JAEA-Review
2010-056

JAEA-Tokai Tandem Annual Report 2009
April 1, 2009 – March 31, 2010
Department of Research Reactor and Tandem Accelerator

Nuclear Science Research InstituteTokai Research and Development Center

December 2010
Japan Atomic Energy Agency

日本原子力研究開発機構

JAEA-Review 2010-056

JAEA-Tokai Tandem Annual Report 2009
April 1, 2009 – March 31, 2010
Department of Research Reactor and Tandem Accelerator
Nuclear Science Research InstituteTokai Research and Development Center
Japan Atomic Energy Agency
Tokai-mura, Naka-gun, Ibaraki-ken(Received September 27, 2010)
The JAEA-Tokai tandem accelerator complex has been used in various research fields
such as nuclear science and material science by researchers not only of JAEA but also fromuniversities, research institutes and industrial companies. This annual report covers
developments of accelerators and research activities carried out using the tandem accelerator,
superconducting booster, and radioactive nuclear beam accelerator, from April 1, 2009 to
March

31,

2010.

Fifty-sevensummaryreports

werecategorized

into

seven

research/development fields:(1) accelerator operation and development(2) nuclear structure(3) nuclear reaction(4) nuclear chemistry(5) nuclear theory(6) atomic physics and solid state physics(7) radiation effects in materials.
This report also lists publications, meetings, personnel, committee members, cooperative
researches and common use programs.

Keywords : JAEA-Tokai Tandem Accelerator, Operation Results, Nuclear Structure, Nuclear
Reaction, Nuclear Chemistry, Nuclear Theory, Atomic Physics, Solid State Physics,
Radiation Effects in Materials, Progress Report.

Editors: Makoto MATSUDA, Satoshi CHIBA, Norito ISHIKAWA, Shin-ichi MITSUOKA,
Yosuke TOH, Kazuaki TSUKADA and Suehiro TAKEUCHIi

JAEA-Review 2010-056

原子力機構東海タンデム加速器 2009 年度年次報告

日本原子力研究開発機構
東海研究開発センター原子力科学研究所
研究炉加速器管理部（2010 年 9 月 27 日受理）

原子力機構東海タンデム加速器施設は、原子核科学や物質科学などの様々な分野において、原子力機構を始めとして、大学や公立研究機関、民間企業に利用されている。本年次報告書は、タ
ンデム加速器、ブースター加速器、放射性核種加速装置を利用し、2009 年４月１日から 2010 年 3
月 31 日までの期間に実施された研究活動の英文要約をまとめたものである。総数 57 件の要約を
下記の７部門に分類した。
（１）加速器の運転状況と開発（２）原子核構造（３）原子核反応（４）核化学（５）原子核理論（６）原子物理及び固体物理（７）材料の照射効果
また、発表論文と会議での口頭発表、タンデム加速器に関与した職員、タンデム加速器専門部会
委員、大学等との共同研究課題、及び施設共用課題のリストを掲載した。

原子力科学研究所：〒319-1195 茨城県那珂郡東海村白方白根 2-4
編集者：松田
竹内

誠、千葉

敏、石川

法人、光岡

末広

ii

真一、藤

暢輔、塚田

和明、

JAEA-Review 2010-056

Foreword
This report covers research and development activities with the tandem accelerator, its superconducting
booster and TRIAC radioactive ion accelerator at JAEA Tokai, for the period of FY 2008 (April 1, 2009 to
March 31, 2010). During this period, the tandem accelerator was operated over a total of 172 days anddelivered 25 different ion beams to the experiments in the fields of nuclear physics, nuclear chemistry,
atomic physics, solid state physics and radiation effects in materials. Thirty-six research programs werecarried out in collaboration with a total of about 250 researchers from universities and research institutes.
The TRIAC accelerator was operated for 26 days. The following are some of the highlights in FY 2009.
In the development of the tandem accelerator and the booster, an intense boron beam of 1 particle A was
supplied to experiments. A molecular beam of CO2+ was accelerated from the in-terminal ECR ion source.
The average acceleration field gradient all over the 40 superconducting resonators was recovered to 4.4
MV/m as a result of applying high-pressure water-jet rinsing to 28 resonators. Ion-beam analysis of RBS
method using a Ne beam was demonstrated to have high mass resolution.
In the development of TRIAC, a beam bunching system consisting of a pseudo saw-tooth wave
pre-buncher and a multi-layer chopper has been developed to provide an intense stable pulsed beam with awidth of less than 10 ns in a repetition rate of 2 MHz. The purity of radioactive 142Ba beams of 1.1 MeV/u
were investigated so that the experiment of the Coulomb excitation of 142Ba was found to be feasible.
In research of nuclear structure, B(E2) and Qβvalues of neutron-rich Eu isotopes were measured using the
ISOL with a surface ionization source equipped with UC target. The energies of the first 2+ states inneutron-deficient Pu and Cm nuclei, measured by α-ray spectroscopy, suggest that deformations of these
nuclei decrease towards N=126. In-beam γ-ray spectroscopy experiment of 173W using GEMINI-II shows
low-spin signature inversion associated with strong configuration mixing. A new technique of laser
spectroscopy for radioactive isotopes in the rhenium region has been developed. A candidate of a halo
analog state of 11Li was searched in 11Be, using a 9Li beam accelerated by TRIAC.
In research of nuclear reactions, excitation functions of fusion-fission cross sections in the reactions of
34,36

S + 204,206,208Pb were measured around the Coulomb barrier. Fusion enhancement at sub-barrier energies

in the 34S projectile reactions was larger than in the 36S cases. Fission following nuclear transfer in the 238U
(18O, 16O) reaction was studied as a surrogate for the 239U(n, f) reaction. The obtained fission barrier heightof the compound nucleus 240U agreed with that determined in the (t, p) reaction.
In research of nuclear chemistry, the cation exchange behavior of rutherfordium, 104Rf, together with its
homologues Zr and Hf in H2SO4/HNO3 mixed solution has been investigated. The result clearly
demonstrates that the sulfate complex formation of Rf is much weaker than that of Zr and Hf. The
successful reduction of mendelevium from Md3+ to Md2+ using an electrochemistry apparatus is presented.
In the field of nuclear theory, researches to support a surrogate method were carried out. A general criterioniii

JAEA-Review 2010-056

that validates the surrogate ratio method was found. A Dubna’s "unified model" was applied to reactions
between 18O and 236, 238U, and validity of the above criterion was confirmed. Shell structure of oxygenisotopes, which will serve as projectiles in the surrogate method, were also investigated. A new formulation
to evaluate incomplete and complete fusion was carried out with CDCC theory, and a global trend ofcompetition between allowed and first-forbidden transitions relevant to the r-process nucleosynthesis wasfound.
In research of atomic physics and solid state physics, charge state distributions were measured forpenetrations of 2 MeV/u S6+ to S16+ ions through C-foil targets of 0.9 - 200 μg/cm2 in thickness, and asimulation of the distributions was performed. Li diffusion coefficients were measured for LiI and LiGa
ionic conductors of NaTl-type inter-metallic compounds and La2/3-xLi3xTiO3 perovskite-type lithium ion
conductor.
In research of radiation effects in materials, an elongation of ion-irradiated Zn nano-particles embedded in
SiO2 was clearly observed even at relatively low fluence by using the linearly-polarized optical
spectroscopy, indicating that such a method is sensitive enough to detect tiny elongations of metallic
nano-particles. By experimentally simulating the electric device operation in a satellite orbit environment
exposed to radiation, the error frequency in on-orbit environment for Virtex-5 FPGA (Field Programmable
Gate Array), which is to be used for astrometric satellites, was evaluated as an acceptable level.

Tetsuro ISHII, Deputy Director, Department of Research Reactor and Tandem Accelerator

iv

JAEA-Review 2010-056

Contents
1.

ACCELERATOR OPERATION AND DEVELOPMENT ·································································· 1
1.1

Operation and usage of tandem accelerator and booster ································································ 3
T. Ishii, S. Abe,Y. S. Hanashima, N. Ishizaki, A. Osa, H. Tayama, M. Matsuda,
T. Nakanoya, H. Kabumoto, M. Nakamura, K. Kutsukake, Y. Otokawa,
T. Asozu and Y. Tsukihashi

1.2

KEK-JAEA joint RNB project ······································································································ 5S.C. Jeong on behalf of TRIAC Collaboration

1.3 Release of radioactive ion beams from a new ion source system in the JAEA-ISOL ····················· 7
Y. Otokawa , A. Osa, T. K. Sato and M. Matsuda
1.4 Recovery of acceleration field gradients of the superconducting booster
using high pressure water jet rinsing ···················································································· 9
H. Kabumoto, N. Ishizaki, S. Takeuchi, T. Yoshida, T. Ishiguro and K. Yamaguchi
1.5 Cluster beam acceleration project ································································································ 11
M. Matsuda, T. Asozu and K. Kutsukake
1.6High energy heavy ion Rutherford backscattering spectrometryat the JAEA-Tokai tandem accelerator ··················· 13
M. Nakamura, M. Matsuda, T. Asozu, M. Sataka, K. Takahiro and N. Matsunami

2.

NUCLEAR STRUCTURE ··············································································································· 15
2.1

Lifetime measurement for the first 2+ state in 162Gd ···································································· 17
D. Nagae, T. Ishii, R. Takahashi , M. Asai, H. Makii, A. Osa, T.K. Sato and S. Ichikawa

2.2

Decay study on fission products with on-line isotope separator ·················································· 19
M. Shibata, H. Hayashi, M. Asai, A. Osa, M. Oshima,
A. Kimura, M. Koizumi and T.K. Sato

2.3

Alpha-decay properties of 240,241Cf and the new isotope 236Cm ··················································· 21
M. Asai, K. Tsukada, N. Sato, T.K. Sato, A. Toyoshima, T. Ishii and Y. Nagame

2.4

Signature splitting property in the one-quasiparticle bands of 173W ············································· 23
Y.H. Zhang , X.H. Zhou, M. Oshima , M. Koizumi, Y. Toh, A. Kimura,
H. Harada, K. Furutaka, F. Kitatani, S. Nakamura, Y. Hatsukawa, M. Ohta,
K. Hara, T. Kin and J. Meng

2.5

Structure evolution of the yrast band in 101Pd ·············································································· 25
X.H. Zhou, H.B. Zhou,Y H. Zhang, Y. Zheng, M.L. Liu, N.T. Zhang,
Y.D. Fang, M. Oshima, Y. Toh, M. Koizumi, Y. Hatsukawa and M. Sugawara

2.6

Proton resonance elastic scattering of 68Zn

with thick target inverse kinematics method ·········· 27

N. Imai, Y. Hirayama, H. Ishiyama, S.C. Jeong, H. Miyatake, Y.X. Watanabe,
H. Makii, S. Mitsuoka, D. Nagae, I. Nishinaka, K. Nishio and K. Yamaguchi
2.7

Development of laser spectroscopy for radioactive isotopes in the rhenium region ····················· 29
H. Iimura, M. Koizumi, M. Miyabe, M. Oba and I. Wakaidav

JAEA-Review 2010-056

2.8Development of Si Δ E-E telescope using an annular-type E detector
for in-beam γ-ray spectroscopy ······················ 31
R. Takahashi, T. Ishii, H. Makii, M. Asai, Y. Wakabayashi, D. Nagae, K. Tsukada,
A. Toyoshima, M. Matsuda, A. Makishima, T. Shizuma, T. Kohno and M. Ogawa

2.9 Coulomb excitation of 130Ba at 1.1 MeV/nucleon ········································································ 33
N. Imai, Y. Hirayama, H. Ishiyama, S.C. Jeong, H. Miyatake, Y.X. Watanabe,
H. Makii, S. Mitsuoka, I. Nishinaka, K. Nishio and Y. Wakabayashi
2.10

Search for highly excited 11Be states in 9Li + d reactions ·························································· 35
T. Teranishi, H. Ishiyama, H. Miyatake, S.C. Jeong, Y.X. Watanabe, N. Imai,
Y. Hirayama, A. Osa, T. K. Sato, S. Mitsuoka, K. Nishio, M. Matsuda,
H. Makii, Y. Wakabayashi, T. Hashimoto, Y. Ito, Y. Kenmoku and K. Yamaguchi

3.

NUCLEAR REACTION················································································································· 37

3.1 Measurement of fission cross-sections in the reactions of 34,36S + 204,206,208Pb ····························· 39
J. Khuyagbaatar, D. Ackerman, M. Block, S. Heinz, F.P. Heβberger, S. Hofmann,
H. Ikezoe, B. Kindler, B. Lommel, H. Makii, S. Mitsuoka, I. Nishinaka, K. Nishio,
Y. Wakabayashi and S. Yan
3.2 Coulomb barrier distribution of quasi-elastic backscattering in 64Ni + 238U ································· 41
S. Mitsuoka, H. Ikezoe, K. Nishio, Y.X. Watanabe, S.C. Jeong,
Y. Hirayama, N. Imai, H. Ishiyama and H. Miyatake
3.3 Measurement of fission fragment mass distribution in the reaction of 40Ar + 238U ······················· 42
K. Nishio, I. Nishinaka, S. Mitsuoka, H. Makii, Y. Wakabayashi,
H. Ikezoe, K. Hirose and T. Ohtsuki
3.4

Fission properties of the neutron-deficient nucleus 180Hg
produced in heavy ion fusion reactions ···················· 44
A.N. Andreyev, R. Chapman, S. Pain, I. Tsekhanovich, M. Venhart, K. Nishio,
S. Mitsuoka, I. Nishinaka, H. Makii, Y. Wakabayashi, H. Ikezoe, J. Khuyagbaatar,
S. Yan, K. Hirose and T. Ohtsuki

3.5

Fission fragment anisotropy in heavy-ion-induced fission of actinides ········································ 46
I. Nishinaka, K. Nishio, M. Tanikawa, H. Makii,
S. Mitsuoka, Y. Wakabayashi and A. Yokoyama

3.6

Search for the new isotope 220Pu produced in the fusion reaction 82Kr + 140Ce ···························· 48
K. Nishio, Y. Wakabayashi, S. Mitsuoka, I. Nishinaka, H. Makii, H. Ikezoe,
M. Matsuda, K. Hirose, T. Ohtsuki, S. Yan, J. Khuyagbaatar and H. Miyatake

3.7

Study of 218U region near N=126 closed shell ············································································· 50
Y. Wakabayashi, K. Nishio, S. Mitsuoka, I. Nishinaka, H. Makii,
R. Takahashi, S. Yan, H. Miyatake and S. Ota

3.8

Production of 256Lr with the 249,250,251Cf(11B, xn) and 243Am(18O, 5n) reactions ··························· 52
N. Sato, M. Asai, K. Tsukada, T.K. Sato, A. Toyoshima, Z.J. Li,
T. Kikuchi, S. Ichikawa and Y. Nagamevi

JAEA-Review 2010-056

3.9 Measurement of fission probability of 240Pu
produced by nucleon transfer reaction 238U(18O, 16O)240U ···················································· 54
K. Nishio, I. Nishinaka, S. Mitsuoka, H. Makii, R. Takahashi, Y. Wakabayashi,
K. Furutaka, K. Hirose, T. Ohtsuki, S. Yan and S. Chiba
3.10

Development of a measurement system for (n, γ) cross sections
using the surrogate reaction methods ··················· 56
H. Makii, T. Ishii, D. Nagae, R. Takahashi, S. Mitsuoka, S. Chiba,
H. Miyatake, S.C. Jeong, N. Imai and Y. Hirayama

3.11

High energy alpha particles emitted from nuclear reaction ························································ 58
N. Imai, H. Ishiyama, Y. Hirayama, S.C. Jeong, H. Miyatake,
Y.X. Watanabe, H. Makii, S. Mitsuoka and K. Nishio

3.12

Development of GEM-MSTPC for measurement of the 8Li(α, n)11B reaction ··························· 60
H. Ishiyama, K.Yamaguchi , Y. Mizoi, Y.X. Watanabe, S.K. Das, M-H. Tanaka,
T. Hashimoto, Y. Hirayama, N. Imai, H. Miyatake, T. Nomura, T. Fukuda,
S. Mitsuoka, H. Makii, K. Nishio, T.K. Sato, M. Matsuda, Y. Wakabayashi,
H. Yamaguchi, S. Kubono and S. Hayakawa

4.

NUCLEAR CHEMISTRY ················································································································ 63
4.1 Cation-exchange behavior of rutherfordium, 104Rf
in H2SO4/HNO3 mixed solution ([H+] = 1.0 M) ······································ 65
Z.J. Li, A. Toyoshima, M. Asai, K. Tsukada ,T.K. Sato, N. Sato, T. Kikuchi,
X.H. Liang, Y. Kasamatsu, Y. Nagame, S. Goto, H. Haba, Y. Takeda, S. Ikarashi,
M. Murakami, M. Nishikawa, Y. Komori, K. Ooe, K. Akiyama and K. Sueki
4.2 Reduction of mendelevium using an electrochemistry apparatus ················································· 67
A. Toyoshima, K. Tsukada, M. Asai, T.K. Sato, Z.J. Li, N. Sato, T. Kikuchi,
Y. Kitatsuji. Y. Nagame, K. Ooe, Y. Kasamatsu, A. Shinohara, H. Haba and J. Even
4.3

On-line isothermal gas chromatographic behavior of group-5 elements as homologues of Db······ 69
T.K. Sato, K. Tsukada, M. Asai, A. Toyoshima, N. Sato,
Z.J.Li, T. Kikuchi, S. Liang and Y. Nagame

4.4

Gas-phase chemistry of Zr and Hf using carbon cluster transport system ···································· 71
S. Goto, H. Murayama, M. Murakami, T. Kojima, H. Kudo,
K. Tsukada, M. Asai, T.K. Sato, N. Sato and Y. Nagame

5.

NUCLEAR THEORY ······················································································································· 73
5.1 Analysis of surrogate reaction with unified model ······································································ 75
Y. Aritomo, S. Chiba and K. Nishio
5.2

Shell-model description of multi-particle multi-hole states around 16O andthe role of correlation energy ···································································· 77
Y. Utsuno and S. Chiba

5.3

Verification of the surrogate ratio method ··················································································· 79
S. Chiba and O. Iwamotovii

JAEA-Review 2010-056

5.4

New formulation with CDCC for evaluating incomplete and complete fusion cross sections········ 81
S. Hashimoto, K. Ogata, S. Chiba and M. Yahiro

5.5

Competition between allowed and first-forbidden transitions of beta decay
in the neutron-rich mass region relevant to the r-process nucleosynthesis ··········· 83
H. Koura

6.

ATOMIC PHYSICS AND SOLID STATE PHYSICS ······································································· 85
6.1 Coster-Kronig electron spectra of C- and N-like Oq+ (q = 1,2) ···················································· 87
K. Kawatsura, K. Takahiro, M. Sataka, M. Imai, H. Sugai,
K. Kawaguchi, T. Yoshimori, H. Shibata and K. Komaki
6.2 Charge state distribution of sulfur ions after penetration of C-foil targets ·································· 89
M. Imai, M. Sataka, H. Sugai, K. Kawatsura,
K. Takahiro, K. Komaki, K. Nishio and H. Shibata
6.3

Li diffusion in Li ionic conductors of NaTl-type intermetallic compounds ································· 91
H. Sugai, M. Sataka, S. Okayasu, S. Ichikawa, K. Nishio, S. Mitsuoka,
S.C. Jeong, I. Katayama, H. Kawakami, Y.X. Watanabe, H. Ishiyama,
N. Imai, Y. Hirayama, H. Miyatake, T. Hashimoto and M. Yahagi

6.4

Diffusion coefficient measurements on perovskite-type lithium ion conductor ··························· 93
S. Takai, S.C. Jeong, I. Katayama, H. Kawakami, H. Ishiyama, N. Imai, Y. Hirayama,
Y. Watanabe, H. Miyatake, M. Sataka, H. Sugai, S. Okayasu and T. Nakanoya

6.5

High-energy ion impact effects on atomic structure and optical propertyof In-doped ZnO films ···················································································· 95
N. Matsunami, M. Sataka, S. Okayasu and H. Kakiuchida

6.6Electrical property modifications of In-doped ZnO films by high-energy ion impact ············ 97
N. Matsunami, M. Sataka, S. Okayasu and H. Sugai

7.

RADIATION EFFECTS IN MATERIALS ······················································································· 99
7.1

Ion charge dependence on diameter of ion tracks in UO2 ··························································· 101
T. Sonoda, T. Sawabe, N. Ishikawa and M. Sataka

7.2 Microstructure observations and distribution of chemical compositions ofmetal precipitates in Zircaloy-2 irradiated with 210 MeV Xe ions ···················· 103
T. Sonoda, T. Sawabe, N. Ishikawa and M. Sataka
7.3

Electrical conductivity change in CeO2 irradiated with high-energy heavy ions ························ 105
N. Ishikawa and K. Takegahara

7.4

Effects of energetic heavy ion irradiation on the crystal structure in Gd2O3-doped CeO2 ··········· 107
Y. Tahara, B. Zhu, S. Kosugi, N. Ishikawa, Y. Okamoto,Y. Baba, N. Hirao, F. Hori, T. Matsui and A. Iwase

7.5

Effect of high temperature annealing on ferromagnetism
induced by swift heavy ion irradiation in FeRh alloy ············································ 109
S. Kosugi, N. Fujita, N. Ishikawa, F. Hori, T. Matsui and A. Iwase
viii

JAEA-Review 2010-056

7.6

Shape and property control of Zn and ZnO nanoparticles by swift heavy ions ·························· 111
H. Amekura, N. Ishikawa, K. Mitsuishi, Y. Nakayama and N. Kishimoto

7.7

Elongation of Au nanoparticle in SiO2 matrix irradiated with swift heavy ions ························· 113
M. Shirai, K. Yasuda, S. Matsumura and N. Ishikawa

7.8 Radiation damage test for Virtex-5 FPGA ················································································· 115
Y. Yamada, T. Tanaka, T. Inamori, H. Idobata, Y. Nagame,
K. Tsukada, T.K. Sato, S. Mitsuoka and K. Nishio
7.9 Transport properties of (-FeSi2) thin films ··············································································· 117
S. Okayasu and M. Sasase
7.10

Formation of metal microstructure induced by ion irradiation in Ag-zeolite ···························· 118
S. Okayasu and Y. Sasaki

7.11

Angular dependences of flux pinning properties
in YBCO thin films with crossed columnar defects ··················· 119
T. Sueyoshi, T. Sogo, K. Yonekura, T. Fujiyoshi, F. Mitsugi, T. Ikegami and N. Ishikawa

7.12

Swift ion implantation for fabrication of optical waveguides ·················································· 121
F. Qiu, T. Narusawa, A. Osa and M. Sataka

7.13

Dynamic nuclear polarization study of meso-scale spatial distribution offree radicals generated by carbon and electron beams ············· 123
T. Kumada , Y. Noda and N. Ishikawa

7.14

Track characterization of oxygen ions in solid state track detector ·········································· 125
M. Tampo, K. Nishio, Y. Fukuda, H. Sakaki, S. Mtsuoka and K. Kondo

8.

