173

HAMA Hiroyuki

~

80

*
*

BEN Sei

GOTO Akira~~~

3,6,75,137,138,142

GUST AFSSON Morgen 124
IZ~

13

HANAOKA Fumio 1EllO.Ix1ii 104.IE 121~

13, 19, 75

9= J!~Z

FUTAMI Yasuyuki

108~~f01~~i::t-fB"1§j

FURUYA Shinji

91,92,93,94

CARJAN Nicolae 29

HANASAKA Takao 1E:t.&~1ii 163,167,169,171
HARA Masahiro @: ftsL 158, 159, 178, 179

CASADO J ase Antonio 45

HARA Shunsuke @:BENTZ Wolfgang 50,51, 52, 53~

CHAE Soo-Joh
CHEN S. Y.

~

~1'F

*?3~

11,12

HARAKAW A Hiroaki mtJ IlmJit 88

4,142

HASEBE Hiroo~i::t-$m1ii

HASEGAWA Masakoto

CHRISTIE William 24

HASHIZUME Akira
44, 45

DOKI Yasuhiro)g*/~'~±~G~iW

119, 120, 121
23,113

EGO Hiroyasu

~~iWx

~JT\

158, 159, 178, 179

176

AA , 135, 136!f-}IItJ!=~B

**

127

HAYASHI Takayoshi~~ 120HEMMI Masatake ~J!i!&j.\ 4, 141, 142
HEUSCH Bernard 14

DUONG Hong Tuan 124

119, 120~i::t-}llft§

HATANAKA Kichiji :l:II/!:f!-=sm 17,18,115,138
HAYAKAWA Shinjiro

DELBAR Thierry 19
DOKE Tadayoshi

HASEBE N obuyuki

95

4~i::t-$fB"1T

CHIBA Yoshiaki T~tIT£!lj 4,142
CHO Chul-Koo m tf&fL 107,108
DATE Schin #l"Jl f$

81

HARASAWA Kaoru mtrR •86

T~flj~CHIBA Toshiya

f~fI

HINO Kenichi

B !f{jl- 78, 79

HIRANO Yoshiki lfljfjjfjf 163

JEONG Sun-Chan~

HIRA T A Daisy 25, 48, 49]IN Wei-Guo 3ll:

f4j~.ltil~HIRENZAKI Satoru

1if 59,121

fj l±lHITACHI Akira

mIS, 21, 28, 46, 47

HOFMANN Helmut 33
HONMA Takayuki *ra'~Z 3,6
HORIGUCHI Takayoshi #WO~$!. 123
HOSAKA Masahito

f*~:p:f A

ICHIHARA Takashi

mw- ~ 17,18,113,114,115m}l[~=ICHIKAWA Ryuji

ICHIKAWA ShinichimJII~-

IEKI K~zuo *~fD~

10

11,12

13,14

j&~lEZIIZUKA Masayuki

KA Wei-Jei :f1iJ f~~ 105
KADONO Ryosuke r,jf $!.~ 72
KAGAYA Satoru

ffi 182

1Jo~~

~UJ

KAGEYAMA Tadashi

IT 3,6,137

KAIHO Kunio #if*n~ 132
KAMBARA Tadashi t$lJA lE 59, 60, 61, 62, 64, 65, 66,
J:.t~71-{~-

KAMIGAITO Osamu

107,108

IKEDA Kiyomi

1t!!83m~

35,36,39,40,41,42,43

IKEDA Nobuo

1t!!83{$~

9

~

75

KASAGI Jirohta :31:*ma~* 13
KASE Masayuki 1JDifJj~Z 3,4,6,75,121,137,138,142,
144
KASHIW AGI Toshisuke :f8*fUjf- 119,120tl£J:7"L='-J 138, 184

JtUJ-a~KATAYAMA Ichiro

IKEZAWA EijitI£~~=

4

KA TO Chihiro

IMAI Takashi

4-#

122

KA TO Hiroshi 1JoB 1ll 122~

3,6

KANAI Tatsuaki 3ll:#Jlf!Ij 104,105,106,107,108,111
KAN AI Yasuyuki 3ll:#f*z 59, 62, 64, 65, 66
KANNO Tooru rgjf

#m..- 111

IKEGAMI Kumio

123

JUNCAR Patrick 124

67,80

IIMURA Hideki j&:f.t~*c 10
IJIRI Kenichi

14

3,6

#-¥-o*mIDEGUCHI Eiji

17~~

1JO§T~

9122

INABE Naohito liEbZlr.16A 15,19,21,22,23,26,75,138
INAMURA Takashi fiIH'.t .$: 9,10,123,124,181,182,
184,186

KATO Hirotoshi 1JoHii11i5!: 107,108
KA TO Kiyoshi 1Jo§~7j 36
KATO Masayuki 1JoHi~z 52

INOUE Kouji ;ttJ:mRJ

KA TO Seigo

158,159,178,179

1JDiJ~.g:17

ISHIBASHI Mie E~~~ 89
ISHIDA Katsuhiko E83}}9j~ 68
ISHIDA Nobumichi E83f$~ 121

KA TOU Hiroko 1Jo§1Wr 182
KA TOU Takeo 1JoB~!t 182

ISHIDA Satoru 1583 ffi

KATSURAGAWA Hidetsugu

ISHIHARA Masayasu

17,18

ElJAlE~KATORI Kenji}jIlrl&~=

7OJ~

t~

21,23

ttJII~1fflIiJ

13,17, 19,20,22,23,

KAWAI Jun

24,26

KAWAMA Tetsuo mFa'trf!t 3,6,144
KAWASHIMA Hideo }ll~~!t 17,115

ISHIHARA Takeshi ElJA :lEt 77

69,123

125,127,129,130,131

ISHII N oriyoshi

E#~~

53

KAWASHIMA Yoshitaka JII ~~~ 158, 159, 178, 179

ISHII Takayuki

E#~$

75

KAWATSURA Kiyoshi }lIm

ISHII Yasuyuki E:j:j:f*1T 149
ISHIZUKA Takeo

E~:lEt'-J

123

ISOMURA Tomoyuki fI:f.t~z 131
ISSHIKI Hiroshi -tg 1ll 3, 6
ITO Hisao ffI"*~~ 105
ITO Tomoyuki ffI"§IDHT 120, 121
ITOH Yoshiko ffI"*jj-r
IT SUM I Kenji
IWAKI Masaya~~]1:1::E*lE~IWAMOTO Masako

KIKUCHI Masahiro~.t~lE1ll

103

KIM Hee J. 20
KIM J ong Chan 3ll: jjif 11, 12, 21
KIM Yong Kyun 3ll:

~~

21

98,99

KIMOTO Masashi *5CIT1: 107,108
KIMURA Kan *:f.t ~ 887,74

:E~lE-r

KIMURA Kazuie*M-~20, 101, 102

83,84,85,86,87,88,89,

KIMURA Mineo~:f.t*~79

181

KINOSHITA Akira

98,99

IZUMI Hideaki tfj*~~JENSEN Aksel S. 33

KIDERA Masanori *~ lEll 12
KIKUCHI Jun ~tI£ JIIW 119,120

119, 120IWASA Naohito :E1tCiElt: 19,23,24,38
IWATA Ren :E83 •

m: 66

20,26

KIRIU Masaru :ffI!J~
KITAGAWA Atsushi*-r w 98*- 90~t) II¥J($

27

KIT AJIMA Yoshinori ~t~~~ 127
KIT AO Kensuke :m:~ ~]f-WJ 135, 136

KITAYAMA Hiroki~tLIJ.ttg~

16

MATSUI Sakuo t'kJ:t:ftC-!Ax

153, 154, 156, 157

KIT AYAMA Shigeru~t LIJ

103, 109

MA TSUKI Seishi t'l*1lE~

123, 124~~t~Jt -KIT AZAW A Siniti

64

MATSUO Keiichi t'~~~- 176*P'1;f:~

KIUCHI Takashi

ti5- 183, 184, 186t'~*

MATSUMOTO Hiroshi

KITCHING Peter 16
107,108

MA TSUO Takashi t'l~

*

63

~

7, 181

MATSUO Yukari t'l~El:tMflJ

70

15, 16,21,22,23,24,25

MA TSUSE Takehiro t'lil3tti5- .14

KOBAYASHI Takane Ij\#

Ij\#f~$KOBAYASHI Toshio

IJ\#~~KOBAYASHI Yasuhiko

KOBAYASHI Yoshio Ij\#~~109

l'!f.J

72

83,84,85,86,87,88,

MA TSUTA Kensaku t'~37{1m 24, 27

89,95,96

MA TSUYAMA Hideto t'~LIJ B tf:lA 16
MATSUZAKI Masayuki t'~~J§z 10

KODAMA Masakado Yr..3i~F~ 13
KOHAMA Akihisa IJ\~#:9C 54
KOHARA Shigeo IN~.m:~t'~ ~MA TSUSHITA Akira

MATSUZAKI Teiichiro t'~dHff~m!l~68

MA TSUZAW A Michio t'~~Jm~ 79

142m

KOHNO Isao f!tJ!f181
KOHNO Tsuyoshi f!tJ!f ~ 75,119, 120,122

MA TSUZAWAY asuhide t'l¥R~* 182
MIN Byong 100 ~ pg~ 11,12

KOIKE Sachiko IJ\tt!!*-r-

107,108MINAI Yoshitaka

KOIZUMI Mitsuo IJ\JR:Yt1:.

123

IJ\~~~

KOJIMA Sadao

IJ\t;clVf-!l~

KOMATSU Haruko

IJ\t'~B!-r-

KRA VIS Scott D.

59,60,61,62, 65

66

138

MIY A TAKE Hiroari~

MIYAZAWA Yoshitoshi

9,17,115N~1§.*fD

N~1§.~-r-

KUMAGAI Makoto

N~1§.

154, 156, 157~~7J~

145,149,154,155,157

93,94~JIIl'!f.J-r-

KUROKAWA Meiko

KUROKI Kenro ~*{I!l~21,63,101,141

ffi 74N~1§.~;f:

KUMAGAI N oritaka'§ft\~-lli

9,118

66

KUSAKARI Hideshige

1j[)(IJ~*

10, 11, 12

KUSAWAKE Hiroaki

J}I~:B-*J§

91

9, 26

,§¥Rf~~~mM

MIZOBUCHI Akira
75

182,§*Bfj- 17, 115

MIYAMOTO Shouichi

KUDO Hisaaki IBi-!ABfj 9
KUMAGAI Keiko133

MIYAGAWA Makoto '§JlIJt§"

KUBOTA Masashi -!A1*EElE;E; 69

KUMAGAI Hidekazu

11, 12'§tiB1\~

13,15,19,20,21,22,23,26,

KUBOYAMA Satoshi -!A*LIJ~~

KURACHI lunji~-'¥~;t;!l~MITARAI Shiro

KUBO M. Kenya -!A1*~~ 89

KUBONO Shigeru -!A1*!f139

MINOHARA Shinichi l'lW-f$- 111

MIY ACHI Mutsumi-!A1*~*

24,27

MINOWA Tatsuya ~$iUJi~ 69

69

27

KUBO Toshiyuki

89~Eitl:ff~

MINOH Arimichi

93,94

KOMAKI Kenichiro

KREBS G.F.