PUBLICATION IN JOURNAL AND PROCEEDINGS AND
CONTRIBUTION TO SCIENTIFIC MEETINGS ················ 127

8.1

Accelerator Operation and Development ············································································· 129

8.2

Nuclear Structure ·················································································································· 133

8.3

Nuclear Reaction ·················································································································· 135

8.4

Nuclear Chemistry ················································································································ 139

8.5

Nuclear Theory ····················································································································· 142

8.6

Atomic Physics and Solid-state Physics ··············································································· 148

8.7

Radiation Effects in Materials ······························································································ 149

9. PERSONNEL AND COMMITTEE ································································································ 151

9.1

Personnel ······························································································································ 153

9.2

Research Planning and Assessment Committee ··································································· 157

10. COOPERATIVE RESEARCHES AND COMMON USE IN JAEA ············································· 159

10.1

Cooperative Research Programs ························································································· 161

10.2

Common Use Programs in JAEA ······················································································· 163

ix

JAEA-Review 2010-056

目
1. 加速器の運転状況及び開発

次··········································································································· 1

1.1 タンデム加速器とブースターの運転及び利用状況
石井

哲朗、阿部

仲野谷

1.2

信市、花島

孝充、株本

進、石崎

裕史、中村

KEK-JAEA 共同 RNB 計画
TRIAC 共同研究代表

暢洋、長

暢彦、沓掛

······························································ 3
明彦、田山

健一、乙川

豪一、松田

義憲、遊津

誠、

拓洋、月橋

芳廣

········································································································· 5

鄭 淳讃

1.3 高温型 FEBIAD イオン源の放出時間測定 ····················································································· 7
乙川

義憲、長

明彦、佐藤

哲也、松田

誠

1.4 高圧純水洗浄による超伝導ブースターの加速電界の回復
株本

裕史、石崎

暢洋、竹内

1.5 クラスタービーム加速計画
松田

誠、遊津

末広、吉田

崇宏、石黒

·················································· 9
貴之、山口································································································· 11

拓洋、沓掛

健一

1.6 高エネルギー重イオンによるラザフォード後方散乱分光
中村

暢彦、松田

2. 原子核構造
2.1

162

和司

誠、遊津

拓洋、左高

正雄、高廣

················································ 13

克己、松波

紀明

···································································································································· 15

Gd の第一励起準位の寿命測定
長江

大輔、石井

牧井

宏之、長

哲朗、高橋
明彦、佐藤

························································································· 17
竜太、浅井

哲也、市川

雅人、
進一

2.2 オンライン同位体分離装置を用いた核分裂生成物の壊変特性の研究

2.3

2.4

240,241

173

柴田

理尋、林

木村

敦、小泉

Cf 及び新核種

2.5

雅人、長 明彦、大島

光生、佐藤

哲也

Cm のα崩壊 ························································································ 21

雅人、塚田

和明、佐藤

望、佐藤

豊嶋

厚史、石井

哲朗、永目

諭一郎

哲也、

W の 1 擬粒子バンドにおける指標分岐性
玉虎、周

真澄、

236

浅井

張

101

裕晃、浅井

····························· 19

小紅、大島

原田

秀郎、古高

太田

雅之、原

真澄、小泉

和禎、北谷

······································································· 23

光生、藤

かおる、金

文人、中村

暢輔、木村 敦、

詔司、初川

雄一、

政浩、孟 杰

Pd のイラストバンドにおける構造変化 ············································································ 25
周
大島

小紅、周

厚兵、張

真澄、藤

玉虎、郑 勇、柳 敏良、张 宁涛、方 勇得、

暢輔、小泉

光生、初川

雄一、菅原

昌彦

68

2.6 逆運動学厚い標的法を用いた Zn の陽子共鳴弾性散乱 ····················································· 27

2.7

今井

伸明、平山

賀一、石山

博恒、鄭 淳讃、宮武 宇也、渡辺 裕、牧井

光岡

真一、長江

大輔、西中

一朗、西尾

勝久、山口

宏之、

香奈子

レニウム領域の放射性同位体に対するレーザー分光の開発 ··········································· 29
飯村

秀紀、小泉

光生、宮部

昌文、大場

x

正規、若井田育夫

JAEA-Review 2010-056

2.8 インビームγ線分光のための円環型 Si 検出器を用いた SiΔE-E 検出器開発
高橋

竜太、石井

豊嶋

厚史、松田

哲朗、牧井
誠、牧嶋

2.9 1.1 MeV/nucleon での

2.10

章泰、静間

Ba のクーロン励起
博恒、鄭

牧井

宏之、光岡

淳讃、宮武

真一、西中

一朗、西尾

11

Li+d 反応による Be 高励起状態の探索
博恒、宮武

宇也、鄭

明彦、佐藤

哲也、光岡

真一、西尾

泰生、橋本

3. 原子核反応
S+

尚志、伊藤

和明、

雅生

宇也、渡辺

勝久、若林

裕、

泰生

··········································································· 35

高、石山

若林

俊之、小川

大輔、塚田

······································································· 33

賀一、石山

長

泰生、長江

俊行、河野

130

伸明、平山

9

34,36

雅人、若林

今井

寺西

3.1

宏之、浅井

················· 31

淳讃、渡辺

裕、今井

勝久、松田

洋介、見目

伸明、平山

誠、牧井

庸、山口

賀一、

宏之、

香奈子

···································································································································· 37

204,206,208

Pb 反応の核分裂断面積の測定····································································· 39

J. Khuyagbaatar、D. Ackerman、M. Block、S. Heinz、F.P. Heβberger、S. Hofmann、

3.2

3.3

64

40

池添

博、B. Kindler、B. Lommel、牧井

西尾

勝久、若林

Ni +

238

真一、西中

U 反応における後方準弾性散乱の障壁分布
真一、池添

博、西尾

今井

伸明、石山

博恒、宮武

238

一朗、

泰生、S. Yan

光岡

Ar +

宏之、光岡

勝久、渡辺 裕、鄭························································· 41

淳讃、平山

賀一、

宇也

U 反における核分裂片質量数分布の測定

西尾

勝久、西中

一朗、光岡

若林

泰生、池添

博、廣瀬

真一、牧井

························································· 42

宏之、

健太郎、大槻

勤

3.4 重イオン融合反応によって生成される中性子欠損核 180Hg の核分裂特性の測定··········· 44

A.N. Andreyev、R. Chapmann、S. Pain、I. Tsekhanovich、M. Venhart、西尾 勝久、
光岡

真一、西中

一朗、牧井

宏之、若林
健太郎、大槻

泰生、池添

J. Khuyagbaatar、S. Yan、廣瀬博、

勤

3.5 アクチノイド重イオン誘起核分裂における核分裂片角度異方性
西中

一朗、西尾

3.6 融合反応

82

Kr +

勝久、谷川

Ce による新同位体

西尾

勝久、若林

松田

誠、廣瀬

泰生、光岡

高橋

泰生、西尾

3.8

249,250,251

李

宇也、大田
18

3.9 核子移行反応

238

貴宏、市川

進一、永目

諭一郎

240

U( O, O)博、····················································· 50
宏之、

Am( O, 5n)反応による 256Lr の合成
哲也、豊嶋

16

明彦

晋輔

和明、佐藤

18

宏之、池添

一朗、牧井

雅人、塚田

子杰、菊池

泰生、横山

··························································· 48

一郎、牧井

真一、西中

竜太、S. Yan、宮武望、浅井Pu の探索真一、若林U 領域の原子核の研究

11

243

宏之、光岡

勤、S. Yan、J. Khuyagbaatar、宮武 宇也

勝久、光岡

Cf( B, xn) 及び

佐藤

218

220

真一、西中

健太郎、大槻

3.7 中性子魔法数 126 近傍である
若林

勝至、牧井

140

····································· 46········································ 52

厚史、U で生成される 240U の核分裂確率の測定

西尾

勝久、西中

一郎、光岡

真一、牧井

若林

泰生、古高

和禎、廣瀬

健太郎、大槻

xi

宏之、高橋
勤、千葉

竜太、
敏

·························· 54

JAEA-Review 2010-056

3.10 代理反応を用いた中性子捕獲断面積導出法の開発
牧井

宏之、石井

千葉

敏、宮武

哲朗、長江
宇也、鄭

大輔、高橋

淳讃、今井

3.11 核反応で生じる高エネルギーα粒子·························································· 56

竜太、光岡

伸明、平山

真一、

賀一

··················································································· 58

今井

伸明、石山

博恒、平山

賀一、鄭 淳讃、宮武 宇也、渡辺 裕、

牧井

宏之、光岡

真一、西尾

勝久

3.12 天体核反応率測定用ガス検出器 GEM-MSTPC の開発
石山

博恒、山口

加菜子、溝井

橋本

尚志、平山

賀一、今井

伸明、宮武

宇也、野村

亨、福田

共和、

光岡

真一、牧井

宏之、西尾

勝久、佐藤

哲也、松田

誠、若林

泰生、

山口

英斉、久保野4. 原子核化学
4.1

茂、早川

浩、渡辺

····················································· 60

裕、S.K. Das、田中

雅彦、

勢也

···································································································································· 63

H2SO4/HNO3 混合溶液（[H+] = 1.0 M）におけるラザホージウム(104Rf)の陽イオン交換挙動 ··········· 65
李

子杰、豊嶋

厚史、浅井

雅人、塚田

梁

小虎、笠松

良崇、永目

諭一郎、後藤

真一、羽場

宏光、武田

勇樹、五十嵐由希子、大江

一弘、秋山

和彦、末木

啓介

村上

昌史、西川

恵、小森

和明、佐藤

4.2 電気化学分析装置を用いたメンデレビウムの還元

4.3

豊嶋

厚史、塚田

和明、浅井

雅人、佐藤

北辻

章浩、永目

諭一郎、大江

哲也、佐藤

貴宏、

子杰、佐藤

良崇、篠原

厚、羽場

望、菊池

貴宏、

宏光、J. Even

Db を模擬した 5 族元素 Nb, Ta のオンライン等温ガスクロマトグラフ挙動
佐藤
李

哲也、塚田
子杰、菊池

和明、浅井

雅人、豊嶋

厚史、佐藤

貴宏、S. Liang、永目 諭一郎

後藤

真一、村山

裕史、村上

昌史、小嶋

貴幸、工藤

塚田

和明、浅井

雅人、佐藤

哲也、佐藤

望、永目

········································· 71

久昭、
諭一郎

···································································································································· 73

5.1 統一模型を用いた代理反応の記述
有友

嘉浩、千葉

敏、西尾

······················································································· 75

勝久

5.2 酸素 16 近傍の多粒子多空孔状態の殻模型的記述と相関エネルギーの役割
宇都野

穣、千葉

敏、岩本

··················· 77

敏

5.3 代理比反応法の成立条件
千葉················ 69

望、

4.4 カーボンクラスタ搬送を用いた Zr および Hf の気相化学研究

5. 原子核理論

訓、···························································· 67

哲也、李

一弘、笠松

望、菊池

······································································································· 79

修

5.4 不完全融合および完全融合反応断面積の離散化チャネル結合法を用いた新しい計算方法橋本

5.5

慎太郎、緒方

一介、千葉

敏、八尋

············· 81

正信

r 過程元素合成に関連した中性子過剰核におけるβ崩壊の許容遷移と第一禁止遷移の競合
小浦

寛之

xii

····················································· 83

JAEA-Review 2010-056

6. 原子物理及び固体物理················································································································· 85
q+6.1 炭素様及び窒素様 O (q=1,2)イオンのコスター・クロニッヒ電子スペクトル
川面

澄、高廣

克己、左高

川口

和弘、吉森

正雄、今井

貴史、柴田

誠、須貝

裕実、小牧

誠、左高

正雄、須貝

小牧

研一郎、西尾

宏行、川面

勝久、柴田

宏行、

研一郎

6.2 炭素薄膜標的通過後の S イオンの電荷分布今井········································································ 89

澄、高廣

克己、

裕実

6.3 NaTl 型金属間化合物 Li イオン伝導体中の Li 拡散
須貝
鄭

宏行、左高
淳讃、片山

正雄、岡安

今井

進一、西尾

宏金、渡辺

裕、石山

伸明、平山

··························································· 91

悟、市川

一郎、川上
賀一、宮武

宇也、橋本

勝久、光岡

真一、

博恒、

恭能、矢萩

正人

6.4 ペロブスカイト型リチウムイオン伝導性酸化物の拡散係数測定····································· 93

高井

茂臣、鄭

淳讃、片山

一郎、川上

宏金、石山

博恒、今井

伸明、平山

渡辺

裕、宮武

宇也、左高

正雄、須貝

宏行、岡安

悟、仲野谷

孝充

6.5 In ドープ ZnO の原子構造・光学特性への高エネルギーイオン照射効果
松波

紀明、左高

正雄、岡安

悟、垣内田

紀明、左高

7. 材料の照射効果
7.1

正雄、岡安

悟、須貝

························ 95······································· 97

宏行···························································································································· 99

UO2 に形成されるイオントラック径の照射イオン電荷依存性
園田

賀一、

洋

6.6 高エネルギーイオン照射による In ドープ ZnO の電気特性改質
松波·············· 87

健、澤部

孝史、石川

法人、左高

····································· 101

正雄、

7.2 210 MeV Xe イオンを照射したジルカロイ２の微細組織観察と金属析出物中の元素分布の解明
園田

健、澤部

孝史、石川

法人、左高

正雄

7.3 高エネルギーイオン照射した CeO2 の電気伝導度変化
石川7.4

法人、竹ヶ原······················ 103···················································· 105

圭介

ガドリニアを添加したセリアの結晶構造における高エネルギー重イオン照射効果······ 107
田原

佑規、朱

宝琳、小杉

晋也、石川

法人、岡本

平尾

法恵、堀

史説、松井

利之、岩瀬

彰宏

芳浩、馬場

7.5 鉄ロジウム合金の照射誘起強磁性における高温アニール効果
小杉

晋也、藤田

直樹、石川

法人、堀

史説、松井

雨倉

宏、石川

法人、三石

和貴、中山

佳子、岸本

学、安田

和弘、松村

晶、石川

彰宏

············································ 111

直樹

7.7 高速重イオン照射に伴う SiO2 中の金ナノ粒子の形状変化
白井······································· 109

利之、岩瀬

7.6 高速重イオン照射による Zn 系ナノ粒子の形状・物性制御

祐治、············································· 113

法人

7.8 民生用 FPGA Virtex 5 と外部メモリ用 SDRAM の放射線耐性評価
山田

良透、田中

利樹、稲守

孝哉、井戸端

塚田

和明、佐藤

哲也、光岡

真一、西尾

洋彰、永目

································ 115

諭一郎、

勝久

7.9 シリサイド半導体薄膜の輸送特性 ······················································································· 117
岡安

悟、笹瀬

雅人

xiii

JAEA-Review 2010-056

7.10

Ag-ゼオライトへのイオン照射による金属微小構造形成
岡安

悟、佐々木

············································ 118

優吉

7.11 交差した柱状欠陥を導入した YBCO 薄膜の磁束ピンニング特性の磁場角度依存性········ 119
末吉 哲郎、十河

雄大、米倉

健志、藤吉

孝則、光木

7.12 高エネルギー重イオン注入による光導波路の試作
F. Qiu、成沢

忠、長

明彦、左高

文秋、池上

知顕、石川

法人

························································ 121

正雄

7.13 動的核スピン偏極法を用いた、粒子線、電子線照射により固体中に生じたフリーラジカルの空間分布の研究
熊田

7.14

高之、能田

洋平、石川

法人

固体飛跡検出器における酸素イオン飛跡の感度特性に関する研究
反保

元伸、西尾

勝久、福田

祐仁、榊 泰直、光岡

8. 雑誌及び国際会議等の刊行物、学会発表
8.1 加速器の運転状況及び開発········· 123

真一、近藤··························· 125

公伯················································································ 127································································································· 129

8.2 原子核構造···························································································································· 133

8.3 原子核反応···························································································································· 135

8.4 核化学···································································································································· 139

8.5 原子核理論···························································································································· 142

8.6 原子物理及び固体物理
8.7 材料の照射効果········································································································· 148···················································································································· 149

9. 関連課室職員及び委員会··········································································································· 151

9.1 課室職員································································································································ 153

9.2 委員会···································································································································· 157

10. 共同研究及び施設供用············································································································· 159

10.1 共同研究課題······················································································································ 161

10.2 施設供用課題······················································································································ 163xiv

JAEA-Review 2010-056

CHAPTER 1
Accelerator Operation and Development

1.1

Operation and usage of tandem accelerator and booster

1.2

KEK-JAEA joint RNB project

1.3

Release of radioactive ion beams from a new ion source systemin the JAEA-ISOL

1.4

Recovery of acceleration field gradients of the superconducting booster
using high pressure water jet rinsing

1.5

Cluster beam acceleration project

1.6

High energy heavy ion Rutherford backscattering spectrometryat the JAEA Tokai tandem accelerator-1-

This is a blank page.

JAEA-Review 2010-056

1.1

Operation and usage of tandem accelerator and booster

T. Ishii 1 , S. Abe1, S. Hanashima1, N. Ishizaki1, A. Osa1, H. Tayama1, M. Matsuda1, T. Nakanoya1,
H. Kabumoto1, M. Nakamura1, K. Kutsukake1, Y. Otokawa1, T. Asozu1 and Y. Tsukihashi1

The tandem accelerator and booster were operated for experiments from July 11, 2009 to October 20, 2009,
and from December 10, 2009 to May 10, 2010. The total operation time of the tandem accelerator for
FY2009 (from April 1, 2009 to March 31, 2010) was 172 days and 25 different beams were delivered forexperiments. The experimental proposals and the usage of the beam times for FY2009 are summarized inTable 1 and Table 2, respectively.
In FY2009, an intense boron beam of 1 particle µA was supplied to experiments. A molecular beam of
CO2+ was accelerated from the in-terminal 14.5-GHz ECR ion source.

Table 1. Experimental Proposals.

Table 2. Usage of beam-times
in different research fields.

Research proposals accepted

Research field

Beam timeby the program advisory committee:
In-house staff proposals

7

Collaboration proposals

14
92

Number of experiment proposed

Total number of scientists participating in researchfrom outside355

in-house

432

Number of institutions presented(days)(%)

Nuclear physics

86

48.3

Nuclear chemistry

23

12.9

Atomic and material sciences

50

28.1

Accelerator development

19

10.7

178

100

total

40

Distributions of the terminal voltage and ion species for experiments are shown in Fig. 1 and Fig. 2,
respectively. Most of the beams were extracted from three negative ion sources, SNICS-2. The hydrogen
beam and multiply charged ion beams of helium-3, nitrogen, oxygen and rare gases were accelerated fromthe in-terminal ECR ion source. The ECR ion source was used as much as 41 % of all the beam time.
The superconducting booster was operated for a total of 21 days to boost the energies of 5 different beams
from the tandem accelerator, as is summarized in Table 3. These beams were used mainly for experimentsof nuclear physics. Twelve resonators out of 40 resonators were treated by a high-pressure water jet sprayrinse (HPWR).
The 7Li and proton beams were supplied to the TRIAC (Tokai Radioactive Ion Accelerator Complex)
1

Japan Atomic Energy Agency (JAEA)-3-

JAEA-Review 2010-056

experiments for 17 days. The radioactivities of 8Li, 123In and 142Ba were ionized and separated by the ISOL
and injected into the TRIAC.

17～18

5.2%
14.5%

16～17

40.7%
17.4%

14～15

4.7%
12～13
5.2%
11～12
3.5%
10～11 0.6%
9～10
4.1%
8～9 0%
7～8 1.2%
6～7
2.9%
＜6 0%
13～14

Beam Species

Terminal Voltages (MV)

15～16

CO2
197Au
184W
136Xe
90Zr
82Kr
68Zn
64Ni
58Ni
56Fe
40Ar
36Ar
36S
34S
28Si
22Ne
19F
18O
16O
15N
14N
12C
11B
7Li
3He
1H

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80

Terminal ECRIS : 40.9%
Ngative IS S-5 : 21.0%〃
S-4 : 25.3%〃
S-3 : 12.9%

0

5

10

Operating Time (days)

Fig. 2

Fig. 1 Distribution of terminal voltages.

Boosted energies

Beam times (days)

(MeV)
16

O

183

1

58

Ni

589, 623, 653

1

64

Ni

317-362 (29 energy points)

3

310-385 (15 energy points)

3

374

4

377, 380, 393

5, 1, 3

68

Zn

82

Kr

20

25

Distribution of beam species accelerated
for experiments.

Table 3. Boosted ion beams for experiments.
Beam species

15

Operating Time (days)-4-

JAEA-Review 2010-056

1.2

KEK-JAEA joint RNB project

S.C. Jeong 1 on behalf of TRIAC Collaboration

The Tokai Radioactive Ion Accelerator Complex (TRIAC) has been operated for nuclear physics andmaterials science experiments at JAEA-Tokai tandem accelerator facility under collaboration between KEK
and JAEA (TRIAC collaboration). Produced by the proton-induced fission reactions of natUC, theradioactive ion beams (RIBs) are extracted and mass-separated as singly charged ions by the isotope
separator on-line (ISOL) of JAEA. They are charge-bred to higher charge states with a charge-to-mass
ratios of about 1/7 using charge breeding electron cyclotron resonance ion source (CB-ECRIS) called as
KEKCB. And then, the charge-bred RIBs are accelerated by using a series of heavy ion linacs, thesplit-coaxial radiofrequency quadrupole (SCRFQ) and the inter-digital H (IH) linacs. In FY 2009,
radioactive isotope beam of 142Ba at 1.1 MeV/A has been developed for a future experiment. The
background ion which had the same q/A ratio of 142Ba22+ and originated from KEKCB was identified as
71
11

Ga11+. The following experiments were carried out in FY 2009: (1) Search for highly excited states in

Be states in 9Li + d reactions (RNB08-K08), (2) Diffusion study of ionic conductors using the short-lived

isotopes (RNB09-K01/K07). Some details of the experiments can be found in this report.
In addition to the experiments with RIBs, we arealso going to directly measure the 12C(,)16O
reaction cross sections at stellar energies using astable  beam. To carry out the experiment, an
intense pulsed beam with the width less 10 ns andthe interval between 250 ns and 500 ns is needed.
We

have

developedabrand-newpseudosaw-tooth wave pre-buncher and a multi-layer
chopper. The pre-buncher is a two-gaps buncher
having a single drift tube. The RF voltage appliedon the tube is synthesized with two and threetimes

higherharmonics

waves

and

the

fundamental wave, giving a rise to a pseudo
saw-tooth wave form. Particles passing throughthe two gaps are bunched effectively by thepseudo saw-tooth wave voltage. The pre-buncher
was installed at the entrance of SCRFQ. In order
to efficiently deflect the beam particles ofFig. 1 Beam bunch structure with pre-buncher

out-of-bunch phase, which are generated by theoff (a) and pre-buncher on (b).

transient time portion of the saw-tooth wave-form,
1

High Energy Accelerator Research Organization(KEK), corresponding author: N. Imai,-5-

JAEA-Review 2010-056

Fig. 2 (Left) Distribution of residual activities of 111In in the plasma chamber as a function of azimuthal
angle () and longitudinal position (z). Residual activities of 140Xe (Right). See the text for details.
the beam chopper was also placed upstream of the pre-buncher. The chopper has 19 electrodes of 40 mm
wide, 10 mm long, and 0.1 mm thick piled up with gaps of 1.9 mm vertically to the beam direction and asquare-shape electric potential (120 V in maximum, 2-4 MHz in repetition frequency) is applied to every
two electrode (One grounded electrode is interposed between two electrodes on the electric potential).
The beam test of the pre-buncher with 2 MHz frequency was performed using 16O4+ and 12C3+ beams
supplied by KEKCB. The clear bunch structure with an interval of 500 ns was observed as shown in Fig.1,
although there exists a small fraction of the beam failed to be bunched. A typical pulse width of the beam
after acceleration (1.1 MeV/nucleon) was achieved to have a 2 ns in standard deviation at the target
position about 10 m away from the exit of IH-linac. The incomplete beam-bunching could be removed by
the operation of the beam chopper to be installed upstream of the pre-bunchar.
The origin of smaller charge breeding efficiencies for the non-gaseous elements as compared to those of
gaseous elements was investigated. The charge breeding efficiencies can be regarded as the product of two
efficiencies; the capture efficiency for single charged ions by the ECR plasma and the ionization efficiency
for step-by-step charge breeding. In general, for the ECRIS the latter efficiency is supposed to be
independent of the element. And thus, the difference of charge breeding efficiencies may attribute to theinadequate capture by the ECR plasma in the charge breeding processes. In order to study the difference inthe capture process, we injected a metallic element 111In into the ECR plasma in FY2008. The ions werecharge-bred as usual, then the activities from the indium failed to be extracted as multi-charged ions were
measured. In the FY 2009, we injected a gaseous element 140Xe into the ECR plasma. The distribution ofresidual activities of 140Xe was compared with that of 111In as shown in Fig.2. We observed well-localized
in azimuthal distribution with 120-degrees periodicity for both elements, particularly prominent around theminimum (Bmin at Z~200 mm) of the axial field configuration for electron confinement. However, for the111

In, the asymmetric distribution with a strongly localized around ~300 deg. and Z~200 mm wasobserved around Bmin, while the 140Xe distribution had almost same peak heights (symmetric). Further
analysis is in progress.