~~f~;f:

MINAMISONO Tadanori i¥jIllJiSUW

l'!f.J

4,141,14230

ti5- 20
MIZOTA Takeshi r1JjEEft\;E; 14MIZOI Yutaka~#

BEEftC~x

MOMOTA Sadao

27

MOON Chang-Bum X

J§$B 21MORIKAWA Tsuneyasu~Jllt§:~MORITA Kazuo

10,11,12~EEfD$

101,1029, 11,12,118, 123

MORITA Kosuke~EEti5-fr

MORIY A Hitoshi~

MOTOBA Toshio

5G~~$

m ~ 119, 120
41*#

MOTOBA YASHI Tohru
J! 9, 19, 118
MOTONAGA Shoshichi 5G7kBfjt 154,157

KUWAHARA Kota ~W-*j,::: 116

MUNAKATA Kazuoki

*~-~

122

LEE Sang Mu
LENCINAS S.

MURAKAMI Hideokit.Lt~~

98,99* f§Jt14

MURAKAMI Hiroyuki tLtti5-z 9,119,120

62

LIEVENS Peter 124

MURAKAMI Takeshi ;ft.L {I 11,12

LINDG REN I.

MURA YAMA Toshiyuki ;ftLIJflJ* 123,124124

iW83 tj: ~ iJ~ 70,85,87,88,89
MAEDA Kuniko iW83:m-r- 16,125,127,130,131

NAGAE Tomofumi

MAlE Takeshi
MASUDA Kimiaki

NAGAMINE Kanetada

MAEDA Haruka_*ft\±

3,6~EE0BA

MASUDA Takemasa

121~EE~UlE

MATSUDA Sumio t'~83~~ 75

174

NAGAI Yasuki

7krr~x

7k#~W

NAGASAKA Yasushi
NAGASE Mamoru

1697k.~,~~:I:.&m~~i'i~

NAGATA Katsuaki 7k83J]Jl'!f.J

68,72
16

79
119,120

ltOJ*t1i=

NAGATA Michi

7J<EE~~

64

OKAMOTO Shinji

NAITOH Yohko

10J~i'$-f-

80

OKAMURA Hiroyuki

NAKAGAWA Takahide$JII~*

NAKAHARA Hiromichi$W-51J!! 9$#5k~DNAKAI Hirokazu$#~-

NAKAI Yoichi

59,60,61,67~W-~~ZISORIHARA Hikonojo

75

OSET Eulogio 46

27

NAKAJIMA Mitsuo

$~JEx

11,12

OSHIMA Masumi

NAKAJIMA Shunji$~~=

183,184

OTSU Hideaki *i$*1!l 18~

NAKAMOTO Atsushi$*

NAKAMURA Ichiro$Mm~~

119, 120
123$ Mffiff 64$M?I;E'; 101,102*~Jtm:OZAWA Akira /j\¥R mi 27

NAKAMURA Takashi$M~~

NAKAMURA Takeshi$M OOU 160,174

PELLARIN M.

124

NAKANISHI Noriyoshi$Iffi*c~

PENSELIN S.

124

PERSSON J.

124$!!!f~~NAKANO Kazushiro

103,104, 1Q6

NEGISHI Tomoo;f.&~~x64

NEMOTO Ryuji;f.&*~m

101, 102

NEUGART R.

124

10, 11, 12/N:P~i$JEJt

OY AIZU Michihiro

NAKAMURA Seiji

183,184,186

PINARD Jacques 124
PROKHV ATILOV M. A.

¥m

~JJE

16

14

:Zrr"ilT 121

NIEVES Juan 46

QU Yun He Jffi

NIIOKA Yuzo ffltOJ~= 169,171

RAGNARSSON Ingemar 124

NIIZEKI Takashi ff~
NILSSON Thomas 124~

17, 18, 115

RASIN V.1. 16
REDI Olav 124

NISHIGUCHI Iku IffiD

1m

105

RING Peter 49

NISHINAKA Ichiro g§$-fQ3 9
IffiLlJ~~

NODA Shuji!!!fEE1~~ROWNTREE David 16
SAGAWA Hiroyuki ftr:J115k"¥ 48
SAITO Tadashi %iH* ®: 90,91,92,93,94

72

132
~

NODA Yutaka !!!fEE

SAITO Yuko %iH*f§-f- 88

87

NOJIRI Yoichi !!!f5Ei'$- 27
NOMURA Izumi!!!fM~DJR

SAKAI Hideyuki

l@#~1T

SAKAMOTO Ichiro

16,20

18, 138:f:R*-~~

181,182:f:R*RX~NOMURA Toru !!!fM Jjf 9,118,124

SAKAMOTO Naruhiko

ODAHARA Atsuko /j\EELKlJ-f- 11,12

SAKAMOTO Shinichi :f:R:7CJt -OGAWA Masao

Ij\JII~~:f:RLf§~

SAKAUE Hiroyuki

11,12

*~f§=

173

158,159,178,179

OHKI Tomonori **~J{iJ · 4
OHKUBO Yoshitaka *)"1*~~ 83,84,85,86,87,88,
89,90,91,92,93,94,*

17,18,138
68

161,162, 163, 164, 165,

OGIWARA Kiyoshi ¥J<.W- if 139
OHASHI Yuji

97

pALINKAs J 6zsef 60

PUY.H.

NISHIYAMA Kusuo

17

OTSUKA Shozo *~~= 3,6
OURA Masaki *imIEWJ 59,60,61,62,65,66,67

NAKAMURA Nobuyuki

20,22,23,24,26

17, 18, 138

OKUNO Hiroki ~!!!fJtWJ 20,23,26
OLSON Douglas 24
OMAT A Kazuo Ij"f!jUDx

109$~Jt.A

NAKAJIMA Masato

3,6,14,15,75,137

184, 186

ItOJM5k~95,135

OHKURA Hiroshi *11"41
OHNISHI Jun- ichi *g-gk:lt!- 154,155,157*ill

SAKURAI Mikiot¥(:tt~x13

SANO (MURAOKA) Mitsuo~!!!fJlG~

SATO Hiromi ftr:H*Jt#ll 26
SA TO Hiroshi ftr:H* YfE. 30, 31, 32
SA TO Hiroshi ~H*t5!i::. 81
SCHMIDT-BOCKING Horst 62
SEKI Ryoichi

~

~-

54

OHNUMA Hajime
ffi 17,18,115
OHTA Shigemi ~EE~~ 58

SEKIMOTO Michiko ~*~~-f- 16
SEKINE Takashi ~;f.& ~ 20,26

OHTANI Shunsuke *i:H3tfl'" 64

SHIBATA Sadao~EE~x

87,88,89*:PJZ ~ 27

SHIBATA Seiichi~EE~-

93,94,95

SHIBUYA Keiichi~1:j.1i&-

161, 162

OHTSUBO Takashi

OHY A Jiro **~~B 75
OKADA Takuya ItOJEE..$:iB 71,95,96
OKAMOTO Hiroyuki

1tOJ*1i1T 79

SHIKA T A Takashi[9:1J~!i::.

SHIMIZU Wakako ?l7l<biJ)-f-

183
107,10837

SHIMODA Tadashi rB3

IE 9,26

SHIMOMURA Koichiro rt1~-~~123

SHIMOURA Susumu

rOO

!j:

SHINO Tomoaki fi~~

119, 120

15, 20, 21, 22, 23, 24, 25

W 91,92,93,94
SHINOZUKA Tsutomu fi~ *1J 9,123

SHIN OHARA Atsushi fi@:mWa'13N'r 11,12

SHIZUMA Toshiyuki

B3C:P~tQ.