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JAEA-Review 2010-056

1.3

Release of radioactive ion beams from a new ion source system in the JAEA-ISOL
Y. Otokawa 1 , A. Osa1, T. K. Sato1 and M. Matsuda1

We have improved an ion source system in the isotope separator on-line at Japan Atomic Energy Agency(JAEA-ISOL), in order to separate of short-lived isotopes produced by proton-induced fission of 238U. The
ion source system is a forced electron beam induced arc discharge (FEBIAD) type ion source with a target
container. The system attained operation temperature of nearly 2000 oC at the target container, as a result of
reduction in volume of the ion source and the target container, introduction of heating method by electron
bombardment, and improvement to the heat shield. A schematic view of the ion source is shown in Fig. 1.
We measured time intervals between production and separation (release time) of radioactive ion beams
from the ion source system, using 238U of 640 mg/cm2 with a proton primary beam of 30 MeV, 350 nA
from JAEA-Tokai tandem accelerator. Mass-separated isotopes, after turning off the proton primary beam,
were collected using Mylar tape from the tape transport system for the measurement of release time. The
collected isotopes were periodically transported to a measuring position. The -ray spectra of each interval
were stored in one of 16 blocks of 64 k channels memories. The storing block was switched on at the sametime as the collected radioactive source was transported to the measuring position. The whole measurement
cycle was repeated in order to increase the statistics. Release time distributions of 121gIn are shown in Fig. 2.
The release properties were evaluated based on a phenomenological analysis. Time dependences of the
decay corrected counts were fitted by the following equation:

N ' (t )   Ai exp(i t ) .
i 1, 2

The release time i = 1 / i and the fractional rate Ai / i for Kr, In, and Xe atoms deduced from the fit to thepresent date are summarized in Table 1 together with those of the previous FEBIAD, the surface ionization
ion source system at JAEA-ISOL [1,2], and reported values at different facilities [3-6]. We successfully
shortened the release times for indium, krypton and xenon. As a result, we obtained short-lived isotopes of93

Kr (T1/2 = 1.286 s), 129In (T1/2 =0.61 s) and 141Xe (T1/2 =1.73 s) with the intensity of 103 ions/s using the

JAEA-ISOL with the new ion source system.

1

Japan Atomic Energy Agency (JAEA)-7-

JAEA-Review 2010-056

Fig. 1 Schematic view of the new ion source

Fig. 2 Release time distributions of 121gIn at thesystem.

target temperature of 1950 oC

Table 1. Release times and fractional rates obtained from a one and/or two component fit to the Kr, In, and
Xe release data.
Isotope91
Kr

Half-life /s
8.57

Ion source
FEBIADa
Previous FEBIADb

121g

23.1

FEBIADa

123g

In

5.98

139

Xe

39.68

Previous FEBIADb
SISc
FEBIADa

In

Previous FEBIADb

Release time /sτ1:2.3
τ2:54.1
τ1:3.1
τ2:46.9
τ1:1.8
τ2:15.8
τ1:7
τ1:1.7 at 2250℃
τ1:4.6
τ2:91.9
τ1:12
τ2:>300

FEBIAD operated at 1950 oC.
Previous FEBIAD operated at 1550 oC.
c
SIS(Surface ionization type ion source) operated at 2250 oC.
dValue was converted to mean life.

Fraction rate
20%
80%
21%
79%
27%
73%
100%
100%
21%
79%

a

e

b

f

Reported value /sd
1.5e, 3.5f, 16g

OSIRIS at 2400 oC.
ISOLDE at 1900-2000 oC.
g
IRIS at 2050-2100 oC.
h
PARRNe at 2000 oC.

References[1] A. Osa et al., Nucl. Instrum. Methods Phys. Res., B266 (2008) 4394-4397.
[2] A. Osa et al., Nucl. Instrum. Methods Phys. Res., B266 (2008) 4373-4377.
[3] Fogelberg et al., Nucl. Instrum. Methods Phys. Res., B70 (1992) 137-141.
[4] H. M. Evensen et al., Nucl. Instrum. Methods Phys. Res., B126 (1997) 160-165.
[5] Andrighetto et al., Nucl. Instrum. Methods Phys. Res., B204 (2003) 267-271.
[6] Roussire et al., Nucl. Instrum. Methods Phys. Res., B246 (2006) 288-296.

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1.8e, 1.6f, 6h
22e, 11.7f, 30g

JAEA-Review 2010-056

1.4

Recovery of acceleration field gradients of the superconducting booster
using high pressure water jet rinsing

H. Kabumoto 1 , N. Ishizaki1, S. Takeuchi1, T. Yoshida 2 , T. Ishiguro2 and K. Yamaguchi2

We have carried out the high pressure water jet rinsing (HPWR) to re-condition the superconducting
booster since 2006. The HPWR is a technology of removing small contaminations on resonator surfaces,
and a very effective method to recover the acceleration field gradients of superconducting resonators. We
applied the HPWR to 12 resonators of 3 cryostats (No.6, 7, 8) in 2009.
Figure 1 shows how the average acceleration field gradient Eacc across the superconducting boosterchanged in the years between 2003 and 2010. The average Eacc was decreasing little by little each year, andit was about 3.9MV/m in 2005 and 2006. We started the HPWR to on-line resonators in 2006. It required
about 4 weeks to carry out the HPWR for every 4 resonators of 1 cryostat, in which period wedisassembled and re-assembled all parts in the cryostat, including the resonators, mechanical tuners, RF
couplers, thermometers, etc. Furthermore, the inside of cryostat needed to be cleaned up. There were manysmall contaminations on the inner and bottom walls of cryostat, mainly powders of molybdenum comingfrom the molybdenum coated gears of mechanical slow frequency tuners, with which low friction has beenrealized. It seemed that the field emission was caused by this molybdenum powder on the surface ofsuperconducting resonators. We have finished the 28 resonators of 7 cryostats (No.3, 5, 6, 7, 8, 9, 10) by
2009. The average acceleration field gradient Eacc all over the 40 resonators was recovered to 4.4MV/m.

Average of acceleration field gradient
Eacc [MV/m]

4.6

4.4

4.2

Start the HPWR
↓

4.0

3.8

3.6
2003
Jun-03 2004
Jun-04 2005
Jun-05 2006
Jun-06 2007
Jun-07Year

Fig. 1

1
2

2008
Jun-082009
Jun-092010
Jun-10

The average acceleration field gradient Eacc across the superconducting boosterchanged in the years between 2003 and 2010.

Japan Atomic Energy Agency(JAEA)ATOX Co., Ltd.
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JAEA-Review 2010-056

References[1] H. Kabumoto et al., JAEA-Tokai TANDEM Ann. Rep. 2008, JAEA-Review 2009-036 (2009) 13-14.
[2] H. Kabumoto et al., JAEA-Tokai TANDEM Ann. Rep. 2007, JAEA-Review 2008-054 (2008) 16.
[3] H. Kabumoto et al., JAEA-Tokai TANDEM Ann. Rep. 2006, JAEA-Review 2007-046 (2008) 15-16.

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JAEA-Review 2010-056

1.5

Cluster beam acceleration project
M. Matsuda 1 , T. Asozu1 and K. Kutsukake1

On

the

high

voltageterminalofthe

JAEA-tandem accelerator, an ECR ion source(ECRIS) has been installed to extract andaccelerate positive ions such as rare gas ones.
By taking advantage of the ECRIS, we haveattempted to accelerate cluster ions such as C60,
expecting high energy and intense cluster beams,
since the charge exchange is unnecessary.
The schematic diagram of the accelerator
system is shown in Fig. 1. The cluster beam
extracted from the ECRIS is bent upwards witha 90o injection magnet (BM EC-1) and ispre-accelerated by 80 kV acceleration tube. A
180o bending magnet (BM TL-1) is used to
select a cluster ion having specific mass andcharge state and to guide it to the 20 MV
acceleration tube. Here, since the magnetic fieldstrength of the BM EC-1 is ME/q2 ≦ 0.28,
extraction voltage is decreased to several kV.
On the other hands, since the strength of the
BM TL-1 is enough as ME/q2≦55, in manycases, it is not necessary to decrease thepre-acceleration voltage. Table 1 shows therelation

betweenextraction

voltageandaccelerable ion mass (carbon atoms). The
accelerated cluster beam was guided to the newtarget room in the second basement level. To
accelerate

cluster

ions

with

reasonabletransmission efficiency and to know the
maximum m/q value, the performance ofexisting beam handling system was checked. A
test was carried out to guide the beam throughthe 20 mm diameter duct of BM 04-1 and focus
Fig. 1 Schematic diagram of the accelerator
1

Japan Atomic Energy Agency (JAEA)- 11 -

JAEA-Review 2010-056

the beam at a target position using Xe beams with various charge states. A beam profile monitor (BPM) anda Faraday cup (FC) were newly installed directly under the BM 04-1 12 m downstream of the magnetic
quadrupole lens (MQ 03-1). At the terminal voltage of 15 MV, the beam transport through the BM 04-1
was succeeded without a significant loss of the beam current. From this test we obtained the data shown in
Fig.2, which represents the current to drive MQ 03-1 needed to guide and focus the beam. Considering the
maximum current of 25 A for MQ 03-1 and the drift length to a target position (focus point) located 16 m
downstream from MQ 03-1, it was found that cluster ions up to m/q = 200 can be available.
We are planning to install a beam chopper system at the high voltage terminal for beam current attenuationand time-of-flight (TOF) experiments. The repetition frequency will be 50 kHz and pulse width 0.1 to 10 s.
We expect single ion hit experiments such as coulomb explosion imaging using an attenuated beam about
10-1000 ions per second and a TOF experiment which measures the mass and energy of a secondary ion
using a pulsed cluster beam. The intense cluster beams will also enable more progressive researches into
solid-state physics and materials sciences as well as cluster physics.
Table. 1 Extraction voltage and accelerable ion mass number.
Extraction voltage [kV]

20

15

10

5

3

2

1

0.39

Mass [amu]

14

18

28

56

93

140

280

720

Carbon atoms

C1

C1

C2

C4

C7

C11

C23

C60

10

12.7

Magneteic Quadrupole setteing current [A]

25

20

15

Xe3+
Xe6+

10

Xe9+
Xe

5

0

14+

Xe22+

0

5

15

1/2

(mass/charge)

Fig. 2 The relation between a mass to charge ratio of Xe ions andmagnetizing current of MQ 03-1.

References[1] M. Matsuda et al., JAEA-Tokai Tandem Ann. Rep. 2008, JAEA-Review 2009-036 (2009)11-12.

- 12 -

JAEA-Review 2010-056

1.6High energy heavy ion Rutherford backscattering spectrometryat the JAEA-Tokai tandem accelerator

M. Nakamura 1 , M. Matsuda1, T. Asozu1, M. Sataka1, K. Takahiro2 and N. Matsunami3

The heavy ion Rutherford backscattering spectrometry (HIRBS) is an ion beam analysis method that has anadvantage for the analysis of heavy elements in materials. The dependence of mass resolution (δM) on
target mass (M) and projectile mass (m) can be estimated as follows [1]:
2

1

 2
2
2
2  m  cos  
sin

M
m



M 

, K 
 ,E i  dK 
mM





E  dM where K is the kinematic factor, δE/Ei is the energy resolution of the detection system, Ei is incident energyof the projectile and θ is the scattering angle of projectile with respect to the beam axis. Figure 1 shows thedependences of δM on M for projectiles of m = 1, 2, 4, 12, 22 and 40. Here δE/Ei = 0.01 and θ = 165° are
assumed. Projectiles of m = 12 and 22 are expected to offer better mass resolution than H and 4He ion fortargets of M > 40.
We started the experiment to measure the HIRBS at JAEA-Tokai tandem accelerator facility. The mass
resolution of the HIRBS depends on the mass of projectile and target, the energy resolution of scattering
ion, the optimization of kinematics geometry and so on. Since the resolution was expected to be high forthe target mass around 70, 22Ne ion was selected as a projectile. In kinematics, the higher the energy of ion
beams, the higher energy resolution is provided, but we need to stay in the region that nuclear reactions do
not occur. 22Ne ions were accelerated by the tandem accelerator up to 1.25 MeV/u. The targets were a thinAu foil (1 nm) and Cu foil (10 nm) deposited on Si substrate, GaAs single crystal and Ge single crystal.
The ion detector was a Si detector (ORTEC: BU-012-050-100) with a 3.2 mmφ aperture. A schematic viewof the experimental set-up is shown in Fig. 2.
Figure 3 shows HIRBS spectra from Au foil (A), Cu foil (B), GaAs crystal (C) and Ge crystal (D). The
measurement time was several hours per spectrum. The energy resolution of the detection system was about
1.2 % (FWHM@18MeV) from the analysis of a Au foil spectrum. Enough mass resolution was achieved,
although the energy resolution was less than that of a typical RBS using He beam and high resolution
detection system. Mass resolution higher than 2 amu was performed as shown in Fig. 3 (B) and (C).
We confirmed that the high energy HIRBS has enough mass resolution to analyze heavy elements inmaterials with a Si detector. Presently, we are also pursuing the RBS for depth profiling and another ion
beam analyses.
1Japan Atomic Energy Agency (JAEA)
Kyoto Institute of Technology
3
Nagoya University EcoTopia Science Institute2- 13 -

JAEA-Review 2010-056

Fig. 1 Mass resolution (δM) on target mass (M) for

Fig. 2 Schematic view of the detection

projectile mass (m).

set-up.

Fig. 3 HIRBS spectra from Au foil (A), Cu foil (B), GaAs crystal (C) and Ge crystal (D).
References[1] J.R. Tesmer and M. Nastasi, “Handbook of modern ion beam materials analysis” (1995).

- 14 -

JAEA-Review 2010-056

CHAPTER 2
Nuclear Structure

2.1

Lifetime measurement for the first 2+ state in 162Gd

2.2

Decay study on fission products with on-line isotope separator

2.3

Alpha-decay properties of 240,241Cf and the new isotope 236Cm

2.4

Signature splitting property in the one-quasiparticle bands of 173W

2.5

Structure evolution of the yrast band in 101Pd

2.6

Proton resonance elastic scattering of 68Zn
with thick target inverse kinematics method

2.7

Development of laser spectroscopy for radioactive isotopes in the rhenium region

2.8

Development of Si Δ E-E telescope using an annular-type E detector
for ion-beam -ray spectroscopy
130

Ba at 1.1 MeV/nucleon

2.9

Coulomb excitation of

2.10

Search for highly excited 11Be states in 9Li + d reactions- 15 -

This is a blank page.

JAEA-Review 2010-056

2.1

Lifetime measurement for the first 2+ state in 162Gd

D. Nagae1, T. Ishii1, R. Takahashi 2, M. Asai1, H. Makii1, A. Osa1, T.K. Sato1 and S. Ichikawa1

Gadolinium isotopes lie in a well deformed region between the proton closed shells of Z = 50 and 82. In
previous experiments, we identified new neutron-rich europium isotopes 163, 164, 165, 166Eu [1, 2], and foundthat the energies of the first 2+ states E(2+) in even-even 64Gd isotopes show the local minimum at N = 98,
which is similar to those in 66Dy isotopes [3]. On the other hand, the E(2+) values of 68Er, 70Yb, and 72Hfisotopes monotonously decrease with the neutron number approaching the N = 104 midshell. In order tostudy the mechanism of the local minimum at N = 98, we have measured the lifetime of the first 2+ state at
71.5 keV in 162Gd to deduce the B(E2) value by means of the – delayed coincidence technique formass-separated 162Eu isotope.
The experiment was performed using an isotope separator on-line (ISOL) [4]. The 162Eu isotope wasproduced in 32-MeV proton-induced fission with an UCx target (630 mg/cm2) set in the surface ionization
type ion source [1]. Reaction products were ionized in the ion source, extracted, and mass-separated by the
ISOL. The mass-separated 162Eu (T1/2 = 10.6(10) s) isotope was transported to a tape system. In the tapesystem, 162Eu isotope was collected on aluminized Mylar tape, and transported to the detection port atprescribed time intervals. The tape was moved every 20 s. The detection position was equipped with a
Pilot-U plastic scintillator (60 mm × 63 mm × 1-mm thickness) and a BaF2 scintillator (38-mm diameter ×
5-mm thickness) to detect  and  rays, respectively. A Ge detector was placed at the detection position tomonitor the implanted RI beam. Time signals of the plastic scintillator and the BaF2 scintillator weregeneratedby

ORTEC-583B

constant

fractiondifferential

discriminators.

An

ORTEC-567

time-to-amplitude converter (TAC) was used for measuring a time interval from the time signal of theplastic scintillator to that of the BaF2 scintillator. The lifetime was deduced from the slope of the timeinterval spectrum.
A-ray spectrum measured with the Ge detector is shown in Fig. 1. In this spectrum, KX rays of Gd andsome  rays associated with the  decay of 162Eu are observed.  rays associated with the  decay of 143Ba
are also observed, which were mass-separated as a fluoride form. In Fig. 1, a -ray spectrum measured with
the BaF2 detector in coincidence with TAC signals is also shown. In this spectrum, KX-ray and the 71.5
keV -ray peaks are observed. The energy gate was set at the high-energy portion of the 71.5 keV peak to
avoid the influence of the KX rays. A time interval spectrum for the first 2+ state was obtained as shown in
Fig. 2. This spectrum includes the prompt time components from Compton events caused byhigher-energy rays. The lifetime was deduced by fitting an exponential decay curve, aexp(-t/) + b, by aleast-2 method. Contributions of the lifetimes of higher-lying states were neglected because their lifetimes
are expected to be short. From the fitting analysis, we obtained the lifetime of the first 2+ state as

1
2

Japan Atomic Energy Agency (JAEA)
Tokyo University of Science (TUS)- 17 -

JAEA-Review 2010-056

Fig. 1 Energy spectra for 162Gd. -ray spectrum measured with the Ge detector (dashed line), and -ray
spectrum measured with the BaF2 detector (solid line) in coincidence with TAC signals.

 = 3.98(8) ns; the error was estimated from the spread of various fitted values obtained by changing thefitting range.
The B(E2;0+ → 2+) value was calculated from the measured lifetime, total internal conversion coefficientT, and the transition energy E by using the formula 401 .81 10.
E
13

B E 2;0   2  

5

T



The internal conversion coefficient was taken from the ICC code in the program ESCL8R [5] as T = 9.063.
The transition energy was measured in the previous experiment [1] as E= 71.52(5) keV. The B(E2;0+ →2+) value of 162Gd was deduced as B(E2;0+ → 2+) = 5.45(11) e2b2.

Fig. 2 Time spectrum of 162Gd. The result of the fitting analysis is shown by a solid curve.
References[1] A. Osa et al., Nucl. Instrum. Methods Phys. Res., B266 (2008) 4394-4397.
[2] T.K. Sato et al., JAEA Tandem Ann. Rep. 2006, JAEA-Review 2007-046 (2008) 32-33.
[3] M. Asai et al., Phys. Rev., C59 (1999) 3060-3065.
[4] S. Ichikawa et al., Nucl. Instrum. Methods Phys. Res., B70 (1992) 93-100.
[5] D. C. Radford, Nucl. Instrum. Methods Phys. Res., A361 (1995) 297-305.

- 18 -

JAEA-Review 2010-056

2.2 Decay study on fission products with on-line isotope separator
M. Shibata1, H. Hayashi1, M. Asai2, A. Osa2, M. Oshima2, A. Kimura2, M. Koizumi2 and T.K. Sato2

Beta-decay energies (Q) are important for evaluation of the decay heat of the nuclear power plants in nuclear
engineering. They are also important to determine atomic masses precisely which are fundamental physicalquantities and play an important role for study on structure of unstable nuclei or nucleosynthesis in astrophysics. We
had studied Qmeasurements of fission products with a total absorption detector, composed of a clover detector and
BGO Compton suppressors [1]. In this year, the Q of fission products Eu and Gd (A>160) were measured and theresults were compared to systematics or some theoretical predictions.
Uranium carbide (UC2) target containing 670 mg･cm-2 238U was bombarded with 32 MeV proton beams with theintensity of about 0.6-1 A generated by the TANDEM accelerator at JAEA. The 160,161,163,165,166Eu and daughter
nuclei 163,165Gd were separated from the fission products with an on-line mass separator(ISOL) and mass-separated
nuclides were implanted into a computer-controlled movable thin Mylar tape. The half-lives of the nuclei of interest
are between 1 s and 60 s. The Gd isotopes were measured after decaying out of their parent Eu isotopes. Singles
spectrum and coincidence spectrum with the BGO detectors were measured simultaneously for each nucleus. Eachnuclide was measured over 10 hours to accumulate adequate statistics. The detector was shielded with 10 cm thicklead blocks and 10cm thick 10% borated polyethylene ones. The counting rate was lower than 0.2 kcps for all
nuclides, then, pulse pile-up does not matter. The total absorption events were extracted according to the method in
the previous report.[1]Typical spectra and analysis with folding method including one component approximation for 165Eu are shown in Fig.
1. In this method, the spectra were analyzed by assuming an allowed -transition, which is mixed with an unique firstforbidden with ratio  depopulating to a pseudo level. The method was described in the previous reports[1,2]. The
Eu was analyzed properly with applying the level at 1500 keV and only allowed -transition. This method was165

applied to each nuclide and the folded spectrum reproduced the experimental one well in the region of ~1 MeV below
endpoint of each spectrum. The Qsof the 160,161,163,165,166Eu and daughter nuclei 163,165Gd were preliminarily
determined to be 4480(30), 3722(30), 4829(65), 5729(65), 7322(300), 3187(40) and 4113(65) keV, respectively. The
value for the new isotopes 166Eu[3] was proposed for the first time. The others are in agreement with the previous
values determined with the BGO total absorption detector[4] and each uncertainty is smaller. Figure 2 showsdifferences between AME2003[5] and the present result or some theoretical mass formulae in this mass region.
AME2003 and some theoretical model predict the experimental atomic mass well. On the other hand, some modelcannot predict them in the region which have no experimental data. It says the experimental values can be useful tocheck the reliability of theoretical mass formulae and it is also respectful to improve the model. In conclusion, the Q
of seven nuclides were determined with the total absorption detector. The experimental data are useful to check of thereliability of mass formulae and also useful to develop nuclear models.

1

Nagoya University

2

Japan Atomic Energy Agency (JAEA)- 19 -

JAEA-Review 2010-056

Present study is the result of "Study on nuclear data by using a high intensity pulsed neutron source for advanced
nuclear system" entrusted to Hokkaido University by the Ministry of Education, Culture, Sports, Science andTechnology of Japan (MEXT).
200

165

165

Eu

Eu

=0
SQRT(N)SQRT(N)

Singles
Coincidence
S-1.25C

100

1500 keV
40

0

0
0

S-1.25C(Exp)
Folded

80

2000
4000
Energy / keV

6000

3000

4000

5000
6000
Energy / keV

7000

Fig. 1 Typical spectra (Singles, Coincidence with BGO and total absorption (S-1.25C))(left) and theanalyzing results by folding methods (right) for 165Eu.
3

Present

6

2

Myers
6

Satpathy

6

Comay

Spanier
66

JaneckeDifference / MeV

7

Masson6

DusselMoller

6

Eu

8

Koura

6

Goriely
Duflo

9

1

0

-1

Exp.
-2
150

155

160
Mass Number (A)

165

170

Fig. 2 The differences between AME2003[5] and the present results, some theoretical predictions[6-9]. AME2003
is agreement with the present results. On the other hand, some predictions show no predictability far off thestability.

References[1] M. Shibata, et al., JAEA-Tokai Tandem Annual Report 2008, JAEA-Review 2009-036(2009) 33-34.
[2] H. Hayashi et al., Nucl. Instrum. Methods Phys. Res., A613 (2010) 79-89.
[3] H. Hayashi et al., Eur. Phys. J., A34 (2007) 363-370.
[4] T. K. Sato et al., JAEA-Tandem Annual Report 2006, JAEA-Review 2007-046 (2007) 32-33.
[5] G. Audi, A. H. Wapstra and C. Thibault, Nucl. Phys., A729 (2003) 337-676.
[6] These values are summarized in At. Data Nucl. Data Tables, 39 (1998).
[7] W. D. Myers et al., Ann. Phys. (N.Y.), 204 (1990) 401-431.
[8] H. Koura et al., Prog. Theor. Phys., 113 (2005) 305-325.
[9] J. Duflo and A.P Zuker, Phys. Rev., C52 (1995) R23-R27.

- 20 -

JAEA-Review 2010-056

2.3

Alpha-decay properties of 240,241Cf and the new isotope 236Cm

M. Asai 1 , K. Tsukada1, N. Sato1, T.K. Sato1, A. Toyoshima1, T. Ishii1 and Y. Nagame1

Energy of the first 2+ state E(2+) in even-even nuclei is a good probe to explore nuclear shell structure anddeformation in frontier regions of nuclear chart. In general, E(2+) takes the maximum at the closed shell,
decreases with increasing number of valence nucleons, and takes the minimum around the midshell where
nuclei are well-deformed. Actinide nuclei are known to be well-deformed, indicating that they should belocated around the midshell. However, because of lack of experimental data, systematic trend of E(2+) in
actinide nuclei is still unclear. In this research program, we systematically measured E(2+) of even-even Pu,
Cm, Cf, and Fm isotopes through high-resolution -fine structure measurements. Although the data
analysis is still in progress, we report here some experimental results obtained in the -fine structure
measurement for 240Cf: -decay properties of 240,241Cf and the new isotope 236Cm.
An 233U target with a thickness of 480 g/cm2 was bombarded with a 12C beam to produce 240Cf. The beamenergy was 80 MeV on target. Reaction products recoiling out of the target were transported through a
25-m long capillary with a He/KCl aerosol jet into a rotating-wheel  detection system [1], and deposited
on a thin foil eighty of which were set on the wheel. The wheel periodically rotated at 60-s intervals tomove the deposited sources to six consecutive detector stations each of which was equipped with ahigh-resolution Si detector (PIPS). To measure  fine structure ( energies and intensities) very precisely,
the Si detectors were set at the distance with a solid angle of 12% of 4 from the source. This setup reduces
a low-energy tail of  peaks and also reduces energy sum between  particles and subsequently emitted
conversion electrons, Auger electrons, and low-energy X rays which considerably distorts the measured
-energy spectrum. The -energy resolution of 12 keV FWHM was achieved.
Figure 1(a) shows an -particle spectrum measured at the first detector station. The 7581(4) and 7535(4)keV  lines were clearly observed which correspond to the  transitions from 240Cf to the ground- and thefirst 2+ state in 236Cm, respectively. The half-life of 40.3(9) s was derived from the decay curve of these events as depicted in Fig. 2. These values are more accurate than the literature values of 7590(10) keV and1.06(15) min [2]. The energy difference between the 7581 and 7535 keV  transitions was deduced to be
46.6(4) keV (preliminary), leading to E(2+) = 47.4(4) keV in 236Cm. The 7328(4) keV  line was attributed
to the  decay of 241Cf, and the half-life of 141(11) s was derived from its decay curve. The literature
values of  energy and half-life of 241Cf are 7335(5) keV and 3.78(70) min, respectively [2]. The present
results revised these data more accurately.
Figure 1(b) shows a sum of -particle spectra measured at the 4th, 5th, and 6th detector stations. In thisspectrum, we found unknown  transitions of 6947(5) and 6894(5) keV which probably originate from the decay of 236Cm, the daughter nucleus of 240Cf. The 236Cm is a new isotope whose decay properties have1Japan Atomic Energy Agency- 21 -

JAEA-Review 2010-056
never been reported. The half-life of these  events was about 10 min though it has a large uncertainty.
From the -energy difference, E(2+) of 232Pu was deduced to be 54(4) keV (preliminary). These results
revealed that E(2+) in Cm and Pu isotopes increases with decreasing neutron number, reflecting the

214

Po

Cf
240

7581

7535 240 Cf

242

Cf

Po
211m

10 2

060 s7328 241 Cf

Ra
214

212

(a)

211

Counts / 2.5 keV

10 3

Ra
Ra

decreasing deformation towards the neutron closed shell at N = 126.

10 1

Po
214

Cf
Cf

240

Cf

241

242

Cf

Rn
218

6947

180360 s
240

10 1

Cm

(b)

236

10 2

6894 236 Cm

Counts / 2.5 keV

10 0

10 0
6800

7000

7200
7400
Energy (keV)

7600

Fig. 1 (a) -particle spectrum measured at the first detector station. (b) Sum of -particle spectra
measured at the 4th, 5th, and 6th detector stations. Ra isotopes and 211mPo are produced in thereactions with Pb impurity included in the target.

103

240

Cf

Counts counts
10

2

101

T1/2 = 40.3 ± 0.9 s
100

0

100

200
Time (s)300

Fig. 2 Decay curve of  particles of 240Cf.
Reference[1] Y. Nagame et al., J. Nucl. Radiochem. Sci. 3 (2002) 85-88.
[2] R. J. Silva et al., Phys. Rev. C 2 (1970) 1948-1951.

- 22 -

JAEA-Review 2010-056

2.4

Signature splitting property in the one-quasiparticle bands of 173W
Y.H. Zhang 1 , X.H. Zhou2, M. Oshima 2 , M. Koizumi2, Y. Toh2, A. Kimura2,
H. Harada2, K. Furutaka2, F. Kitatani2, S. Nakamura2, Y. Hatsukawa2, M. Ohta2,
K. Hara2, T. Kin2 and J. Meng 3

An in-beam -spectroscopy of 173W has been studied in the Japan Atomic Energy Agency (JAEA) via the150
Nd(28Si,5n)173W reaction. The purpose of this experiment is to search for low-spin signature inversion
in the 5/2[512] band of 173W, which could be the reason of signature inversion recently observed in the1/2[541]5/2[512] band of odd-odd 174Re [1]. The high-spin states of 173W was investigated by Walker
et al., and a level scheme up to 31/2 had been reported for the 5/2[512] band [2]. In this experiment, a
28
Si beam of 1 pnA was provided by the tandem accelerator in JAEA. The target was an enriched 150Nd
oxidized powder of 2.0 mg/cm2 thick evaporated onto a gold metallic foil of 7.8 mg/cm2 in thickness. The
GEMINI-II [3] -ray detector array was employed to detect the in-beam  rays. x-, --t coincidences havebeen measured at 135-, and 140-MeV beam energies. A total of 1.7108 - coincidence events was
accumulated. These coincidence events were sorted into a symmetric and a non-symmetric (DCO sorting)matrices for off-line analysis.

Fig. 1 Level scheme of 173W deduced from the present work
Fig. 1 presents the level scheme of 173W deduced from the present work. In comparison with the previous
study [2], three bands have been extended up to high-spin states.
1

Institute of Modern Physics, Chinese Academy of Sciences
Japan Atomic Energy Agency (JAEA)
3Peking University
2- 23 -

JAEA-Review 2010-056
The signature splitting, defined as S(I) = E(I+1) E(I1)1/2 [E(I+1) E(I) + E(I1) E(I2)], is plottedin Fig 2 for the 5/2[512], i13/2 bands in 173W, and the 1/2[541]5/2[512] band in 174Re. One can see
in this figure that the i13/2 band exhibits a normal signature splitting, i.e., the favored signature (f )levels keep lower-lying along the whole band. Usually the signature splitting for this band is small at lower
spins, and it increases significantly at higher-spin states but keeping the is the signature quantum
number and I Mod 2) I=2 sequence lower in energy along the whole band. However, a close inspectionof the 5/2[512] band shown in Fig. 2 reveals that it is the signature branch that lies lower rather thanthe sequence at lower-spin states. At higher-spin states beyond I33/2, the normal signature
splitting is restored, say, with the  signature branch lying lower in energy. This phenomenon has
been observed in a number of 2-quasiparticle bands in odd-odd nuclei and has been referred to as signature
inversion or anomalous signature splitting.

Fig. 2 Plot of signature splitting S(I) against spin I for the three bands in 173W and 174Re
An important issue from present investigations may be the observation of low-spin signature inversion inthe 5/2[512] band of 173W. As is well known, the low-spin signature inversion has been observed in a
number of two-quasiparticle bands of odd-odd nuclei in this mass region. The inversion phenomenon has
also been observed in some odd-Z nuclei, but in these cases, signature inversion occurs at higher rotationalfrequencies beyond bandcrossing [4].
The present result provides an interesting testing ground for different theoretical approaches. For instance,
one may certainly disregard the effects of proton-neutron residual interactions in such one-quasiparticle
bands. Furthermore, the nuclear triaxiality should be of less importance for the inversion phenomenon sincethe i13/2 band in the same nucleus has normal signature splitting. Given the fact that the 5/2[512] and5/2[523] Nilsson orbitals have strong interactions, the configuration mixing may play an important role
for the low-spin signature inversion in the 5/2[512] band of 173W. Similarly, the inversion phenomenon inthe 1/2[541]5/2[512] band of 174Re could be associated also with the configuration mixing. This is inneed of further theoretical investigations.
References[1] Y. H. Zhang et al., CHIN. PHYS. LETT., 24 (2007) 1203-1206.
[2] P. M. Walker et al., J. Phys. (London), G4 (1978) 1655-1677.
[3] M. Oshima et al., J. Radioanal. Nucl. Chem., 278 (2008) 257-262.
[4] A. Ikeda et al., Phys. Rev., C42 (1990) 149-166.

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JAEA-Review 2010-056

2.5Structure evolution of the yrast band in 101Pd

X. H. Zhou1, H. B. Zhou1,Y. H. Zhang1, Y. Zheng1, M. L. Liu1, N. T. Zhang1, Y. D. Fang1,
M. Oshima2, Y. Toh2, M. Koizumi2, Y. Hatsukawa2 and M. Sugawara3

Nuclear shape evolution is a major theme in nuclear structure research. This evolution is intimately related
to the mechanisms by which atomic nuclei generate angular momentum. The transitional nuclei in A100
mass region, which are located below the closed shell Z=50, have attracted a lot of experimental andtheoretical interests. The experimental study led to the identification of the phase transition from vibrational
structure to rotational structure along the yrast line in the even-even nuclei while increasing spin [1]. For an
odd-A nuclide in this mass region, its high-spin states may be formed by coupling weakly the valence
nucleon to the respective core excitations. Therefore, the odd-A nuclei would be expected to exhibit phaseevolution as their neighboring even-even nuclei. It is our primary aim to extend the level scheme of 101Pd tohigh-spin states, and to study the structure evolution phenomenon.
High spin states in 101Pd have been investigated using the 76Ge (28Si, 3n) reaction at beam energies of 85
and 95 MeV. The 28Si beam was provided by the tandem accelerator at the Japan Atomic Energy Agency(JAEA). The target was an isotopically enriched 76Ge metallic foil of 2.0 mg/cm2 thickness with an 8.0
mg/cm2 Pb backing. The GEMINI-II [2] -ray detector array was employed to detect the in-beam  rays. A
total of 2.3×108 coincidence events were recorded. After accurate gain matching, the coincidence eventswere sorted into symmetric and ADO matrices for off-line analysis. Based on the analysis of -coincidence relationships, -ray relative intensities, and energy sum, a level scheme of 101Pd has been
established and presented in Fig. 1(a). As compared with the previous work [3, 4], we extended band 1
from 29/2+ up to 33/2+. Band 3 has been reported up to 35/2− in Ref.[3]. In the present work, it was
confirmed and extended with two additional levels up to excitation energy of 9.04 MeV. We have identified
a new cascade labeled as structure 2, consisting of 526-, 920-, 902-, and 1028-keV transitions.
To reveal the structure evolution in the yrast band of 101Pd, we plotted the RE-GOS = Eγ (I → I − 2)/I versus I
trajectory, so-called E-GOS curve, which is sensitive to a transition between vibrational and rotational
states [1]. For a vibrator, this ratio gradually diminishes to zero as the spin increases, while for an axially2symmetric rotor it approaches a constant, 4[  /(2J )]. Here, J is the static moment of inertia. In Fig.1 (b),we compare the E-GOS curves for the yrast lines of 100-102Pd. The behavior of the E-GOS curve of 101Pd isin good agreement with the assumption that the low-spin yrast states show a vibrational structure, whereas
the higher-spin states have a rotational character.

1

Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
3
Chiba Institute of Technology, Narashino, Chiba 275-0023, Japan2- 25 -

JAEA-Review 2010-056

Fig. 1 (a) Level scheme of 101Pd deduced from the present work. (b) E-GOS curve for the ground-stateband of 101Pd. The E-GOS curves for the ground-state bands of 100,102Pd are also shown for comparison.

References[1] P. H. Regan et al., Phys. Rev. Lett., 90 (2003) 152502.
[2] M. Oshima et al., J. Radioanal. Nucl. Chem., 278 (2008) 257-262.
[3] R. Popli et al., Phys. Rev., C22 (1980) 1121-1125.
[4] P. C. Simms et al., Phys. Rev., C9 (1974) 684-698.

- 26 -

JAEA-Review 2010-056

2.6

Proton resonance elastic scattering of 68Zn
with thick target inverse kinematics method

N. Imai 1 , Y. Hirayama1, H. Ishiyama1, S.C. Jeong1, H. Miyatake1, Y.X. Watanabe1, H. Makii2,
S. Mitsuoka2, D. Nagae2, I. Nishinaka2, K. Nishio2 and K. Yamaguchi3

When much more neutrons are added onto a nucleus than usual, how does the nuclear structure change ?
The basic question can be answered by investigating the single particle structures of neutron-rich nuclei.
We proposed measurement of isobaric analog resonances (IARs) to study single particle states of such
unstable nuclei. Owing to the isospin symmetry of nuclear force, the neutron wave functions of a nucleus
A+1

Z are identical with proton wave functions appeared in the high excitation energies in the daughter

nucleus A+1(Z+1), called “isobaric analog states”. The analog states can be accessed by the proton elastic
scattering of AZ [1]. When we measure the excitation function of differential cross sections at a given angle,
the cross section at the excitation energy corresponding to the analog state will be enhanced as a resonance.
By analyzing the shape of the excitation function, we can determine the wave function.
In this study, we measured the excitation function of proton elastic scattering at 180 degrees in the center ofmass frame by employing the thick target inverse kinematics method. The scattering angle corresponds to 0
degree in the laboratory frame. In the case of the elastic scattering at 0 degree in the lab frame, which issensitive to the resonances, the energy of recoil proton reaches 4 times higher than the c.m energy (Ec.m).
Thus, even if the single particle levels are crowded, it is much easier to separate them. By using the thicktarget, a wide range of the excitation function of the elastic scattering can be measured with a beam of a
fixed incident energy corresponding to the highest end of the range. When a resonance state has a proton
width as large as several keV, it can be observed in the excitation function as an interference of potential
and resonance scattering. The resonance energy, width, and spin-parity (J) can be extracted from theexcitation function by employing R-matrix analysis.
As the first test of measuring the isobaric analog states in medium nuclei using the inverse kinematics
proton elastic scattering, we searched for the isobaric analog states of 69Zn with 68Zn beam with a proton
target. The analog states were well studied with the normal kinematic condition [2].
The experiment was performed at JAEA tandem accelerator facility. A 68Zn beam of 5.5 MeV/nucleon was
accelerated by tandem accelerator and superconducting booster linac. The beam of around several epA was
focused on a 3 mg/cm2 thick polyethylene (CH2) target. Downstream of the CH2 target, 10 mg/cm2 thickcarbon was placed to stop the beam. In order to evaluate the contribution from carbon in CH2 target, weremoved the CH2 and measured the resonance elastic scattering only with carbon foil. The energies ofrecoil protons were measured by the three layers of silicon semiconductors (SSDs) of 50 x 50 mm2 which
1High Energy Accelerator Research Organization (KEK)
Japan Atomic Energy Agency (JAEA)
3
University of Tsukuba
2- 27 -

Esum (MeV)

JAEA-Review 2010-056
20
18

t

16

4

10

d

14

103

12
10

p

102

8
10

6
4

1

2
0

-1

0

2

4

6

8

10
ΔE (MeV)10

Fig. 1 Energy correlation between E and E.

Fig. 2 Excitation function of proton elastic scattering

Indexes p, d, t indicate loci for protons, deuterons,

around Ec.m.=5 MeV. Red line indicates the best fitted

and tritons, respectively.

R-matrix curve for l = 0.

were located 50 cm downstream of the target. The thickness of each SSD was 300 m. The highest energyof recoil proton was calculated to be around 20 MeV. To completely stop the proton, we needed a 3 mm
thick SSDs. Instead of using such thick SSDs in the experiment, we put a 1.5 mm thick aluminum plate justdownstream the SSDs and compensated the energy loss in the aluminum.
Figure 1 shows the correlation between the energy deposit in the first layer SSD (E) and the sum of theenergy deposits in all SSDs (Esum). In addition to protons, deuterons and tritons were clearly observed.
The Esum of protons was converted to the excitation function by considering the detection efficiency andconversion function of experimental energy deposits to the reaction energy in the center of mass frame.
Both parameters were obtained by performing Monte Carlo simulations.
The resultant excitation function is presented in Fig.2, representing a resonance around Ec.m.= 5 MeV. When
we searched for 2 minimum by changing p with the assumed angular momentum l = 0. The best fitted
curve was obtained with p = 19 +/- 5 keV, which reproduced the reference value of p = 20 keV [2]. Notethat the parameters were not converged with l = 1 and 2, ruling out those angular momenta.
In summary, we applied the proton resonance elastic scattering with thick target inverse kinematics method
to obtain the single particle structure of 69Zn. The proton width obtained in the present experiment
reprouced the reference value, demonstrating that the proton resonance elastic scattering in inverse
kinematics for IAR is a powerful tool for studying neutron single particle states in neutron-rich nuclei.
References[1] V.Z. Goldberg, in ENAM98, edited by B.M. Sherrill, D.J. Morrisey, and C.N. Davids, AIP Conf. Proc.
No.455, p319.
[2] W.S. Steiner, et al., Phys. Rev., C4 (1971) 1684.

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JAEA-Review 2010-056

2.7Development of laser spectroscopy for radioactive isotopes
in the rhenium region
H. Iimura 1 , M. Koizumi1, M. Miyabe1, M. Oba1 and I. Wakaida1

Laser spectroscopy of the hyper-fine structures (HFS) and isotope shifts (IS) in atomic spectra has been
providing much information on the studies of nuclear structure since nuclear moments and nuclear charge
radii determined from the HFS and IS, respectively, strongly reflect nucleon motions in a nucleus andnuclear shapes. Neutron-deficient nuclei in the rhenium region (Z~75) have been attracting much interest
because axially asymmetric shapes are predicted theoretically for them [1]. However, the laser
spectroscopy for these isotopes is very scarce because elements in this region are refractory and are difficult
to be evaporated from a sample. In order to perform the laser spectroscopy for these isotopes, we aredeveloping two new techniques, namely off-line laser-ablation laser spectroscopy for relatively long-lived
isotopes and on-line gas cell laser spectroscopy for short-lived ones. Following is our recent progress indeveloping these techniques.
Laser ablation is a promising technique for producing an atomic beam for laser spectroscopy of radioactive
isotopes of refractory elements not accessible via the normal resistance heating method. A setup of thelaser-ablation laser spectroscopy is schematically shown in Fig. 1. A beam from a pulsed Nd:YAG laser(1.06 m in wave length) was focused on the target of metallic disk of natural rhenium in vacuum or in a
few hPa of ambient Ar gas. The power density of the pulsed Nd:YAG laser was about 1 J/cm2 on the target,
which was high enough to ablate rhenium metal. The repetition rate of the Nd:YAG laser was 10 Hz andthe pulse width was 6 ns. Another CW Nd:YAG laser (0.53 m) was used to pump a tunable ring dye laser.
This dye-laser beam was introduced perpendicularly to the pulsed Nd:YAG laser beam so that it irradiatedthe rhenium atoms evaporated from the target by laser ablation. The distance between the dye-laser beamand the surface of the target was 1 mm. Laser-induced fluorescence was collected by a lens system andtransferred to a photomultipliertube through an optical fiber. A
monochromator was used to

Pulsed YAG
laser

observe the fluorescence of a

Photomultiplier
tube
Lens

specific de-excitation transition.
In

order

to

reduceAr gasbackground light emitted fromthe ablation plume, appropriate

CW YAG
laser

Ring dyelasertime gate was set in counting
the photomultiplier tube signals.
The

resonancepeaks

TargetPhotomultiplier
tube

were

observed by scanning the1

Monochromator

theFig. 1 Setup of the laser-ablation laser spectroscopy.

Japan Atomic Energy Agency (JAEA)- 29 -

JAEA-Review 2010-056

frequency of the tunable laser. The width of the resonance peaks was about 1 GHz which is approximately
one order better than our previous value obtained by using a broad band dye laser pumped by a pulsed
XeCl excimer laser. Although the line width we obtained is narrow enough to resolve the isotope shifts, thesensitivity of this apparatus is still insufficient for the measurement of minute amount of radioactive
isotopes. Presently we are working on improving the sensitivity so as to measure long-lived isotopes suchas 186mRe (T1/2=2105 y) which we have already produced by using the JAEA-Tokai tandem accelerator [2].
Another apparatus we are developing for the laser spectroscopy of refractory elements is an on-line gas cellin which the reaction products recoiling out of the target are stopped. These reaction products are thenirradiated with a laser beam before diffusing through the gas to the wall of the gas cell. Laser-induced
fluorescence is collected on a photomultiplier tube by using a mirror and lenses. The gas cell for thisexperiment has been set at a beam line of the JAEA-Tokai tandem accelerator. Prior to the studies ofradioactive isotopes, we are working with stable isotopes to optimize the sensitivity of the apparatus. In
order to simulate the tungsten isotopes (Z=74) produced by heavy-ion fusion reactions, a beam of stable
184

W was accelerated to 100 MeV by using the tandem accelerator and injected into the gas cell without

setting the target. After passing through two 2.5 m Ni foils which isolate the gas cell from the accelerator
beam line, energy of the tungsten beam became the same as that of the reaction-produced isotopes. The
pressure of Ar gas was set at 19 hPa to stop 184W at the center of the cell. Since the production rate ofradioactive isotopes by heavy-ion fusion reactions is expected to be less than 105 atoms/s, it is important to
reduce background light to observe the laser-induced fluorescence signals. The largest part of the
background is the light coming from the collisions between the gas and the accelerator beam. Since thereaction products are expected to remain in the gas for a few seconds, it may be possible to reduce thisbackground by chopping the accelerator ion beam and counting the laser-induced fluorescence signals only
when the ion beam is off. We examined this method by chopping the 184W ion beam at the repetition rate of
10 Hz. As a result, the background was suppressed more than one order, demonstrating the effectiveness of
this method. Additional methods, such as removing impurities in the gas by cooling the wall of the cell, arein progress to further improve the sensitivity of the apparatus. After these improvements, on-line laser
spectroscopy of short-lived tungsten isotopes is planned.

References[1] P. Möller et al., At. Data Nucl. Data Tables, 59 (1995) 185-381.
[2] H. Iimura et al., J. Phys. Soc. Jpn., 77 (2008) 025004.

- 30 -

JAEA-Review 2010-056

2.8Development of Si ΔE-E telescope using an annular-type E detector for in-beam
γ-ray spectroscopy
R. Takahashi 1,2, T. Ishii 2 , H. Makii2, M. Asai2, Y. Wakabayashi2, D. Nagae3, K. Tsukada2,
A. Toyoshima2, M. Matsuda2, A. Makishima4, T. Shizuma2, T. Kohno5 and M. Ogawa6

We have developed a spectroscopic method of combining particle and γ-ray measurements using Si ΔE-E
telescopes for heavy-ion transfer reactions [1]. This method was so far successfully applied to measuring
in-beam γ-rays of actinide nuclei such as 245,246Pu (Z = 94), 249,250Cm (Z = 96), and 248,250,252Cf (Z = 98)[2-5]. In these experiments, the excitation energies of the residual nuclei are obtained by the kinematics
analyses of scattered particles. However, the excitation energy has an ambiguity of approximately 2 MeV
owing to the covering angle (±10°) of the Si ΔE-E telescope. In order to improve the ambiguity, we havedeveloped a new Si ΔE-E telescope consisting of an annular-type E detector and four ΔE detectors (Fig. 1)
to measure the scattering angles with higher accuracy.
The Si detector (designed by Micron SemiconductorLtd) has an annular active-area whose inside
diameter is 47.9 mm and outside diameter is 96.1 mm.
This active area is divided into 16 lanes annularly. By
setting this telescope 4 cm apart from the target, we
can measure scattering angles with the accuracy ofapproximately ±0.5°. Energy resolution using thistelescope was tested using a 0.4 mg/cm2 thick 197Au
target which was vacuum-evaporated onto a 0.54
mg/cm2 aluminum foil and a 144 MeV 16O beamadjusted to be 1.4 mm in diameter.
Fig. 2 shows an energy spectrum of the 16O + 197Au
elastic scattering, which is obtained by the sum ofenergies of a ΔE detector and the second annular lane(from the inside) of the E detector. The energy

Fig. 1

Si Δ E-E telescope consisting of anannular-type E detector and four ΔE detectors.

resolution of the peak is 0.7 MeV (0.5%) [FWHM]. It was found that the improved ΔE-E telescope hasenough resolution to be used for in-beam γ-ray spectroscopy. We have applied this ΔE-E telescope toin-beam γ-ray spectroscopy of 249Cm using the (16O,15O) transfer reaction.
1

Tokyo University of Science
Japan Atomic Energy Agency (JAEA)
3
University of Tsukuba
4
National Defense Medical College
5Tokyo Institute of Technology
6
Komazawa University
2- 31 -

JAEA-Review 2010-056[×10 5 ]1
0.7MeV [FWHM]Counts

0.8
0.6
0.4
0.2
120

Fig. 2130
140
Energy[MeV]150

Energy spectrum of the 16O + 197Au elastic scattering. This spectrum was obtained by the sumof energies of a ΔE detector and the second annular lane (from the inside) of the E detector.
References[1] T. Ishii et al., Phys. Rev., C72 (2005) 021301(R) (1-5).
[2] T. Ishii et al., J. Phys. Soc. Jpn, 75 (2006) 043201 (1-4).
[3] H. Makii et al., Phys. Rev., C76 (2007) 061301(R) (1-5).
[4] T. Ishii et al., Phys. Rev., C78 (2008) 054309 (1-11).
[5] R. Takahashi et al., Phys. Rev., C81 (2010) 057303 (1-4).