TANAKA Kinya

183,186

TANAKA Masahiko

B3C:Pft~

17,115TANIGUCHI Eugene· ~D~t90,92,93,94

TANIKAWA Masashi~)IIMj~1§JIH~:1«

TANIHATA Isao

9,20

15,21,22,23,24,25,27,28,
49~

T ATSUMI Toshitaka~~

57~ -Mz 63
B3dfflJmiI 132, 133

SIEMSSEN Rolf 22

TAWARA Hiroyuki

SOUTOME Kouichi !f.z.ftJl[;- 37

T AZAKI Kazue

STROKE H. Henry 124

TENDOW Yoshihiko

7(J!!jJ~

135,136TERANISHI Takashi~iffi

23, 24SUDA Toshimi~enlJ~

16

iWb

SUEKI Keisuke **~1J- 9

TERASAW A Mititaka ~~{jffi~ 62

SUGAI Isao ;g# IQ 97, 123

TIBA Tokiko;g¥B~:1«

SUGANUMA Hideo

55, 56, 57

SUGAW ARA Masahiko ;gmt ~~10, 11, 12

T~ t ~.:r133

TOHY AMA Mitsuru iiLlJ ?/liII 34
TOKI Hiroshi ±~ -M 25,28, 46, 47, 48, 49~ 7k

SUGIMOTO Kenzo t3:2fs::{1= 24, 25, 27

TOMIN AGA Takeshi

SUGINO Shuji t3ff~~

119,120

TOMIZAWA Kazuyuki ~¥RfDZ

16

SUGITA Tadashi t3B3

0- 107,108

TOMOTANI Ariyoshi~:frtEffit

10

89

{I

SUMIYOSHI Hiroyuki 13:-aJhfT 44

TONUMA Tadao p¥BIERt 63,67

SUMIYOSHI Kohsuke {3:-aJl[;1J- 48

TOSHIMA N obuyuki

SUNAOSHI Hitoshi ;WY¥fl t

TOYODA Sakae :aB3
TOYOKAWA Hidenori

9

SUZUKI J:Iiromitsu ~*1tJl[; 158, 159, 178, 179

p~~ffi$*7689:a)lI~IDII±m~:1«

17,18

SUZUKI Hirosi ~* 1$ 64

TSUCHIY A Masao

SUZUKI Keiji ~*~~ 106
SUZUKI Masao ~*ftRt 106

TSUKADA Kazuaki ~B3fDIY3 9
TSUKIORI N oritoshi F.J Ji511{~ 3,6 ·SUZUKI Masayo~*~t!tSUZUKI Setsuo ~*m~SUZUKI Takeshi~*

SYMONS T.J .M.

27

UCHIKURA Akiko

127

UDA Eiichirou ~B3~-~~

15,21, 23

B3 ~~~ 17, 18

TAKAGI Tetsuya

r.1li~m:i.t!

TAKAHASHI Katsuhiko

UESAKA Tomohiro

129
129,131

20,26

J:.:I;5t~1$

3,6

URAl Teruo 00#.:1«

7,127

TAKAHASHI Miho r.1lim~* 43

VIALLE Jean-Louis 124

TAKAHASHI N oriaki r.1li~*1Y3 26
TAKAHASHI Tan r.1lim El 103,104,109,110,111,

VICENTE-VACAS Manolo J.

116,121r.1li~a:1«

89
TAKAKU Shinsaku r.1li~?i{'F 17,115
T AKAMI Michio ~~J!!~ 70,123,131
TAKA YANAGI Toshinobu r.1lilPlJ{~J!II 64
T AKEBE Hideki i1t$~W 154, 157, 174, 176
TAKEMATSU Noburu t'Jf'~ {$ 89
TAKAHASHI Yoshio

TAKENO Shiro t'Jff~~~ 95
T AKESAKO Kazuhiro t'JjgnD~ 91,92,93, 94
TAKESHITA Isaot'Jr~:1«