- 32 -

JAEA-Review 2010-056

2.9

Coulomb excitation of 130Ba at 1.1 MeV/nucleon

N. Imai1, Y. Hirayama1, H. Ishiyama1, S.C. Jeong1, H. Miyatake1, Y.X. Watanabe1, H. Makii2,
S. Mitsuoka2, I. Nishinaka2, K. Nishio2 and Y. Wakabayashi2

Barium isotopes are located in an island of octupole deformation. The B(E2) and B(E1) values in these
nuclei give us crucial information on the octupole correlations to the dipole or quadrupole moments innuclei. A recent lifetime measurement of the first 2+ (2+1) state of 142Ba gave a B(E2) value inconsistent
with the past experimental data [1]. Up to date, the B(E2) values of 142Ba have been deduced using the
lifetime measurements of the 2+1 state produced in the spontaneous fission of 252Cf. The inconsistency
among the past data can be attributed to how to take into account the effects of cascade transitions andrecoil velocities of fission products. Instead of lifetime measurement, we proposed to use the Coulomb
excitation of 142Ba by employing Tokai Radioactive Accelerator Complex (TRIAC) [2]. TRIAC canaccelerate radioactive isotopes extracted by JAEA ISOL upto 1.1 MeV/nucleon, which is far below the
Coulomb barrier. Thus, the cascade transition is negligible since the probability of multi-step excitation
should be very small.
As a test of the whole experimental system including charge-breeding electron cyclotron resonance ion
source called as KEKCB [3], we performed an experiment of Coulomb excitation with a stable 130Ba beamof 1.1 MeV/nucleon. The energy of 2+1 state of 130Ba is 359 keV, which is close to the 357 keV for 142Ba.
The present experiment simulates the measurement of 142Ba.
A 130Ba1+ beam was supplied by JAEA ISOL using the enriched BaCO3. Typical beam intensity was about
30 enA. The beam was injected into the KEKCB for charge-breeding the singly charged ions 130Ba1+ to
multi-charged ones 130Ba19+. The charge breeding efficiency achieved was around 1%. The 130Ba19+ beam
was transported to two linear accelerators, split-coaxial radiofrequency quadrupole (SCRFQ) andinter-digital H (IH) linacs. Using the two linacs, the beams energy was increased to 1.1 MeV/nucleon.
At the final focal plane of TRIAC, a secondary target of 3 m thick natV was placed and irradiated by thebeam. Three NaI(Tl) detectors of 9 x 9 x 18 cm3 were placed to detect the de-excitation  rays from theexcited 130Ba around the target. The NaI(Tl)s were mounted in the 2 cm thick lead box to suppress the
background  rays or X rays. To measure the recoiled particles, an annular type SSD of a large solid angle
was placed 18 cm downstream of the target. The detector covered from 12 to 24 degrees in the laboratory
frame, which corresponds to angles from 48 to 160 degrees in the center of mass frame. While 92% of
inelastic scattering channel can be measured by the detector, the elastic channel can be reduced to be
0.016 % of total cross section.

1
2

High Energy Accelerator Research Organization (KEK)
Japan Atomic Energy Agency (JAEA)- 33 -

JAEA-Review 2010-056
Figure 1 (a) shows the two -ray energy
spectra measured by a NaI(Tl) detector
with different timing gates. The solid line
indicates  rays which were coincident
with the SSD, while the dashed line
represents the accidentally coincident 
rays. The  ray spectrum obtained bysubtracting the accidental ones from thecoincident ones is shown in Fig.1 (b),presenting that only a 360 keV line wereclearly observed.
The beam development of 142Ba was also
performed

independently.

The

beam

intensity is expected to be several 103
particles/s at the secondary target. The
measurement of B(E2) value of the 2+1
state of 142Ba is scheduled in this summer.
Fig. 1 (a)  ray energy spectra coincident with SSD (solidline) and accidentally coincident with SSD (dashed line).
(b)  ray energy spectrum obtained by subtracting theaccidental  rays.

References[1] D.C. Biswas, et al., Phys. Rev., C71 (2005) 011301.
[2] H. Miyatake et al., Nucl. Instrum. Methods Phys. Res., B204 (2003) 420-427.
[3] S.C. Jeong, et al., Nucl. Instrum. Methods Phys. Res., B266 (2008) 4411-4414.

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JAEA-Review 2010-056

2.10

Search for highly excited 11Be states in 9Li+d reactions

T. Teranishi 1 , H. Ishiyama 2 , H. Miyatake2, S.C. Jeong2, Y.X. Watanabe2, N. Imai2, Y. Hirayama2,
A. Osa3, T.K Sato3, S. Mitsuoka3, K. Nishio3, M. Matsuda3, H. Makii3, Y. Wakabayashi3,
T. Hashimoto4, Y. Ito5, Y. Kenmoku5 and K. Yamaguchi6

An excited level at 18.2 MeV in 11Be has been suggested from observations of beta-delayed deuteron, triton,and  emissions in 11Li beta decay experiments [1]. This level is above and close to the 9Li+d threshold at
17.9 MeV and possibly enhances the beta delayed deuteron emission probabilities [2] (Fig. 1). This level isalso a candidate of a “halo analog state” of 11Li, which is populated by a GT transition of the two halo
neutrons in 11Li, namely 11Li (9Li+2n)  11Be* (9Li+d) [3]. Clear determination of the energy, width, andspin-parity may be therefore useful for studying the GT transitions of 11Li and its halo structure. However
the signature of the level was not so clear in the beta decay experiments: the energy and width of the level
were deduced from fitting of a spectrum containing unresolved deuterons and tritons without any sharp
peak, and also from fitting of an unresolved 4,6He spectrum in the decay 11Li()11Be*  6He++n, which
did not also show any peak of the level because of the three body decay. Moreover, a recent observation ofbeta delayed deuterons did not indicate any resonance signature [4]. Further experimental investigation
with a different approach is necessary.

20.68
11Li



18.15
17.916
9Li+d
8Li+t, 2+3n,
6He++n,0
11Be

9Be+2n, 10Be+n

Fig. 1 -delayed particle emission from 11Li via the 18.2 MeV level in 11Be.
In the present experiment we have studied 9Li+d reactions to search for a resonance signature attributed to
the 18.2 MeV level. We measured deuteron, triton,  spectra from 9Li+d elastic scattering, 9Li(d,t), and9Li(d,) reactions, respectively. The 9Li+d reaction experiment was performed at TRIAC (Tokai

Radioactive Ion Accelerator Complex). A primary beam of 7Li at 70 MeV from the JAEA tandem
accelerator bombarded an ISOL target of BN. Secondary 9Li ions extracted from the ISOL target wereaccelerated by TRIAC up to 0.85 MeV/u. Fig. 2 shows the experimental setup for the 9Li+d reactions. The
1

Kyushu University
High Energy Accelerator Research Organization (KEK)3Japan Atomic Energy Agency (JAEA)
4
Center for Nuclear Study (CNS), the University of Tokyo
5
Osaka University
6
University of Tsukuba
2- 35 -

JAEA-Review 2010-056

secondary beam ions were counted on an event-by-event basis using an MCP detector with a 0.1 mg/cm2
Mylar foil. After passing through the MCP detector, the 9Li beam bombarded a (CD2)n target of 2.3 mg/cm2
with an average beam intensity of approximately 3104 particles/s. To deduce the excitation functions of
9

Li+d scattering, 9Li(d,t), and 9Li(d,) reactions, we utilized a thick target method in inverse kinematics(TTIK), where the target thickness was chosen to be thick enough to stop most of the incident 9Li ions in
the target. The recoil deuteron, triton, and  particles suffered relatively small energy losses in the targetand detected by a Si detector array (SDA) located 26 cm downstream of the target with its center at 0°.
SDA consisted of 3×3 Si detectors, each of which was 300 m thick and had a 28×28 mm2 sensitive area.
Particle identification was made using time-of-flight (TOF) information from MCP to SDA and energy (E)information of SDA. Fig. 3 shows an example of the measured TOF-E spectrum. There was a backgroundcomponent below 2 MeV, which was due to accidental  particles from the beta decay of 9Li. The timing
distribution of the accidental  particles was essentially uniform and their energy distribution could be
easily estimated. Then, the accidental background component was subtracted from the deuteron, triton, and spectra.
Though analysis is in progress, a preliminary result of the 9Li+d spectrum contains no sharp peak but showsmonotonically increasing cross sections toward the low energy side. The low energy limit of the spectrum
due to the detector threshold was E ~ 0.6 MeV (Ec.m. ~ 0.3 MeV), which was unfortunately almost the sameas the expected resonance energy for the 18.2 MeV level. This means that only the upper half of theresonance shape might be observed. A possibility of resonance contribution to the spectral shape above Ec.m.
= 0.3 MeV will be examined by utilizing R-matrix analysis. We will also analyze the triton and  spectraon the same R-matrix basis by assuming some resonance contributions.

Fig. 2 Experimental setup for 9Li+d reactions.

Fig. 3 E-TOF spectrum for recoil particles.

References[1] M.J.G. Borge et al., Nucl. Phys., A613 (1997) 199 and references therein.
[2] D. Baye et al., Phys. Rev., C74 (2006) 064302 and references therein.
[3] M.V. Zhukov et al., Phys. Rev. C52 (1995) 2461.
[4] R. Raabe et al., Phys. Rev. Lett., 101 (2008) 212501.

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JAEA-Review 2010-056

CHAPTER 3
Nuclear Reaction

3.1

Measurement of fission cross-sections in the reactions of 34,36S + 204,206,208Pb

3.2

Coulomb barrier distribution of quasi-elastic backscattering in 64Ni + 238U

3.3

Measurement of fission fragment mass distribution in the reaction of 40Ar + 238U

3.4

Fission properties of the neutron-deficient nucleus 180Hg
produced in heavy ion fusion reactions

3.5

Fission fragment anisotropy in heavy-ion-induced fission of actinides

3.6

Search for the new isotope 220Pu produced in the fusion reaction 82Kr + 140Ce

3.7

Study of 218U region near N=126 closed shell

3.8

Production of 256Lr with the 249,250,251Cf(11B, xn) and 243Am(18O, 5n) reactions

3.9

Measurement of fission probability of 240Pu
produced by nucleon transfer reaction 238U(18O, 16O)240U

3.10 Development of a measurement system for (n,) cross sections
using the surrogate reaction methods
3.11 High energy alpha particles emitted from nuclear reaction
3.12 Development of GEM-MSTPC for measurement of the 8Li(, n)11B reaction- 37 -

This is a blank page.

JAEA-Review 2010-056

3.1

Measurement of fission cross-sections in the reactions of 34,36S + 204,206,208Pb

J. Khuyagbaatar 1 , D. Ackerman1, M. Block1, S. Heinz1, F.P. Heβberger1, S. Hofmann1, H. Ikezoe2,
B. Kindler1, B. Lommel1, H. Makii2, S. Mitsuoka2, I. Nishinaka2, K. Nishio2, Y. Wakabayashi2 and S. Yan3

Measurements of the decay properties and the structures of very heavy nuclei are important to understandthe limit of stability of nucleus. The most successful reaction for the production of heavy nuclei is fusion of
two colliding nuclei forming an excited compound nucleus which de-excites by evaporation of neutrons.
However, the cross-sections for the production of heavier nuclei are strongly decreasing with increasing
number of protons. Thus, the accuracy for investigating nuclear structures for heavy nuclei is limited byproduction rates. Selection of fusion-evaporation reactions having highest cross-sections is important.
(i) The cross-sections of the fusion-evaporation reactions of 36S+206-208Pb and 34S+208Pb which produce theneutron-deficient isotopes of Cf were measured recently at SHIP [2]. The cross-sections for the 2n and 3n
evaporation channels for the 36S+206-208Pb reactions were on the order of a few hundred nanobarn which are
unexpectedly higher than the values in [3] and calculated values by HIVAP code [4]. Further thecomparison of the cross-sections of 2n and 3n channels from fusion reactions 36S+206Pb and 34S+208Pb
leading to the compound nucleus 242Cf, reveals significant differences which can not be explained bydifferences of the reaction Q-values alone. Additional effects could also be the reason for the different
cross-sections.
(ii) The fusion reaction of colliding nuclei with proton and neutron numbers close to magic andsemi-magic numbers are characterized by a steep falloff in the capture cross-sections at energies below the
Coulomb barrier [1]. Combinations of 36S and 34S projectiles with various lead-isotope targets at absent
deformation effect are very suitable for the study of the influence of the nuclear structure of 36S and 34S(semi-magic) nuclei on the fusion reaction.
The purpose of this experiment was to investigate the entrance channel effects which include subjects of(i) and (ii) by measuring the fission fragments from the 36S+Pb and 34S+Pb reactions. Here, we present
preliminary results on the capture cross-sections which are directly connected to (ii).
The experiment was performed at the tandem accelerator of JAEA. Isotopically enriched material of 40%
and 60% for 36S and 34S, respectively, was used for the negative ion source. The beams were accelerated up
to energies of 200 MeV and the average beam current was 3 pnA. Pure metallic Pb targets with thicknessesof 100 µg/cm2 were prepared at the target laboratory of GSI. The targets were prepared by evaporatingisotopically enriched (≥99%) 204,206,208Pb materials on carbon backing foils with average thicknesses of 40µg/cm2. The opposite side of the targets was covered by a 10 µg/cm2 carbon layer. The targets were
mounted at an angle of 45° to the beam axis with the thinner carbon layer in the beam direction. Two
Multi-Wire-Proportional-Counters (MWPCs) were used to detect the fission fragments in coincidence. The
beam dose was deduced using the number of elastically scattered particles at an angle of 26.5° relative tothe beam axis and with a solid angle of 1.96 msr. The experimental setup and the analysis of the fission
1

GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
Japan Atomic Energy Agency (JAEA)
3
China Institute of Atomic Energy (CIAE)
2- 39 -

JAEA-Review 2010-056

data were the same as described in [5].
Preliminary results of the capture cross-sections are shown in fig. 1 as a function of the center-of-massenergy. The behavior of the excitation functions of 36S+204,206,208Pb reactions is similar and it ischaracterized by a steep falloff of cross-sections at low energies (same for 34S). This indicates that thechange of nuclear structures of the proton magic target nuclei 204,206,208Pb has not much influence on theentrance channel. However, the slopes of the falloff are different in the case of 36S and 34S, whereas the
behavior of the cross-sections at energies around and above the barrier is similar. The cross-sections
calculated using the CCFULL code [6] are also plotted in fig. 1. The dotted curves represent the calculated
results from a one-dimensional barrier penetration model without coupling to excited states. These
calculations cannot describe the cross-sections at energies below the Coulomb barriers. The cross-sections
down to the lowest energies are well described by the calculations where coupling of the first 2+ and 3states in the projectile and the target nuclei, respectively, were included (solid curves). These results showthat the enhancement of the fusion process at sub-barrier energies is higher for 34S than for 36S. This is dueto the strong couplings to the 2+ state in 34S which is located at lower excitation energy of 2.127 MeV thanthe couplings to the 36S state of 3.291 MeV.

Fig. 1 Cross-sections deduced from the measured fission events from the 36S+Pb and 34S+Pb reactions
as a function of the center-of-mass energy. Curves represent the calculated cross-sections (see text).
Radius(r0), diffuseness (a) and corresponding fusion barrier (Bfus ) are given for each reaction.
References

References[1] C.L. Jiang et al., Phys. Lett., B640 (2006) 18 and reference therein.
[2] J. Khuyagbaatar et al., to be published.
[3] Yu. Lazarev et al., Nucl. Phys., A588 (1995) 501.
[4] W. Reisdorf and M. Schaedel, Z.Phys., A343 (1992) 47.
[5] K. Nishio et al., Phys. Rev., C77 (2008) 064607.
[6] Modified version of the CCFULL code, K. Hagino et al., Computer Phys. Comm. 123 (1999) 143.

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JAEA-Review 2010-056

3.2

Coulomb barrier distribution of quasi-elastic backscattering in 64Ni + 238U
S. Mitsuoka 1 , H. Ikezoe1, K. Nishio1, Y.X. Watanabe 2 , S.C. Jeong2,
Y. Hirayama2, N. Imai2, H. Ishiyama2 and H. Miyatake2

Coulomb barrier distributions have been systematically measured [1,2] and theoretically studied [3,4,5] in
48

Ti, 54Cr, 56Fe, 64Ni, 70Zn, 76Ge and 86Kr + 208Pb reactions relating to Pb-based cold fusion reactions for the

production of super-heavy elements Z=104, 106, 108, 110, 112, 114 and 118, respectively. The barrier
distributions were well reproduced by taking account of the coupling effects of quadrupole vibration for the
projectiles and of the octupole vibration for the 208Pb target [1,3]. Also super-heavy elements up to Z=118
have been produced in hot fusion reactions with actinide targets. Recently, the production of Z=120
element has been tried in 64Ni + 238U reaction. Since 238U nucleus is prolately deformed, the Coulomb
barrier depends on the orientation of the target nucleus. Such orientation effects of the deformed 238U on
fusion and fission processes have been systematically investigated in reactions of 30Si, 36S and 40Al + 238U
[6]. In this experiment we measured the Coulomb barrier distributions and the fission mass distributions in
the 64Ni + 238U reaction as a function of the bombarding energy.
The experiment was carried out by using a large-volume scattering chamber (1.2 m in diameter) newly set
in the JAEA tandem-booster experimental hole. A 238U target prepared by electrodeposition on a Ni foil wasbombarded by 64Ni beams of 310 - 385 MeV with changing the energies in steps of 1.5 MeV. The fission
fragments were detected in coincidence by two position-sensitive multi-wire proportional counters(MWPCs) covering the emission angles of 35° - 85°. The backward scattered particles were detected by 16
solid state detectors (SSDs) arranged annularly with respect to the beam axis at 172° and 164°. Another two
SSDs at 18° monitored the beam. The barrier distributions were obtained by taking the first derivative ofthe quasi-elastic (QE) cross section QE(E) relative to the Rutherford scattering cross section R(E) as afunction of center-of-mass energy E, that is -d{QE(E) /R(E)}/dE. Detailed analysis is in progress for QE
cross sections where deep-inelastic scattering should be carefully excluded by considering the reaction
Q-values of inelastic and transfer channels.
References[1] S. Mitsuoka el al., Phys. Rev. Lett., 99 (2007) 182701.
[2] S.S. Ntshangase et al., Phys. Lett., B651 (2007) 27-32.
[3] Z. Muhammad el al., Phys. Rev., C77 (2008) 034604.
[4] G. Pollarolo, Phys. Rev. Lett., 100 (2008) 252701.
[5] V. I. Zagrebaev, Phys. Rev., C78 (2008) 047602.
[6] K. Nishio el al., Phys. Rev., C77 (2008) 064607.

1
2

Japan Atomic Energy Agency (JAEA)
High Energy Accelerator Research Organization (KEK)- 41 -

JAEA-Review 2010-056

3.3

Measurement of fission fragment mass distribution in the reaction of 40Ar + 238U
K. Nishio 1 , I. Nishinaka1, S. Mitsuoka1, H. Makii1, Y. Wakabayashi1, H. Ikezoe1,
K. Hirose2 and T. Ohtsuki2

In the fusion reactions between 48Ca beams and actinide target nuclei, elements up to 118 have been
produced [1]. The striking feature in the reaction is that the cross-sections do not drop with atomic
number but maintain a few pico-barn values even for the production of the heaviest elements, whichmakes large difference from the cold fusion reactions using lead or bismuth targets [2,3]. A possible
explanation for keeping the larger cross-section would be associated with the static deformation of thetarget nuclei. Because of the prolate deformation of 238U, there is a configuration that projectile
collides on the equatorial side of 238U, which would result in larger fusion probability than thereactions using lead or bismuth target. To investigate the orientation effects on fusion and fission
process, we are measuring the fission fragment properties at the tandem accelerator.
In the reaction of 36S + 238U, we observed strong variation of the fragment mass distribution on thebombarding energy [4]. The data revealed a transition from symmetry to asymmetry mass distribution
when the beam energies were decreased from the above-barrier to sub-barrier values. The symmetricfission results from fusion-fission and the asymmetric fission is associated with quasifission. The
relative yield for quasifission increases when the reaction energy decreases down to the sub-barrierenergy, where projectile collides dominantly on the polar side of 238U. On the other hand, it issuggested that the equatorial collision results in larger fusion-fission probability. In this report, weshow the results of the mass distribution for reactions using heavier projectile 40Ar.
The experiment was carried out by using 40Ar beams extracted from the ECR ion source and accelerated by
the tandem accelerator. The 238U target was made by an electro-deposition method. The fission fragments
were detected in coincidence by position-sensitive multi-wire proportional counters (MWPCs). Fragment
masses are determined by using a conservation law for the mass and momentum. Results for the mass
distributions are shown in Fig. 1. In all the energy range, the distribution has asymmetric shape, whichmeans that quasifission dominates. The asymmetric fission has a peak at around AL / AH = 78 / 200 in Ec.m.
< 187 MeV. In the region of Ec.m. > 187 MeV, an additional asymmetric channel appears at around AL / AH =110 / 168. In spite of the dominant mass asymmetry, the symmetric yields are present. With decreasing
bombarding energy, the yield for symmetric fission decreases. The relative change of thesymmetric/asymmetric fission yields represents the orientation effects.

12Japan Atomic Energy Agency (JAEA)
Tohoku University- 42 -

JAEA-Review 2010-056

Fig. 1Fission fragment mass distributions in the reacition of 40Ar + 238U.

References[1] Yu.Ts. Oganessian, J. Phys., G34 (2007) R165.
[2] S. Hofmann and G. Münzenberg, Rev. Mod. Phys., 72 (2000) 733.
[3] K. Morita et al., J. Phys. Soc. Jpn, 73 (2004) 1738.
[4] K. Nishio et al., Phys. Rev., C77 (2008) 064607.

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JAEA-Review 2010-056

3.4

Fission properties of the neutron-deficient nucleus 180Hg
produced in heavy ion fusion reactions

A.N. Andreyev 1 , R. Chapman1, S. Pain1, I. Tsekhanovich2, M. Venhart3, K. Nishio4, S. Mitsuoka4,
I. Nishinaka4, H. Makii4, Y. Wakabayashi4, H. Ikezoe4, J. Khuyagbaatar5, S. Yan6, K. Hirose7
and T. Ohtsuki7

This research project is motivated by the recent study of the low-energy beta-delayed fission (DF) of180
Tl at ISOLDE (CERN). In the ISOLDE experiment we measured the fission fragment mass
distributions of the weakly-excited nucleus 180Hg populated by the beta decay of 180Tl. An asymmetricmass distribution with the most probable mass split into 80 u and 100 u was observed. This is in astrong contrast to the expected symmetrical mass split in two semi-magic spherical 90Zr nuclei. Also fromthe calculations of the potential energy at scission [2], the symmetric fission with equal mass split was
expected to have the deepest fission valley. However, our calculations based on the five dimensional
deformation space [3], suggests that the observed asymmetric fission originates from the low-lying
asymmetrical saddle point at about E*~10 MeV.
The calculations suggest several fission channels in this nucleus. In order to investigate the presence of the
anticipated fission saddle points and the associated fission channels, we propose to measure the fission
properties from the excited compound nucleus in a broad range in the excitation energies to cover all thepossible saddle point configurations. The most straightforward tool to populate the highly excitedcompound nucleus is to utilize the heavy ion fusion reactions. Therefore, we propose to study fission of180

Hg* produced in several fusion reactions. As a first step, we have carried out the experiment to measure

the fission fragment mass distributions for 36Ar + 144Sm  180Hg* in the excitation energy range between
30 – 65 MeV.
The experiment was carried out at the JAEA tandem accelerator. The 36Ar beams were supplied from the
ECR ion source installed at the terminal section of the tandem accelerator. The beam energies werechanged from 153 MeV to 195 MeV, corresponding to the excitation energy E* =28 – 65 MeV of 180Hg.
The typical beam intensity was 3 paritcle-nA. The 144Sm target of 100μg/cm2 were prepared at the target
laboratory of GSI. Two multi-wire proportional counters (MWPCs) were used to detect the fission
fragments in coincidence. The beam dose was deduced using the number of elastically scattered particles at
an angle of 26.5° relative to the beam axis and with a solid angle of 1.96 msr. The experimental setup was
the same as described in [4]. The data analysis is in progress.
1

University of the West Scotland
The University of Manchester
3
Instituut voor Kern- en Stralighsfysica, KU Leuven
4
Japan Atomic Energy Agency (JAEA)
5
GSI, Germany
6
CIAE, China
7
Tohoku University2- 44 -

JAEA-Review 2010-056

References[1] A. Andreyev et al, ISOLDE proposal IS466, the experiment performed in June 2008.
[2] T. Ichikawa, private communication.
[3] P. Möller et al.,”Nuclear fission modes and fragment mass asymmetries in five-dimention deformation
space”, Nature, 409 (2001) 709 and private communication.
[4] K. Nishio et al., Phys. Rev. C77, 064607 (2008).

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JAEA-Review 2010-056

3.5 Fission fragment anisotropy in heavy-ion-induced fission of actinides
I. Nishinaka 1 , K. Nishio1, M. Tanikawa2, H. Makii1, S. Mitsuoka1,
Y. Wakabayashi1 and A. Yokoyama3

Fission fragment angular distribution in light-ion-induced fission has been explained well by the standard
saddle point model [1]. However, in heavy-ion-induced fission of actinides at near-barrier energies, fission
fragment anisotropy has been found to become anomalously high compared with that expected from thestandard saddle point model [2, 3]. This anomaly of fission fragment anisotropy was thought to originate
from non-equilibrium fission process. The pre-equilibrium K-states model suggests that entrance channelmass asymmetry =(At-Ap)/(At+Ap) plays an important role for fission fragment anisotropy inheavy-ion-induced fission of actinides [4, 5]. At and Ap refer to mass numbers of target and projectile nuclei,
respectively. A limited number of experiments have been carried out to study the effect of different entrance
channels leading to the same compound nucleus, 248Cf (16O+232Th and 12C+236U) [6] and 246Bk (14N+232Th
and 11B+235U) [7]. In order to study the effect of fission fragment anisotropy on entrance channels, wemeasured fission fragment angular distributions in the reactions of 22Ne+232Th ( =0.827) and 12C+242Pu (=0.906), populating the same compound nucleus 254Fm.
A 232Th target was irradiated with 22Ne ions of energy Elab = 120, 116, 112, and 108 MeV at the JAEA
tandem accelerator, excitation energies of the compound nucleus being 56.1, 52.5 48.8, and 45.2 MeV,
respectively. The 232Th target with thickness of 68 g/cm2 was prepared by molecular electrodeposition
onto 89 g/cm2 nickel foil. Fission fragments were measured by four position-sensitive parallel-plateavalanche counters (PPACs) and a silicon surface barrier detector (SSD) as schematically shown in Fig.1.
Each PPAC has the sensitive area of 20×8 cm2 for horizontal (X) and vertical (Y) directions in the reaction
plane. The PPACs have horizontal angles of

= 25º-67º, 73º-105º, 205º-247º, and 253º
-285º in laboratory system. The SSD locatedat = 176º has a solid angle of 0.8 msr. The
experiment for 12C+242Pu was carried out
with the same experimental setup at beamenergies of Elab = 86.4, 82.6, 78.7, and 74.9
MeV, using a 242Pu target with thickness of
37 g/cm2. These beam energies correspondto the same excitation energies of thecompound nucleus 254Fm produced by thereaction 22Ne+232Th.
Fig. 1 Experimental setup.
1

Japan Atomic Energy Agency (JAEA)
University of Tokyo
3
Kanazawa University2- 46 -

JAEA-Review 2010-056

Figure 2 shows the center-of-mass angular distribution of fission fragments in the 86.4 MeV 12C+242Pu,
using the fission fragment kinetic energy predicted by the systematics of Viola et al.[8]. The center-of-massangular distribution provides the fission fragment anisotropy defined as A = W(180º)/ W(90º).

Figure 3

represents preliminary results of the fission fragment anisotropy as a function of the excitation energy of
the compound nucleus by solid circles for 12C+242Pu and open ones for 22Ne+232Th. The error bar indicatesthe uncertainty of experimental angular distribution as shown by dashed lines in Fig. 2. The anisotropy for22

Ne+232Th with smaller entrance channel mass asymmetry = 0.827 shows large values compare withthose for 12C+242Pu with  = 0.906. This implies that entrance channel mass asymmetry plays a role forfission fragment anisotropy in the present fissioning systems.

Fig. 2 The center-of-mass angular
distributions of fission fragments in the 86.4
MeV 12C+242Pu reaction.

Fig. 3 Preliminary results of the fission
fragment anisotropy for 12C+242Pu (solid
circles) and 22Ne+232Th (open circles) as afunction of the excitation energy of thecompound nucleus 254Fm.

References[1] R. Vandenbosch and J. R. Huizenga, Nuclear Fission (Academic, New York, 1973).
[2] S. Kailas, J. Phys., G23 (1997) 1227-1233.
[3] J. P. Lestone et al., J. Phys., G23 (1997) 1349-1357.
[4] V. S. Ramamurthy et al., Phys. Rev. Lett., 65 (1990) 25-28.
[5] Z. Liu et al., Phys. Lett., B353 (1995) 173-178.
[6] R. Vandenbosh et al., Phys. Rev., C54 (1996) R977-R980.
[7] B. R. Behera et al., Phys. Rev., C69 (2004) 064603-1-10.
[8] V. E. Viola. et al., Nucl. Data Tables, A1 (1966) 391.

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JAEA-Review 2010-056

Search for the new isotope 220Pu produced in the fusion reaction 82Kr + 140Ce

3.6

K. Nishio 1 , Y. Wakabayashi1, S. Mitsuoka1, I. Nishinaka1, H. Makii1, H. Ikezoe1, M. Matsuda1,
K. Hirose2, T. Ohtsuki2, S. Yan3, J. Khuyagbaatar4 and H. Miyatake5

Because of the increased binding energy due to the neutron shell at N=126, neutron deficient actinide
isotopes up to element around 100 (Fm) [1] are expected to exist with a life-time detectable in a current
experimental technique, and the nuclei in the vicinity of N = 126 form a ‘peninsula’ in the chart of nuclei.
Search for such nuclei is important to know if the N=126 shell exists or survives in the extreme of neutron
deficient region. As a first step to investigate this region, we are attempting to produce 220Pu (N=126) in thefusion-evaporation reaction 82Kr + 140Ce → 220Pu (2n). The beam energy was chosen so that thecenter-of-mass energy at the middle of the natCe-target layer is 228 MeV, at which the maximum
cross-section for 220Pu is expected. Based on the extrapolation of the fusion probability determined in thereactions of 82Se + 140Ce [2] and 86Kr + 134,138Ba [3] and the statistical model code HIVAP, we calculated
the cross-section to be 5 – 60 pb. The 220Pu is expected to decay by emitting alpha particle, and half-life ispredicted to be 0.3 – 50 ms [1,2]. The decay chain is linked to the known isotopes 212Th (Eα=7.80MeV,
T1/2=30ms) and 208Ra(7.13MeV, 1.3s) via the new isotope 216U, thus we can make unambiguous
identification of the production of 220Pu by observing a few decay chains.
The experiment was carried out by using the JAEA-tandem and booster accelerator. The 82Kr beams (12+)
are extracted by the ECR ion source placed at the terminal section of the tandem accelerator. Typical beam
current on the target position was about 160 pnA. The rotating target was made by sputtering the natCe
metallic material on an aluminum foil with thickness 1.0 μm. The thickness of the natCe layer is about 450
μg/cm2. After the sputtering, we have coated the surface of the Ce-metalic layer by carbon of about 10μmg/cm2 to prevent the oxidation of the material and the loss of material due to the irradiation by the intense
heavy-ion beams. We also prevent the scattering of the beam at the edge of the rotating target wheel byusing the beam chopper system. For this, the rotation angle of the wheel and thus the edge position wasmonitored by using a photo-sensor, whose signal was used to feed a high voltage to operate an electrostatic
deflector to kick and stop the beam. The evaporation residues (ERs) were separated in flight from theprimary beams and other reaction products by using the JAEA recoil mass separator and transported to a
focal plane. At the focal plane, a silicon strip detector was mounted to detect the implanted recoils andsubsequent alpha-decay chains. To measure a time-of-flight (TOF) of the implanted recoils, we mounted
two timing detectors in front of the focal plane detectors. The TOF signal and implanted energy signal wasused to make a rough estimate for the mass of ER, which can be well separated from the backgroundparticles.
1

Japan Atomic Energy Agency (JAEA)
Tohoku University
3
China Institute of Atomic Energy (CIAE)
4
GSI, Germany
5
KEK
2- 48 -

JAEA-Review 2010-056

We accumulated a beam dose corresponding the production cross-section 10 pb. We are making a data
analysis to search for the candidate of the production of 220Pu.
References[1] H. Koura, private communication.
[2] P. Moller, At. Data and Nucl. Data Table, 66 (1997) 131-343.
[3] K. Nishio et al., Phys. Rev., C63 (2001) 044610.
[4] K.Satou et al., Phys.Rev., C73 (2006) 03460.
[5] W. Reisdorf and M. Schaedel, Z. Phys., A343(1992) 47.

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JAEA-Review 2010-056

3.7Study of 218U region near N=126 closed shell

Y. Wakabayashi 1 , K. Nishio1, S. Mitsuoka1, I. Nishinaka1, H. Makii1, R. Takahashi1,
S. Yan1, H. Miyatake2 and S. Ota3

Synthesis of new actinide nuclei near the N=126 closed shell is interesting to know the stability of the
N=126 closed shell [1]. In order to study this stability, we have carried out the experiment to produce a newisotope 216U in the fusion reaction of 82Kr+138Ba and to measure its alpha-decay energies and half-life.
The experiment to produce 216U was performed using the 138Ba (82Kr, 4n) 216U reaction. The calculated
cross section of 216U is estimated about 100 pb using the HIVAP code [2]. The 82Kr12+ beam of 393 MeV
was supplied from JAEA-tandem accelerator and used to bombard the rotating 138Ba target foil. The 138Ba
target of 350 g/cm2 thickness was made by sputtering a 99%-enriched material of 138Ba isotope on a 0.8mm aluminum foil. A total dose of 3.6x1015 was irradiated on the target for two days. Evaporation residues(ER’s) emitted to the beam direction were separated from the 82Kr beam by a recoil mass separator(JAEA-RMS). The separated recoils were implanted into a double-sided position-sensitive strip detector(PSD; 73x55 mm2). Two Multi Channel Plates (MCP’s) were used for timing detectors to obtain thetime-of-flight (TOF) signal of the ER’s. One was placed in front of the PSD and the other 30 cm upstream
the PSD, The presence of the signal in the timing detectors was also used to separate the decay in the
PSD from the recoil implantation.
Figure 1 and 2 show two dimensional
spectrum of the recoil energy versus TOF
obtained from the calibration run of the82

Kr+130Te reaction and the run of the82

Kr+138Ba reaction, respectively. In Fig. 1, it

was found that the ER’s were discriminatedfrom the background particles. Energy
calibration of the PSD was performed using
known  lines from

204

209

207

Fr(6.65 MeV), and82

130

produced in the Kr+
Fig. 1 Two dimensional spectrum of the energy versus
TOF obtained from the 82Kr+130Te reaction. The unitof X and Y axis are MeV and ch, respectively. The
region of dashed line is the part of ER’s.
1

Japan Atomic Energy Agency (JAEA)
High Energy Accelerator Research Organization (KEK)3
Center for Nuclear Study, University of Tokyo (CNS)2- 50 -

Rn(6.42 MeV),
Ra(7.13 MeV)

Te reaction. In Fig. 2,

the region of dashed line shows the expectedarea of ER’s produced by the 82Kr+138Ba
reaction.

We

obtainedcross-section of 50 pb foran216

upper-limit

U. Data analysis

JAEA-Review 2010-056

is now in progress.

Fig. 2 Two dimensional spectrum of theenergy versus TOF obtained from the82
Kr+138Ba reaction. The unit of X and Y
axis are MeV and ch, respectively. The
dashed line shows the expected area of
ER’s.

References[1] H. Koura and T. Tachibana, BUTSURI, 60 (2005) 717-724 (in Japanese).
[2] W. Reisdorf and M. Schadel, Z. Phys., A343 (1992) 47-57.

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JAEA-Review 2010-056

3.8

Production of 256Lr with the 249,250,251Cf(11B, xn) and 243Am(18O, 5n) reactions
N. Sato 1 , M. Asai1, K. Tsukada1, T.K. Sato1, A. Toyoshima1,
Z.J. Li1, T. Kikuchi1, S. Ichikawa2 and Y. Nagame1

It is quite important to determine first ionization potentials (IPs) of superheavy elements (SHEs) tounderstand their electronic structure affected by increasingly strong relativistic effects. The IP of the lastactinide, lawrencium, is predicted to be lower than those of other actinides. We are planning to measure theIP of Lr using a surface ionizer coupled with an isotope separator on-line at JAEA (JAEA-ISOL) with 256Lr
which has a relatively longer half-life of 27 ± 3 s and higher -decay branching ratio of 85 ± 10% [1]. In
the present study, to determine the optimum reaction and bombarding energy for the production of 256Lr, wemeasured the excitation functions of the 249,250,251Cf(11B, xn) and 243Am(18O, 5n) reactions.
A 249,250,251Cf target (249Cf: 62%, 250Cf: 14%, and 251Cf: 24%) with 0.185 mg/cm2 thickness and an 243Am
target with 0.36 mg/cm2 were irradiated with 11B4+ and 18O6+ beams, respectively. The beam energies were57, 60, 63, 66, 69, and 72 MeV for 11B and 93, 96, and 99 MeV for 18O in the middle of the target. Nuclear
reaction products recoiling out of the target were transported with a He/KCl gas-jet system through a 25-mlong Teflon capillary to the rotating wheel -particle detection system (MANON) at a He flow rate of 2.4
L/min. The gas-jet transport efficiency was estimated to be 30%. The transported products were deposited
on a PET foil with 0.12 mg/cm2 thickness and 20 mm diameter, eighty of which were arranged at the
periphery of a wheel of MANON. After collection for 10 s, the wheel was stepped at 10-s intervals to
successively place the deposited sample in front of 18 Si PIN photodiodes (Hamamatsu S3204). Eachdetector had 30% detection efficiency. Energy resolution of the detectors was 20 keV FWHM in average.
Energy calibration was performed with a standard 241Am source and detecting -particles from known
nuclei produced in the target chamber and transported to the MANON system.
Figure 1 shows a typical -particle spectrum measured in 10-180 s after collection in the bombardment of
the 249,250,251Cf target with the 63 MeV 11B beam. Alpha-lines from 256Lr are clearly observed at 8320, 8390,
8430, 8480, 8520, and 8620 keV. As discussed in Ref. [2], the 8430 keV peak would contain -particles
from 256No fed by the EC decay of 256Lr. The decay curve for 8480, 8520, and 8620 keV -groups of 256Lr
is shown in Fig. 2. The half-life corresponding to these -lines were determined to be 25 ± 2 s as shown in
Fig.2, which is in agreement with the literature value [1]. Excitation functions of the 249,250,251Cf(11B,xn)256Lr and 243Am(18O, 5n)256Lr reactions are shown in Figs. 3(a) and (b), respectively. For the249,250,251

Cf(11B, xn)256Lr reactions, the maximum cross section of 200 ± 15 nb is found at the 11B beamenergy of 63 MeV. The present cross-section is smaller than the literature value of approximately 300 nb
for the 249Cf(11B, 4n)256Lr reaction at the same energy [2]. On the other hand, the maximum cross section of
the 243Am(18O, 5n)256Lr reaction is 39 ± 4 nb at 96 MeV, which is slightly larger than the reported value of1
2

Japan Atomic Energy Agency (JAEA)
RIKEN- 52 -

JAEA-Review 2010-056~30 nb [3]. It seems that the previous cross section value was underestimated because -particle energy of256
18

Lr was not completely identified at that time. The 249,250,251Cf + 11B reaction is preferable to the 243Am +O reaction for the 256Lr production. In the future, the first IP of Lr will be measured using a gas-jet

transport system coupled with a surface ionizer in JAEA-ISOL.
257

256

No

Lr

255

Lr (8380)
8390

8430

T1/2 = 25 ± 2 s

256

No (8400, 8450)

8480
8520
8320
8620

.

Fig. 1 Alpha-particle spectrum measured in thebombardment of the 249,250,251Cf target with
63-MeV 11B ions.

Fig. 2 Decay curve of 256Lr from the sum of
-groups of 8480, 8520 and 8620 keV. The solidline shows the result of the exponential fit.

(a) 249,250,251Cf(11B, xn)256Lr(b) 243Am(18O, 5n)256Lr

Fig. 3 Excitation functions of the reactions of (a) 249,250,251Cf(11B, xn)256Lr and (b) 243Am(18O, 5n)256Lr.
The broken lines represent results with a HIVAP code calculation, where the isotopic composition of
the Cf target used was taken into consideration.

References[1] Y.A. Akovali, Nucl. Data Sheets, 87 (1999) 249-316.
[2] K. Eskola et al., Phys. Rev., C 4 (1971) 632-642.
[3] G.N. Frelov et al., Nucl. Phys., A 106 (1968) 476-480.

- 53 -

JAEA-Review 2010-056

3.9

Measurement of fission probability of 240Pu produced by nucleon transfer reaction
238
U(18O, 16O)240U
K. Nishio 1 , I. Nishinaka1, S. Mitsuoka1, H. Makii1, R. Takahashi1, Y. Wakabayashi1, K. Furutaka1,
K. Hirose2, T. Ohtsuki2, S. Yan3 and S. Chiba1

Neutron-induced fission cross-section and neutron multiplicity per fission are important for the design of
nuclear reactors. The next generation nuclear reactor is designed to have the relatively high energy neutrons
to make an efficient production of the burnable isotopes and to transmute the long-lived minor actinides. To
simulate such reactors, nuclear data for minor actinides with short half-life are also needed. However, few
experiments were performed on such nuclei because of the difficulty to prepare such a target materials.
Some of the data is practically impossible to obtain using a neutron source. To obtain these data, so called‘surrogate reactions’ are proposed [1]. In this approach, a compound nucleus same as the one produced byneutron capture is populated by heavy-ion induced nucleon transfer reactions and the decay probability tofission is determined. The cross-section to form the compound nucleus is calculated in a model calculation,
which is multiplied to the fission decay probability to determine the neutron-induced fission cross-section.
We propose to investigate the reaction 238U(18O, 16O)240U for the surrogate of 239U(n,f) (the half-life of 239U
is 23 min), and the test experiment was carried out to check the feasibility of the fission cross-section
measurement. The fission probability is determined from the number of coincidence between 16O andfission fragments divided by singles events for 16O. In this experiment, a test experiment to see thecoincidence rates between 16O and fission fragments was carried out.

The experiment was carried out using the 144-MeV 18O beams from the tandem accelerator. The
238

U target (82μg/cm2 ) was made by electrically depositing the natural uranium on a nickel backing.

The 16O produced by nucleon transfer were separated by using a ⊿E – E silicon detector [2]. The
detector covered the angle from 32 o to 49o relative to the beam direction. The thickness of the ⊿E
detector was chosen to be 75 μm.

An annular type Si-strip detector was used for the measurementof the residual energy. Energy resolution to determine the excitation energy for 240U was 1.3 MeV(FWHM). Fission fragments following the nucleon transfer were detected in coincidence by using a
position-sensitive multi-wire proportional counters (MWPCs) [3].
Figure 1 shows the number of fission events coincided with 16O, plotted as a function of theexcitation energy of 240U. The equivalent neutron energy which gives the same energy scale in thereaction 239U(n,f) is also shown. The coincidence events sharply increases at E* = 5.5 MeV, fromwhich fission barrier height of 240U is determined to be 5.5±0.6 MeV. This value is close to 5.7 MeV(inner barrier) determined from the (t,p) reaction [4] .

1

Japan Atomic Energy Agency (JAEA)
Tohoku University
3
China Institute of Atomic Energy (CIAE)
2- 54 -

JAEA-Review 2010-056

Fig. 1

Numer of fission events coincided with 16O plotted as a function of the excitation energy of 240U.

References[1] S. Chiba et al., Phys. Rev., C81 (2010) 044604.
[2] T. Ishii et al., Phys. Rev., C78 (2008) 054309(1-11).
[3] K. Nishio et al., Phys. Rev., C77 (2008) 064607.
[4] S. Bjornholm and J.E.Lynn, Rev. Mod. Phys., 52 (1980) 725.

- 55 -

JAEA-Review 2010-056

3.10 Development of a measurement system for (n,) cross sections
using the surrogate reaction methods
H. Makii 1 , T. Ishii1, D. Nagae2, R. Takahashi3, S. Mitsuoka1, S. Chiba1,
H. Miyatake4, S.C. Jeong4, N. Imai4 and Y. Hirayama4

Neutron-capture reaction with unstable nuclei plays an important role in the stellar nucleosynthesis. In the
nucleosynthesis by slow neutron-capture process (s-process) half lives of some unstable nuclei are long
lived that the (n,) reactions can compete with  decay. Such long-lived nuclei act as branching points in
the reaction path of the s process. In order to understand the stellar conditions for the s-process
nucleosynthesis, (n,) reaction rates of unstable nuclei over a wide stellar temperature range from kT ~ 8
keV to kT ~ 90 keV are required [1]. In addition, (n,) cross sections of long-lived fission products (LLFPs)
are the most important physical quantities for the study on transmutation of nuclear wastes. Improvementsin small errors of the cross section within the thermal and epithermal neutron energies below about 1 MeV
are needed to develop the technology to efficiently transmute LLFPs using reactors (fast or thermal) or
accelerator driven system. The measurement of the (n,) cross section of the unstable nuclei in the keV
region are very difficult. The main reasons of the difficulty are due to a sample preparation and/or
radioactivity of the sample. Recently, (3He,p ), (d,p ), (3He, 3He’ ), and (3He, 4He ) reactions have been
proposed as surrogate reactions for (n,) reactions [2-4] on the basis of the assumption that the formationand decay of a composite nucleus are independent of each other (for each spin J and parity ). At thepresent time, however, the feasibility of the theses reactions have not been demonstrated; e.g., J 
distributions of composite nuclei and reaction mechanisms such as multi-nucleon transfer reactions are notassessed.
Hence, we designed a new experiment in order to measure the  rays from the highly excited states
produced by surrogate reactions in coincidence with outgoing particles. In this experiment, we will use ahigh-efficiency anti-Compton NaI(Tl) spectrometer with a large S/N ratio to detect the  rays and Si E-E
detector with high resolution to detect the outgoing particles. The anti-Compton NaI(Tl) spectrometerconsists of central NaI(Tl) detector with a diameter of 228.6 mm and a length of 203.2 mm, and an annular
NaI(Tl) detector with a thickness of 50.8 mm and a length of 368.3 mm [5]. This spectrometer was used forthe measurement of keV neutron capture cross section of a stable nucleus from an astrophysical interest[6,7]. The Si E-E detector consists of two surface-barrier type Si detectors with a thickness of 80 m (E
detector) and 4mm (E detector), and has an annular active-area covering an angle range of 123o – 152o withrespect to the beam axis.
First on-line test of the measurement system was carried out using 24 MeV 3He beam of 1.0 particle nA .
1

Japan Atomic Energy Agency (JAEA)
University of Tsukuba
3
Tokyo University of Science
4High Energy Accelerator Research Organization (KEK)2- 56 -

JAEA-Review 2010-056
The target consisted of 266 g/cm2 196Pt (94.6% enrichment) deposited on 1.07 m aluminum foil. Fig. 1
shows the time difference (t) between signals from the Si E-E detector and the NaI(Tl) spectrometer.
Observed events are given as a function of the time relative to the time (t = 0 ns) for the events at the 196Pt
target. In Fig. 1 we see clearly the peak at t = 0 ns which indicate that the -ray events were observed incoincidence with outgoing particles. From the result of the present on-line test, our new measurement
system seems to have enough sensitivity to measure the  rays from the 3He induced reactions incoincidence with outgoing particles.

Counts / 0.24 ns(X 104)
1.5

1

10 ns
(FWHM)

0.5

0

-400

-200

0

t (ns)200

400

Fig. 1 Time difference (t) between signals from the Si E-E detector and the NaI(Tl) spectrometer. Here,the detected events are shown as a function of the time relative to the time (t = 0 ns) for the events at thetarget position.