153,158,159,178,179

B3t1r.1li$ 75
B3C:P i$J 145,147,149,151
TANAKA Kazuhiro B3C:PmJJ: 50,51,52

TAMURA Takashi

18,138UESUGI Masato J:.t3IEA 75

184

r.1li~51~

J:.ff~W

10

UENO Sachiko J:.ffW.:r 16

123

T AJIMA Yasuhisa~B3J;tZ

UDA Masayuki
UENO Hideki

B3~~;a;:T AGISHI Yoshihiro

P'J~IY3.:r103,111,116,121{I

161, 173

46

WADA Michiharu fDEEJ!!tE1 9
WADA Takahiro

fDEE~;a;:29,174W AKASA Tomotsugu ;S:~~m 18;s:t3~~W AKASUGI Masanori
W AKI Koichiro~

W AKIY A Kazuyoshi*If:-~~

123

16~:fr-~

64

WATANABE Hiroshi tflJl1 ;a;: 103,109
WATANABE Kowashi

IP!IU 161,162,163,164,

tfl~

165,167,169,171,173
WATANABE Masami tflJl1IEB
W AT AN ABE Seiya

tflJl1~i.t!

WATANABE Yasushi tflJl1

106

92
~

15,20,22,23,24,68,
113,114TANAKA Hitoshi

W AT ARI Kazuo tflflJ-:1« 87

:frEB~X~

WIEMAN Howard H.

24

YATAGAI Furnio

XU Chao Yin ft

173

YA TOU Osarnu 9:2M

~~

)\**-

YAGI Eiichi
7,73
YAlTA Tsuyoshi ~flit ~ 88
YAMADA Taiichi UJEB~- 39,40,42
YAMAJI Shuhei

UJJm~.lJl

YAMAMOTO Takuhisa

17,115

YAMAMOTO Yasuo UJ*~~ 43
YAMASHITA Shoji UJr Jl§?X 105
YAMAZAKI Toshirnitsum 110

9:2~~-

52,53,54

YOKOUCHI Shigeru .f1iP"l N. 161,162,163,164,165,
167,169,171
YOKOYAMA Akihiko33, 37UJ*~~

YAZAKI Koichi

104,105,106,107,108

YOKOYAMA Ichiro.f1iUJEY3~~UJ -~~

90,91
144

YONEHARA Hiroto *W-~A 158,159,178,179
YOSHIDA Atsushi EEE ¥J( 9,11,12,20,23,26,113,

UJ~~JIt

114,118, 123, 135

47

YAMAZAKI Yasunori UJ~~m 66
YANAGI Yoshihiko ;fW ~~ 161

YOSHIDA Koichi

EEBJ'[;-

13,24,27

YANAGIMACHI Tornoki ;fWWTMW 119,120

YOSOI Masaru --9-~# ~ 17,18
YUASA- NAKAGAWA Keiko ~~(q:tJII)~T 14

YANO Katsuki 9;2JfMIW

ZHANG Yu-Hu

YANO Yasushige

163

9:2Jf~mYANOKURA Minoru 9:2ff1t

3,6,75,137,138~

4,83,84,85,87,88,
89,97,132,181

ZOU Yarningg~]idE 11,12
ill[EY3 59,60,61,65,67,80~

RIKEN Accelerator Progress Report!l1t~iff~PJT1JllilH~~.1S~n

~

~26~

(1992)'¥nx: 51f- (993) 3 J'! 23 B
fr f nx: 51f- (993) 3 J'! 31 B.!jil]

JHr~

l.f 1t ~ :pJf ~ JiJf{t~~
T351 - 01

/J\
±~:E

'if!~t*Iii~ ~(048) 462- 1 1 1 1

l.f1t~:pJf~ JiJf1Jn:i! ~:pJf ~;&(§ ~JI-g~~1t~n.lill]jiJf

f.t

B3

mfD -Jt mJ1\ if{ 2 :3} 1 -%**1m ~ ~n A"ilIJ:r\ 1t 11
T1l2 **tB~*I~>J';SJlll T 13 3 :3} 7 -%~ filii 5, OOOfIl

wnUjiJJIj}

理化学研究所
埼玉県

和光市

広沢