References[1] F. Kappeler and A. Mengoni, Nucl. Phys., A777 (2006) 291-310.
[2] S. Boyer et al., Nucl. Phys., A775 (2006) 175-187.
[3] B.L. Goldblum et al., Phys. Rev., C78 (2008) 064606.
[4] J.M. Allmond et al., Phys. Rev., C79 (2009) 054610.
[5] T. Ohsaki et al., Nucl. Instrum. Methods Phys. Res., A425 (1999) 302-319.
[6] Y. Nagai et al., Astrophys. J., 372 (1991) 683-687.
[7] M. Igashira et al., Astrophys. J., 442 (1995) L89-L92.

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JAEA-Review 2010-056

3.11High energy alpha particles emitted from nuclear reaction

N. Imai 1 , H. Ishiyama1, Y. Hirayama1, S.C. Jeong1, H. Miyatake1, Y.X. Watanabe1,
H. Makii2, S. Mitsuoka2 and K. Nishio2

When we performed the test experiment of proton resonance elastic scattering in inverse kinematics with68

Zn beams and a polyethylene target, we observed much more heavier ions than atomic number Z = 1 asalready reported elsewhere in this report.. The origin of the particles seems not to be explained by any
reaction mechanisms. To discuss the reaction mechanism, we need experimental information of energies
and angular distributions, as well as the particle identification. Since the gain of the detector used was
optimized to the several MeV energy loss in order to measure the energy of protons precisely, however, wewere not able to identify the heavy ions. Thus, we performed another experiment with lower gain and tried
to identify the ions.
The experiment was performed at JAEA tandem accelerator facility. A 68Zn beam of 5.5 MeV/nucleon was
accelerated by tandem accelerator and superconducting booster linac. The beam of around several enA was
focused on a 10 mg/cm2 thick carbon. We put a 1.0 mm thick aluminum plate as an energy degrader justdownstream of the target. The energy of recoil particles were measured by the three layers of silicon
semiconductors (SSDs) of 50 x 50 mm2 which were mounted 50 cm downstream of the target. The
thickness of each SSD was 300 m. As the first layer SSD, a position sensitive detector was used to obtain
the hit position.
Figure 1 shows the energy correlation between the energy deposit in first layer SSD and the sum of energy
losses in all SSDs. The alpha and protons were clearly separated. In addition to these particles, a large
amount of ions which stopped in the first layer were detected, indicating that the charged particles whose
atomic numbers were greater than Z=2 were also produced.
Even with the 1 mm thick aluminum energy degrader, some of alpha particles punched through the three
SSDs. The smallest energy loss in the first layer of alpha was about 7.5 MeV. Assuming that the alphaparticles were produced at the upstream surface of the target, the energy loss would be generated by alphaparticles of 23 MeV/nucleon by taking into account the energy losses at the energy degrader and the target.
When we selected the alpha particles punched through the SSDs, the hit positions at the SSDs were limited
to be within 1 cm  in 1 , giving rise to the scattering angles of as small as 1 degree.
The mechanisms to produce such a high-energy alpha particle may be a fusion-evaporation reaction, and/ora transfer reaction. When we calculate the energies and angular distributions of alpha particles using afusion-evaporation code PACE4 [1], the alpha will be emitted at the angles larger than 10 degrees, showing

1
2

High Energy Accelerator Research Organization (KEK)
Japan Atomic Energy Agency (JAEA)- 58 -

JAEA-Review 2010-056

inconsistency with the experimental data. On the other hand, the energy of alpha particles produced by atransfer reaction of 12C(68Zn, )76Se is calculated to be 33 MeV/nucleon when the 68Zn beam of 5.5
MeV/nucleon reacted with 12C nuclei, which seems consistent with the experimental data. However,according to the kinematics, the energy is as large as 32 MeV/nucleon even at 20 degrees in the laboratory
frame. The theoretical angular distribution of high2010/05/19 18.14

energy alpha particles appeared inconsistent with the

In summary, we successfully identified alpha particles
produced by nuclear reactions of the 68Zn beam withE (MeV)

experimental data.

60
60

50
50

α

40

40

the carbon target. The highest energy of alpha wasestimated to be 23 MeV/nucleon. In addition to alpha,
we observed heavier ions whose atomic numbers were

3030
2020

p

larger than Z=2 nuclei. Two reaction models,fusion-evaporationandtransfer

reactioncannotexplain the experimental data. Further detailed
experiments

areawaitedtounderstand

the

1010
00 0
0

5

5

10

10

15

15

20

20

BLOW PSD1vstotE

phenomenon.

25

25

30

30

35

35

40

ΔE (MeV)40

Fig. 1 Energy correlation between E and E. Protonsand  were clearly distinguished.

References[1] A. Gavron,Phys. Rev., C21 (1980) 230.

- 59 -

JAEA-Review 2010-056

3.12Development of GEM-MSTPC for measurement of the 8Li(, n)11B reaction

H. Ishiyama 1 , K.Yamaguchi 2, Y. Mizoi3, Y.X. Watanabe1, S.K. Das3, M-H. Tanaka1, T. Hashimoto5,
Y. Hirayama1, N. Imai1, H. Miyatake1, T. Nomura1, T. Fukuda3, S. Mitsuoka4, H. Makii4, K. Nishio4,
T.K. Sato4, M. Matsuda4, Y. Wakabayashi4, H. Yamaguchi5, S. Kubono5 and S. Hayakawa5
We have developed an active-target type gas detector, a Gas Electron Multiplier [1] Multiple-Sampling andTracking Proportional Chamber (GEM-MSTPC) operating with low-pressure He-base mixed gas, where
He is used as a target for studies of astrophysical nuclear reactions, especially He capture reactions. The
measurement of the 8Li(, n)11B reaction cross sections is proposed using a high-intense (~105 pps) 8Li
beam from TRIAC (RNB07-K05). For high injection-rate capability, a 400 m thick GEM (THGEM) [2] isadopted to overcome space-charge gain limitation of a wire counter. We examined performance of different
kinds of THGEMs using low-energy heavy ion beam from TRIAC. The GEM-MSTPC consists of a drift
space (active volume of 100 mm3), one or more THGEM and an anode plate which is composed ofbackgammon-type electrodes to measure trajectories of charged particles in the horizontal plane. Typicaloperating gas and its pressure are He + CO2 (10%) and 16 kPa, respectively, for the measurement of the8Li(, n)11B reaction cross sections.

First of all, the gas gain on the THGEM was measured under the required condition of the operating gas.
The measured gas gain was high enough (~103) in the single THGEM configuration [3]. Then, we
measured time dependence of pulse height of anode output by injecting 4He from an 241Am source and/or
low-energy (E = 13.2 MeV) 12C provided by TRIAC. In order to suppress ion feedback [3], the double
GEM configuration was adopted. A pulse-height shift was observed with the previously developed
THGEM [2]. This phenomenon comes from the gas-gain instability due to charge up of the insulator
between the GEM electrodes. It strongly depends on the structure of micro holes punching through theelectrodes [4]. In order to avoid the charge up, we modified the structure and the surface of the electrode.
TABLE 1 shows a summary of the modifications together with observed pulse-height shifts under various
injection rates. THGEM #1 indicates the previous THGEM having an insulator rim of 100 m widtharound the hole. THGEM #2 has no rim and the gain shift was suppressed within 12% under the 104 pps
4He injection rate. However, a discharge often occurred in several hours from the beginning of the 104 pps

injection, and after that the gain became unstable. In order to avoid the discharge, the hole diameter of #3
was changed to be smaller than of #2. Although the gain shift for #3 was suppressed within 5% under the4

He injection rate of 104 pps, it became larger (about 8%) in the case of the 12C injection with the intensityof 105 pps as shown in the left panel of Fig. 1. Moreover, the gain shift for #3 gradually increased in several
measurements for the 104 pps 4He injection. Actually, the shift was about 1% at the 1st measurement,
whereas it changed to be 5% at the 3rd measurement. This phenomenon could be explained as the ‘ageing’1High Energy Accelerator Research Organization (KEK)
University of Tsukuba
3Osaka Electro-Communication University
4
Japan Atomic Energy Agency (JAEA)
5
Center for Nuclear Study (CNS), University of Tokyo2- 60 -

JAEA-Review 2010-056

of the electrodes [5], such like, oxidation of the copper electrode surface. Hence, we coated the electrode of#4 with gold. THGEM #4 showed a good gain stability as shown in the right panel of Fig. 1. The pulse
height became stable within 3% under the 12C injection rate from 400 pps to 120 kpps.
THGEM#
Hole diameter [m]Rim
Hole pitch [m]Electrode surface
4
Pulse
He (E = 5.4 MeV, 100 pps )4heightHe (E = 5.4MeV, 104 pps )12
shift (%)
C (E = 13.2 MeV, 105pps)

100k pps

#1
300
yes
700
Au
100
n/a
n/a

#2
500
no
700
Cu
a few
12
n/a

#3
300
no
700
Cu
n/a
1~5
8

#4
300
no
700
Au
n/a
n/a
<3

120k pps

500 pps

Table 1. Summary ofmodified THGEMs. The
hole structure of THGEM
was changed for #1, #2,#3. The surface of thecopper electrode wascoated by gold for #4.
“n/a”
indicatesnomeasured value.

400 pps

Fig. 1 Pulse-height shifts under the 12C beam injection rate from 400 pps to 105 pps using THGEM #3 (leftpanel) and THGEM #4 (right panel). The horizontal axis indicates time from the beginning of the beam
injection.

The energy resolution under the 12C injection rate of 105 pps was also measured. It was obtained from the
distribution of energy-loss signals for each segmented anode pad. The energy resolutions under the
injection rate of 400 pps for #3 and for #4 were both 7% in . That under the injection rate of 105 pps for#3 was 13%, while for #4 it was improved to be 8%.
The characters of the gain stability and the energy resolution under the high injection rate for #4 satisfy
experimental requirements. The GEM-MSTPC using THGEM #4 (400 m thick, 300 m hole diameter, Cu
electrode coated by Au, no rim) was successfully applied to the measurement of the 8Li(, n)11B reaction
cross sections on April 2010.
References[1] F. Sauli, Nucl. Instrum. Methods Phys. Res., A386 (1997) 531-534.
[2] C. Shalem, et al., Nucl. Instrum. Methods Phys. Res., A558 (2006) 475-489.
[3] K. Yamaguchi, et al., Nucl. Instrum. Methods Phys. Res., A (2010), doi:10.1016/j.nima.2010.02.173.
[4] J. Benlloch, et al., Nucl. Instrum. Methods Phys. Res., A419 (1998) 410-417.
[5] F. Sauli, Nucl. Instrum. Methods Phys. Res., A515 (2003) 358-363.

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JAEA-Review 2010-056

CHAPTER 4
Nuclear Chemistry

4.1

Cation-exchange behavior of rutherfordium, 104Rf
in H2SO4/HNO3 mixed solution ([H+] = 1.0 M)

4.2

Reduction of mendelevium using an electrochemistry apparatus

4.3

On-line isothermal gas chromatographic behavior of group-5 elements
as homologues of Db

4.4

Gas-phase chemistry of Zr and Hf using carbon cluster transport system- 63 -

This is a blank page.

JAEA-Review 2010-056

4.1

Cation-exchange behavior of rutherfordium, 104Rf in H2SO4/HNO3 mixed solution([H+] = 1.0 M)
Z.J. Li 1 , A. Toyoshima1, M. Asai1, K. Tsukada1, T.K. Sato1, N. Sato1, T. Kikuchi1, X.H. Liang2,
Y. Kasamatsu3,4, Y. Nagame1, S. Goto5, H. Haba3, Y. Takeda6, S. Ikarashi7, M. Murakami5,
M. Nishikawa6, Y. Komori4, K. Ooe4, K. Akiyama8 and K. Sueki7

Transactinide elements with atomic numbers Z ≥ 104 are produced in heavy-ion-induced nuclear reactionsat accelerators with extremely low production rates and are only available as short-lived isotopes. Any
chemistry study must be carried out on an “atom-at-a-time” scale, completed within their life time, andrepeated thousands of times to gain satisfied statistics. Such studies offer unique opportunities to obtain
information on trends in the Periodic Table and to probe magnitude of the influence of relativistic effects[1]. So far, we have investigated complex formation of Rf using an automated ion-exchange separation
apparatus coupled with the detection system for alpha-spectroscopy (AIDA): chloride, nitrate, and fluoride
complexes [2]. In the present work, cation-exchange behavior of Rf in H2SO4/HNO3 mixed solution ([H+] =1.0 M) has been studied using AIDA to clarify properties of Rf sulfate complexes by comparing them withthose of the lighter homologues Zr and Hf complexes.
The isotope 261Rf (T1/2 = 78 s) was produced with a Cm/Gd mixed target using 94 MeV 18O6+ beam from the
JAEA tandem accelerator. 3.24 min-169Hf was produced simultaneously in the Gd(18O, xn) reaction tomonitor behavior and chemical yields of Hf. Reaction products were transported to a chemistry lab by a
He/KCl gas-jet and were deposited on a collection site of AIDA for 2 min. After deposition, the products
were dissolved with 280 μL H2SO4/HNO3 ([H+] = 1.0 M) of various H2SO4 concentrations of 0.15, 0.25,
0.30, 0.35, 0.40, 0.50, and 0.69 M, and were fed onto a 1.6 mm i.d. × 7.0 mm cation-exchange column(CK08Y) at a flow rate of 670 μL/min. The effluent was collected on a Ta disk as fraction 1. The remaining
261

Rf and 169Hf were stripped with 250 μL 0.1 M HF/0.1 M HNO3 at a flow rate of 1000 μL/min and werecollected on another Ta disk as fraction 2. Two fractions were evaporated to dryness and were automaticallytransferred to α-spectrometry stations of AIDA equipped with eight 600 mm2 passivated ion-implanted
planar silicon (PIPS) detectors. From the radioactivities A1 and A2 observed in fractions 1 and 2,
respectively, adsorption probability (%ads) was evaluated using the equation of %ads = 100A2/(A1+A2).
After the α-particle measurement, the 493 keV γ-ray of 169Hf was measured with Ge detectors. The
chemical yields of Hf were approximately 60%. To investigate behavior of Zr and Hf simultaneously, 7.86
min-85Zr and 169Hf were produced with a Ge/Gd mixed target in the Ge(18O, xn) and Gd(18O, xn) reactions,
1

Japan Atomic Energy Agency (JAEA)
China Institute of Atomic Energy (CIAE)
3
RIKEN
4
Osaka University
5
Niigata University
6
Kanazawa University
7
University of Tsukuba
8
Tokyo Metropolitan University2- 65 -

JAEA-Review 2010-056

respectively.
From the 2318 cycles of the 261Rf experiments, a total of 185 α-events from 261Rf (8.28 MeV) and its
daughter 25 s-257No (8.22, 8.32 MeV) were registered in the energy range of 8.0−8.4 MeV, including 23
time-correlated α-α pairs of 261Rf and 257No. An accumulated α-spectrum obtained in the 0.15 M
H2SO4/HNO3 experiment is shown in Fig. 1. The contribution of 257No formed during the collection andseparation to 261Rf was evaluated to be 1.1−28% based on separate cation-exchange studies of 3.1
min-255No, produced in the 248Cm(12C, 5n) reaction, under the identical conditions to the Rf experiments.
The contribution of background and the growth and decay of 261Rf and 257No were also taken into accountto evaluate the adsorption probability of 261Rf.
Figure 2 shows variations of the adsorption probabilities of Rf, Zr, and Hf as a function of [HSO4-]. The
adsorption probabilities of Hf measured in the separate two experiments agree well with each other. The
adsorption probabilities of Rf, Zr, and Hf on the CK08Y resin decrease with an increase of [HSO4-],
indicating successive formation of sulfate complexes of these elements. It is found that the %ads values of
Rf decrease at much higher [HSO4-], indicating that the sulfate complex formation of Rf is much weaker
than that of Zr and Hf. This trend is similar to that of the fluoride complex formation of the group-4
elements. In the previous study, the fluoride complex formation of Rf was found to be remarkably weaker
than that of Zr and Hf. From the HSAB (hard-soft-acid-base concept) point of view, the sulfate ion SO42- isa hard anion like F-, and interacts stronger with smaller (harder) cations. The ionic radius of Rf4+ is
expected to be much larger than those of Zr4+ and Hf4+ [3], resulting in a weaker sulfate complex formationof Rf4+ as compared to Zr4+ and Hf4+, which qualitatively explains the present complexation trend.

Adsorption probability / %Rn)

No 8.22, 8.32

Rf 8.28

257

214

261

Po 7.687 (Daughter of

Fr 6.534
211

Fr 6.543,

210

5
0
5

222

Rn)

222
218

10

Po 6.003 (Daughter of

15

244

Counts / 10 keV

20

Cm 5.763, 5.805

25
100

85

80

Zr (Ge/Gd)169

Hf (Ge/Gd)261

Rf (Cm/Gd)

169

Hf (Cm/Gd)

60
40
20
0

5.5

6

6.5

7

7.5

8

8.5

0

9

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8-[ HSO ] / M

Energy / MeV

4

Fig. 1 α-spectrum accumulated from the 283 cycles of
the Rf experiments with 0.15 M H2SO4/HNO3.

Fig. 2 variations of adsorption probabilities of Rf,
Zr, and Hf on CK08Y as a function of [HSO4-].

References[1] M. Schädel, Angew. Chem. Int. Ed., 45 (2006) 368-401.
[2] Y. Nagame, J. Nucl. Radiochem. Sci., 6 (2005) A21-28.
[3] V.G. Pershina, Chem. Rev., 96 (1996) 1977-2010.

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JAEA-Review 2010-056

4.2

Reduction of mendelevium using an electrochemistry apparatus

A. Toyoshima 1 , K. Tsukada1, M. Asai1, T.K. Sato1, Z.J. Li1, N. Sato1, T. Kikuchi1, Y. Kitatsuji1,
Y. Nagame1, K. Ooe2, Y. Kasamatsu2, A. Shinohara2, H. Haba3 and J. Even4

It is important to determine redox potentials of the heaviest actinides between divalent and trivalent states.
Due to the drastic stabilization of the 5f orbital with increasing atomic number, divalent states are predicted
to be stabilized at the end of the actinide series. Though pioneering chemical works demonstrated thestabilized divalent state at No, redox potentials of other heaviest actinides have not been precisely
determined because of single atom chemistry. Purpose of our present study is the precise determination of aredox potential between Md2+ and Md3+ using our electrochemistry apparatus [1]. In this study, we firstmeasured the excitation function of the 248Cm(11B, 4n)255Md reaction to find an optimum production
condition. Then the reduction of Md3+ to Md2+ was examined using the apparatus.
The 525 g/cm2-thick 248Cm target was prepared by electrodeposition of a Cm compound in 2-propyl
alcohol onto a 1.80 mg/cm2 Be backing foil. The 11B4+ ions of 58.2, 59.7, 61.2, 63.2, and 65.2 MeV passed
through a 1.99 mg/cm2 HAVAR window, 0.09 mg/cm2 helium cooling gas, and the Be backing foil before
entering the 248Cm target material. An effective thickness of the Cm target for the production of 255Md ions
was evaluated to be ~250 g/cm2. The beam energy in the middle of the target was 52.5, 54.1, 55.8, 57.8,
and 60.0 MeV, respectively. An average beam intensity was 945 particle nA. Reaction products recoilingout of the target were transported by a He/KCl gas-jet method to the chemistry laboratory through a Teflon
capillary at a helium flow rate of 2.4 L/min. For 2 min, the transported products were deposited on a thinpolyethylene telephtalate (PET) film, eighty of which were arrayed along a periphery of a wheel of therotating wheel measurement system (MANON). After collection, the deposited sample was successively
moved to stations by the stepwise rotation of the wheel at 2-min intervals. At the first 18 stations,-particles of the samples were measured with 18 Si detectors placed at a distance of 5 mm.
In the reduction experiment of Md, the transported products by the He/KCl gas-jet method were deposited
on a collection site of a chemistry apparatus for 10 min. After collection, the deposited products weredissolved with 0.1 M HCl and were subsequently fed into an HDEHP column to remove KCl from thecollected sample because KCl in measured samples lowers -energy resolution with a Si detector. The 0.1
M HCl effluent containing K+ ions was discarded. After 9 cycles of the above procedures, the remaining
products on the column were stripped with 6.0 M HCl. The effluent was collected on a Ta disk and wasevaporated to dryness with a halogen lamp and a helium gas stream. After dissolution of the dried sample
with 0.1 M HCl, the aliquot was injected into the electrochemistry apparatus with 0.1 M HCl which was
beforehand electrolyzed using another electrolytic column apparatus to decrease dissolving oxygen in the1

Japan Atomic Energy Agency (JAEA)
Osaka University
3
RIKEN
4
Universität Mainz
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JAEA-Review 2010-056

solution. The potentials applied to the electrode were 0 V and -0.9 V vs. an Ag/AgCl reference electrode in
1.0 M LiCl. The 0.1 M HCl effluent from the column working electrode was collected on 5 Ta disks. In
another experiment, we verified that divalent ions such as Sr2+ and Eu2+ are eluted with 0.1 M HCl while
trivalent ions of lanthanides are adsorbed on the working electrode under the given conditions. The
adsorbed ions on the electrode were then stripped with 3.0 M HCl and the effluent was collected on
separate 2 Ta disks. These 7 effluent samples were subjected to -spectrometry with 7 Si detectors after
evaporated to dryness with a halogen lamp and burned off with a burner.
Figure 1 shows a typical -spectrum observed in the experiment with the 61.2-MeV 11B4+ beam in the
middle of the target. The -peak of 255Md is clearly found at the energy of ~7330 keV. Alpha-peaks of 211Po,
254

Fm, and 252,255Fm are also observed. We determined a half-life of 255Md to be 29 ± 2 min by measuring

the dried samples after the HDEHP separation in the chemical experiment totally for 5.8 hours. The present
half-life value agrees well with the previous ones (27 ± 2 min) [2, 3] within statistic errors, representing nocontamination from by-products in the energy region of interest. Figure 2 shows the excitation function of
the 248Cm(11B, 4n) reaction. Curves show results of a calculation with the HIVAP code [4] for the
production of Md isotopes in the 248Cm + 11B reactions. The measured peak of the excitation function for255

Md is at around 58 MeV which is slightly higher than the energy expected with the calculation.

In the electrochemical experiment, it was found that 255Md is completely adsorbed on the working electrodein eluting 0.1 M HCl at the applied potential of 0 V. This behavior was the same as that of 250Bk3+ which
was a by-product of the nuclear reactions, showing no reduction of Md3+ at the given potential. On theother hand, at -0.9 V, Md was eluted with 0.1 M HCl, which was quite similar to the behavior of Sr2+ andEu2+ in our previous experiment. Therefore, it was found that Md3+ is successfully reduced to Md2+ with the

Cross section / b

Md (7327)
Po (7450)255

Fm (7192)

50
0
7000

101
255Md

253Md

254Md

100

10-1

256Md

211

100

254

150

252

200

Fm (7039) +Counts / 10 keV

250

255

300

Fm (7022)

electrochemistry apparatus. In the near future, we will determine the redox potential of Md.

7200

7400
7600
Energy / keV

7800

10-2
45

50

55

60
65
Elab / MeV

70

75

Fig. 2 Excitation function of the 248Cm(11B,4n)255Md reaction. Curves show results with
the HIVAP code.

Fig. 1 Alpha spectrum observed in theexperiment with the 61.2-MeV 11B beam.
References[1] A. Toyoshima et al., Radiochim. Acta, 96 (2008) 323-326.
[2] P. R. Fields et al., Nucl. Phys., A154 (1970) 407-416.
[3] R. W. Hoff et al., Nucl. Phys., A169 (1971) 641-650.
[4] W. Reisdorf and M. Schädel, Z. Phys. A343 (1992) 47-57.

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JAEA-Review 2010-056

4.3

On-line isothermal gas chromatographic behavior of group-5 elements as
homologues of Db
1

1

1

1

1,2

1

T. K. Sato , K. Tsukada , M. Asai , A. Toyoshima , N. Sato1,
Z.J. Li , T. Kikuchi, S. Liang1 and Y. Nagame

1

Dubnium (Db, Z = 105), one of transactinide elements dubnium, is expected to be a member of group-5 anda homologue of V, Nb, and Ta according to its place in the Periodic Table. In the gas phase the group-5
elements are most stable in their maximum oxidation state of +5 and therefore form pentachlorides inatmosphere.

pentachlorides,
Oxychlorides

Besidesthearestable.

oxychlorides
are

less

volatile

than

The chemical properties of Db compounds ingas phase have been still ambiguous since it
was only reported that the retention behavior of
of

Db

in

an

isothermal

(a)
88

the

pentachlorides.

chlorides

15

gas

Nb

Overall eff./ %chlorinating

10

5

chromatography had two components at least

170

Ta

owing to contamination of oxygen would leadproduction

of

both

pentachloride

and

0
20

oxychloride simultaneously [1]. In this work,
we performed the on-line experiments withhomologues of Db in gas phase with anapparatus we have developed under conditions
to form only oxychloride species in order tocompare volatilities of the same species among

88

Nb

Overall eff./ %short-lived Nb and Ta isotopes as the

(b)

10

Db, Nb and Ta, each other.

170

Ta

Short lived Nb and Ta isotopes were producedin the reactions ofnat

Ge (19F, xn)

88(T1/2=14.5 min) and

nat

19

170

Gd ( F, xn)

0Nbfacility.

The

400

600

Ta

Isotherm. temp/ °C(T1/2=6.7 min), respectively at the JAEA
Tandem accelerator

200

on-lineFig. 1 Overall efficiencies observed for 88Nb (○) andisothermal gas chromatographic apparatus was

170

directly connected to a target chamber forwith (a) 5% and (b) 2% of oxygen concentration as

efficient transportation of nuclear reaction

reactive gas are shown as a function of the isothermal

Ta (●) with 200 ml min N2 saturated SOCl2 vapor

column temprature.
1
2

Japan Atomic Energy Agency (JAEA)
Ibaraki University- 69 -

JAEA-Review 2010-056

products recoiling out of the target from the chamber to the apparatus by the He carrier gas flow. To
optimize ranges of the nuclear reaction products, nitrogen gas was added to the He carrier gas. In thereaction room of the apparatus, the transported products were stopped on quartz wool where a reactive gas
was introduced. Nitrogen saturated with SOCl2 vapor with 5 % or 2 % oxygen concentration was used as
the reactive gas to produce the volatile oxychlorides of the Nb and Ta. Volatile species produced in thereaction room were then transported along the isothermal column by the carrier gas flow. At the end of theisothermal column, volatile compounds leaving the column were attached to KCl aerosol particles in a
gas-jet chamber and transported to a detection system. An HP-Ge detector was used to measure the -raysof each nuclide. We measured yields of the volatile compounds of 88Nb and 170Ta pass through the column
as a function of isothermal temperature. These results were compared with direct measurements of therecoil products from the target using an Al catcher foil before chemical separation.
Figure 1 shows the variations of the overall efficiencies of Nb and Ta as a function of isothermal
temperature for 5% and 2% of oxygen concentration in the reactive gas. The efficiencies for 5% oxygen
were lower than those in the case of 2%. The maximum efficiency of Nb for 2% oxygen in the reactive gas
reached about 18 % and that of Ta about 10 % while the maximum of Nb for 5 % oxygen was about 13 %and that of Ta was about 7 %.

The each behavior of Nb and Ta had only one component and was notchanged between the both conditions of oxygen concentration. The Nb behavior was similar to thatreported in the previous work in which HCl was used as a chlorinating agent with He carrier gas containing
about 100 ppm of oxygen [2]. Therefore, in these conditions, only one volatile species of Nb might beformed. The chemical species would be identified as NbOCl3 based on its volatility. According to thesimilarity with Nb, the Ta behavior would be due to TaOCl3 in this experiment. These results showed thevolatility of the Ta compounds is lower than that of Nb.
References[1] A.Türler et al., Radiochim. Acta, 73 (1996) 55.
[2] H. W. Gaggler et al., J. Radioanal. Nucl. Chem., 183 (1994) 261.

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JAEA-Review 2010-056

4.4

Gas-phase chemistry of Zr and Hf using carbon cluster transport system
S. Goto1, H. Murayama1, M. Murakami1, T. Kojima1, H. Kudo1,
K. Tsukada2, M. Asai2, T. K. Sato2, N. Sato2 and Y. Nagame2

A gas phase chemical separation has been applied to the investigation of chemical properties
of superheavy elements because it allows separating them continuously and rapidly. Adsorption
enthalpies of volatile compounds of these elements can be determined by their adsorption-desorption
processes on a surface of gas chromatograph column. In this study, we investigated gas chromatographic
behavior of volatile chloride compounds of Zr and Hf using a newly fabricated apparatus for the study ofRf.
The Zr and Hf isotopes were produced in the natGe and natGd(16O, xn) and natGe and natGd(18O, xn) reactions
at the JAEA tandem accelerator facility. Nuclear reaction products were transported to the gas
chromatographic apparatus with attaching on a carbon cluster in a He carrier gas flow. The transported
products were collected on a quartz wool plugged in a quartz tube where a reactive HCl gas was added toform volatile chloride compounds. The formed volatile compounds were then fed into an isothermal
chromatographic quartz column directly connected to the tube. The compounds of Zr and Hf through thecolumn were re-transported attaching on a KCl cluster in a He carrier gas flow, and collected in a glass
filter for γ-rays measurement to determine the yields of these elements which passed through the column.
The passed-through yields for Zr and Hf were obtained as a function of the temperature of the isothermalcolumn.
It was found that isothermalchromatographic behavior of Zr and Hf was similar with each other. The yields
of both the elements increased with the temperature of the column between 300 and 450 oC. The behaviorof Zr was almost the same as that of our previous report [1]. The overall efficiency to re-transportation was
about 10% for Zr sat 450 oC of column temperature. It will be enough efficiency for Rf experiment.

References[1] T. K. Sato et al., J. Nucl. and Radiochem. Sci., 6 (2005) N1–N3.

1
2

Niigata University
Japan Atomic Energy Agency (JAEA)- 71 -

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JAEA-Review 2010-056

CHAPTER 5
Nuclear Theory

5.1

Analysis of surrogate reaction with unified model

5.2

Shell-model description of multi-particle multi-hole states around 16O andthe role of correlation energy

5.3

Verification of the surrogate ratio method

5.4

New formulation with CDCC
for evaluating incomplete and complete fusion cross sections

5.5

Competition between allowed and first-forbidden transitions of beta decay
in the neutron-rich mass region relevant to the r-process nucleosynthesis- 73 -

This is a blank page.

JAEA-Review 2010-056

5.1

Analysis of surrogate reaction with unified model
Y. Aritomo1, S. Chiba1 and K. Nishio 1

A proper description of nuclear fuel cycles for energy applications requires nuclear data on various types ofcompound reaction. Often the cross section needed for a particular application cannot be measured directly,
as the relevant energy region is inaccessible or the target is too short-lived. To overcome the experimental
limitations, indirect methods have to be developed, such as the surrogate nuclear reaction approach. To
create the desired compound nucleus, we employ a different reaction with a more experimentally accessiblecombination of projectile and target. At energies below 1 MeV, it is considered that mismatches in thecompound nucleus spin-parity distributions between the neutron-induced and surrogate reactions can affectthe interpretation of a surrogate measurement.
To understand the reaction mechanism and clarify such mismatches, it is indispensable to establish atheoretical model to describe the whole process in surrogate reaction. Here, we try to apply the unified
model to the surrogate reaction. The unified model has been developed by FLNR theoretical group in
Dubna. This calculation model can treat all reaction processes in heavy- and superheavy-mass regions,which has been applied to several types of reactions [1, 2]. The unified model implies an unified dynamical
approach and unified multidimensional potential energy [1]. We then perform a trajectory calculation on thetime-dependent unified potential energy surface using the Langevin equation. Thus, the whole evolution of
the heavy nuclear system can be traced starting from the infinite distance between the projectile and target
to the end of each process.
We take into account the time evolution from the diabatic potential Vdiab(q) to the adiabatic potential
Vadiab(q), here q denotes the collective coordinates of nuclear deformation. The diabatic potential iscalculated by the folding procedure with effective nucleon-nucleon interaction [1, 2]. We use the adiabatic
potential energy of the nuclear system calculated using the two-center shell model. We connect the diabatic
potential and adiabatic potential with a weight function as follows; V = Vdaiab (q) f (t) + Vadiab(q) [ 1 – f (t) ] ,f (t) = exp ( - t/τ). Here, t is the time of interaction and f (t) is a weight function on the relaxation timeτ.
We use the relaxation timeτ=10-21 s, which was suggested in references [3]. As the coordinates of nuclear
deformation, we use the two-center parametrization [4, 5] and employ three parameters: z0 (distance
between two potential centers), δ(deformation of fragments), and α(mass asymmetry of the colliding
nuclei) defined by α=(A1-A2) /ACN, where A1 and A2 denote the mass numbers of the target and the
projectile, respectively. ACN denotes the mass number of the compound nucleus. We perform the trajectory
calculation on the time-dependent unified potential energy using the Langevin-type equation. The
multidimensional Langevin equation is described precisely in reference [1, 6].

1

Japan Atomic Energy Agency (JAEA)- 75 -

JAEA-Review 2010-056

0= 2,

8.0x103

Ecm=160 MeV

0= 2, tan=10,

6.0x10318

2n transfer

tan= 118

tan= 56.0x103 tan= 1

tan=10

Counts104.0x103

O + 238U
O + 236U

4.0x103tan=20

5CountsEcm=160 MeV

238

2.0x10

U

240

U

3

20

2.0x103

0.0

0.0

0

2

4

6
J

8

10

0

12

Fig. 1 Spin distribution of compound nucleus 240U
in the reaction 18O+238U  16O+240U at the incident
energy of Ec.m. =160 MeV for several sliding
friction.

2

4

6
J

8

10

12

Fig. 2 Spin distribution of compound nucleus
240
U and 238U in the transfer reactions 18O+238U
 16O+240U at the incident energy of Ec.m. =160
MeV 18O+236U  16O+238U, respectively.

Recently, the surrogate ratio method is discussed and it was found that we need not know the spin-parity
distributions populated by surrogate reaction, if (1) there exist two surrogate reactions whose spin-parity
distributions of decaying nuclei are almost equivalent, and (2) difference of representative spin values
between the neutron-induced and surrogate reactions is not much larger than 10ℏ [7]. Using our theoreticalmodel, we calculate the spin of compound nucleus in surrogate reactions. Here, as an example of thesurrogate reaction, we consider the two neutron transfer reaction; 18O+238U  16O+240U. Figure 1 shows
the spin distribution of compound nucleus 240U at the incident energy of Ec.m. =160 MeV. In the Langevincalculation, the sliding friction is mainly responsible for the dissipation of the angular momentum [1],though the value has uncertainty. We treat the sliding friction γtan as a parameter of the model. The unit offriction is 10-22 MeV s fm-2. We can see the spin of compound nucleus is less than 10 ℏ for each value of
sliding friction. Figure 2 shows the spin distribution of compound nucleus 240U and 238U in the transfer
reactions 18O+238U  16O+240U and 18O+236U  16O+238U, respectively. We use the sliding frictionγtan=10×10-22 MeV s fm-2. The spin distributions of decaying nuclei by two reactions are almost equivalent.
Such calculation results suggest the validity of the surrogate ratio method.
References[1] V. Zagrebaev and W. Greiner, J. Phys., G31 (2005) 825.
[2] V. Zagrebaev and W. Greiner, J. Phys., G34 (2007) 1; J. Phys. G34., (2007) 2265; Phys. Rev. Lett., 101(2008) 122701; Phys. Rev., C78 (2008) 034610.
[3] G.F. Bertsch, Z. Phys., A289 (1978) 103 (1978); W. Cassing and W. Norenberg, Z. Phys., A401 (1983)
467; A. Diaz-Torres, Phys. Rev., C69 (2004) 021603 (2004).
[4] J. Maruhn and W. Greiner, Z. Phys., 251 (1972) 431.
[5] K. Satoet al., Z. Phys., A288 (1978) 383.
[6] Y. Aritomo, Phys. Rev., C80 (2009) 064604.
[7] S. Chiba and O. Iwamoto, Phys. Rev., C81 (2010) 044604.

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JAEA-Review 2010-056

5.2

Shell-model description of multi-particle multi-hole states around 16O and the roleof correlation energy
Y. Utsuno 1 and S. Chiba1

Around oxygen isotopes, many low-lying states are known which cannot be described by the simple shellmodel assuming 16O as an inert core. They are considered to be states dominated by a multi-particle
multi-hole excitation across the N or Z=8 shell gap. For instance, the 0+2 state of 16O, located at only 6.05
MeV, is widely accepted to consist predominantly of four-particle four-hole (4p-4h) configurations in spiteof the existence of a large N or Z=8 shell gap ~10 MeV.
The large-scale shell model, in which particle-hole excitations from the p- to sd-shell are taken into account,
is a promising method to describe the multi-particle multi-hole states microscopically. Previous shell-modelstudies [1, 2] included configurations up to 4hω excitation from the lowest, and succeeded in reproducing
some multi-particle multi-hole states of 16O by adjusting the N(Z)=8 shell gap. The resulting shell gap was
however considerably smaller than the standard value, and the reason for that has not been clarified. The
aim of the present study is giving a more comprehensive picture about the interplay between the shell gap
and the multi-particle multi-hole states on the basis of the shell model. This should be of great help to thedescription of transfer reactions using oxygen beam.
We first revisit the shell gap. The single-particle
energy is often associated with the experimental
separationenergydirectly.

The

standard

single-particle energy for the shell model is sodetermined, too. This works well if the ground stateof 16O is a complete closure without correlationenergy. In order to evaluate the effect of correlationenergy, we carry out shell-model calculations
assuming the full p-sd shell as the valence shell. We
use the PSDWBT interaction [3] as the effective
interaction.

Figure

1

shows

the

cross-shell16

correlation energy for nuclei around O. Here, thecross-shell correlation energy is defined by the Fig. 1 Cross-shell correlation energies forenergy difference between that calculated in the full 15,16,17O and 20Ne.

12C,

p-sd model space and that calculated withoutcross-shell excitation. The cross-shell correlation energy maximizes at 16O. Namely, the one-neutron
separation energy of 17O, E(16O)-E(17O), enlarges, while that of 16O reduces. This indicates that thesingle-particle energy of the sd shell must be lowered and that of the p shell must be raised when the1

Japan Atomic Energy Agency (JAEA)- 77 -

JAEA-Review 2010-056

correlation energy is taken into consideration.
Based on the above discussion, we next construct a Hamiltonian with the “correct” single-particle energy:
the single-particle energies and the overall strength of the p-shell and sd-shell interaction are adjusted sothat the calculation can reproduces the energies sensitive to the shell gap, i.e., those of the 5/2+1, 1/2+1 and3/2+1 of 17O, those of 1/2-1 and 3/2-1 of 15O, and the ground-state energies of 20Ne and 12C. Figure 2 shows apartial level scheme of 16O compared between experiment and calculation. Not only negative-parity states
dominated by 1p-1h states (located ~6-10 MeV) but also members of 4p-4h states (0+ to 6+) are in good
agreement between experiment and calculation. We stress that the shell gap used in this study is determined
to reproduce the energy around the ground state but not to fit the multi-particle multi-hole state directly.
When the original PSDWBT interaction is used, the 0+2 of 16O appears around 12 MeV. Thus, therenormalization of single-particle energy is essential to describe the multi-particle-multi-hole states.

Fig. 2 Energy levels of 16O compared between experiment (left) and calculation (right).

References[1] W.C. Haxton and C. Johnson, Phys. Rev. Lett. 65 (1990) 1325-1328.
[2] E.K. Warburton, B.A. Brown, and D.J. Millener, Phys. Lett. B293 (1992) 7-12.
[3] E.K. Warburton and B.A. Brown, Phys. Rev. C46 (1992) 923-944.

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JAEA-Review 2010-056

5.3

Verification of the surrogate ratio method
S. Chiba1 and O. Iwamoto 1

With the advance of nuclear science and technology, neutron cross sections of unstable nuclei, such as
minor actinides (MAs) and long-lived fission products (LLFPs), are becoming more and more necessitated.
Neutron cross sections of radioactive nuclei also play important roles in astrophysical nucleosynthesis. In
spite of the importance, however, measurement of neutron cross sections is extremely difficult for these
nuclei since preparation of sample is difficult or practically impossible. At the same time, theoretical
determination of the fission and capture cross sections still suffers from a large uncertainty if there exists noexperimental data; an error of factor of 2, namely the uncertainty of 100 %, will be a reasonable estimate.
These fundamental problems prevent us from accurate determination of neutron cross sections of unstable
nuclei including MAs and LLFPs.
Recently, a new method, called the surrogate method, has come to be used actively to determine neutron
cross sections of unstable nuclei. This is a method which uses (multi) nucleon transfer reactions (bothstripping and pick-up) or inelastic scattering on available target nuclei and produce the same compound
nuclei as those of the desired neutron-induced reactions, and measure the decay branching ratios leading tocapture and/or fission channel. Identification of the produced compound nuclei and their excitation energies
can be done by detection of the ejectile species and their energies.
At a first glance, it seems to be a simple and effective method to simulate the neutron-induced reactions.
However, the thing is not easy. Even if we produce the same compound nuclei at the same excitationenergy as produced in the desired neutron-induced reactions, the spin-parity distributions are plausibly
different between them. Since we are interested in low-energy neutron cross sections relevant to reactor
applications and astrophysics, the produced compound nuclei decay statistically, and the branching ratio isstrongly influenced by the spin and parity. Therefore, difference of the spin-parity distributions between thesurrogate and neutron-induced reactions must be properly taken into account in converting the branchingratio determined by the surrogate method to the one for neutron-induced reactions. Up to now, however, it
has not been able to deduce the spin-parity distribution in the surrogate reactions, since they are normally
multi-nucleon transfer reactions, the reaction mechanisms of which are not understood well.

On theother hand, it is also true that the surrogate method has yielded rather accurate cross sections, verified when
the corresponding neutron data are available. Therefore, it is natural to expect that there is a certain
condition to equate the results from the surrogate method and the neutron-induced reactions. However, thecondition under which the surrogate method works is not clearly understood yet.
In this work, we investigate the spin-parity dependence of the branching ratios of Uranium and isotopes
around mass 200 to the fission and capture channels and clarify the condition for the surrogate ratio method
1Japan Atomic Energy Agency (JAEA)- 79 -

JAEA-Review 2010-056

to work, and estimate the accuracy achievable by it.

Jπ-by-Jπ ratio of the branching ratios

Fig. 1 J-dependence of the branching ratio toFig. 2the capture channel from the positive-parity

to the capture channel for 238U+n and 236U+n

states produced in neutron capture by 238U.

reactionsFigure 1 shows the decay branching ratio to the capture channel from various spin (J) states in thecompound nucleus produced by capture of neutrons by 238U calculated by a statitical model[1,2].
apparent that the branching ratio depends strongly on the J value of the decaying states.
around a factor of 5 even at neutron energy of 5 MeV where it is minimal.

It is

The deviation isThis fact shows that differenceπof the J distribution produced in the neutorn-induced reactions and the surrogate reactions might affect the
net decay branching ratios.

This difference would cause the results of both reactions quite different fromeach other, thus deteriorating the usefulness of the surrogate method.

On the other hand,the branching ratio (capture probability) is monotonic as a function of the spin values.
same tendency in the neutron-induced reactions of a neighboring nucleus

236

U.

the change ofWe also notice theSince such a tendency was

found also other combinations of nuclei around A = 200, we may expect that there is a possibility to cancelout the apparent Jπ dependence in the branching ratio by taking ratios of them for each Jπ. Results ofsuch a calculation are shonwn in Fig. 2, where the ratios of decay branching ratio to capture channel for
238

U+n and 236U+n reactions are shown for various J+ values.

We notice that this quantity shows adrastically good convergence. The factor of 5 difference in Fig. 1 is now reduced to around 10% above 2
MeV except for J π value of 21/2+.

Furthermore, these ratios nicely coincide with that of theneutron-induced reaction which is shown by the thick solid line in Fig. 2.
for the fission channels.

The coincidence is even better

From these conciderations, we can conclude that the surrogate ratio method canyield the correct neutron cross section ratios if 1) such a coincidence as shown in Fig. 2 is realised, 2) the
spin-parity distributions used in the two surrogate reactions are equivalent to each other, and 3) J values
larger than 10 is not the major component[3].

Validity of these conditions can be verified by measuring

the angular and energy distributions of emitted particles (such as protons in (t,p) reaction) or photons.
References[1] W. Hauser and H. Feshbach, Phys. Rev., C87 (1952) 366.
[2] O. Iwamoto, J. Nucl. Sci. Technol., 44 (2007) 687.
[3] S. Chiba and O. Iwamoto, Phys. Rev., C81 (2010) 044604.

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JAEA-Review 2010-056

5.4

New formulation with CDCC for evaluating incomplete
and complete fusion cross sections
S. Hashimoto 1 , K. Ogata 2 , S. Chiba1,3 and M. Yahiro2

The interest of breakup effects on the fusion reaction has grown recently. Incomplete fusion processes, inwhich a part of the projectile is absorbed by the target with emitting the other fragment(s), play animportant role in studying the reaction with weakly-bound nuclei. For deuteron induced reactions, theknowledge about the reaction mechanism and nuclear data of (d,n) reactions on various targets are required
for studies on nuclear applications such as the International Fusion Materials Irradiation Facility (IFMIF).
The inclusive (d,n) reaction on Li targets at incident energy 40 MeV is analyzed by Ye et al. [1], and they
showed that contributions of the incomplete fusion reaction to the observables are very large. In Ref. [1],the incomplete fusion process is described by the Glauber model, and the result reproduces very well theexperimental data added by elastic breakup contributions obtained with the Continuum-Discretized
Coupled-Channels method (CDCC) [2]. Nevertheless, it is important to test the validity of the Glaubermodel in the low energy region by comparing it with that obtained fully quantum mechanically.
We propose a new approach [3] for evaluating cross sections of the incomplete and complete fusions using
CDCC, which takes into account the effect of the breakup on the reaction and has been successfully applied
to analyze various reactions with weakly-bound nuclei. Since imaginary parts of p-Li and n-Li opticalpotentials Wc (c=p and n) describe absorption (fusion) of the particle c, the total fusion cross section is
given as tot . fu .   drp drn  * (rp , rn )(W p (rp )  Wn (rn )) (rp , rn ) ,(1)

where Ψ is the wave function in the framework of the three-body system, and rp (rn) is the coordinate of p(n) to the target. Using an absorption radius rcab, which is an effective range of Wc, the integration intervals
in Eq. (1) can be divided into four regions shown in Fig. 1. The contribution of the left-lower region, in
which both p and n are located within the range of Wc and absorbed by the target, corresponds to thecomplete fusion process. In the right-lower region, n is assumed to be within the range of Wn, while p isfree of the absorption. Then, the contribution of the region corresponds to the (d,n) incomplete fusion
process. Similarly, that of the left-upper region corresponds to the (d,p) incomplete fusion. Therefore, we
can obtain each fusion cross section by the integration over the region corresponding to the process.
This method is applied to analysis of the deuteron induced reaction on a 7Li target up to 50 MeV of thedeuteron incident energy EdL using CDCC codes [4]. In Fig. 2, results of the method are compared withthose of the Glauber model. The panel a) shows the two incomplete fusion cross sections ((d,n) and (d,p))
calculated with the Glauber model and those with the new method, in which we used rcab=4.0 fm
1

Japan Atomic Energy Agency (JAEA)
Kyushu University
3
National Astronomical Observatory of Japan2- 81 -

JAEA-Review 2010-056

determined by a condition that the result of (d,n) at 40 MeV obtained by the the present calculation agrees
with that obtained by the Glauber model. It is found that for the incomplete fusion processes the Glaubermodel reproduces the results of the new method below 40 MeV, and works well. On the other hand, for thecomplete fusion a comparison between results obtained with our method and those with the Glauber modelis shown in the panel b) of Fig. 2. One sees that the two models give significantly different results of evenat 50 MeV.
In conclusion, we proposed a new method to evaluate the incomplete and complete fusion cross sections bymeans of CDCC, and applied to the analysis of the deuteron induced reaction on the Li target. Comparing
the results obtained by the new method with those by the Glauber model, we found that the Glauber model
describes the incomplete fusion process very well below 50 MeV, while for the complete fusion the twomodels give markedly different energy dependence. In order to investigate the reaction mechanism in detail,the development of the formulation is necessary to calculate the angular differential cross section or theenergy spectrum of the reaction.

a Incomplete fusion

600(d,n),This work

 [mb](d,p),This work(d,n),Glauber model

400(d,p),Glauber model200

 [mb]

0This workb Complete fusion

400

Glauber model

200
0

0

10

20

30

40

50

ELd [MeV]

Fig. 1 Schematic illustration of divided
integration intervals corresponding to eachfusion reaction.

Fig. 2 Incomplete and complete fusion crosssections of d on 7Li as a function of incident
energy EdL calculated with the new method
and the Glauber model.

References[1] T. Ye, Y. Watanabe and K. Ogata, Phys. Rev., C80 (2009) 014604.
[2] M. Kamimura et al., Prog. Theor. Phys. Suppl., 89 (1986) 1.
[3] S. Hashimoto et al., Prog. Theor. Phys., 122 (2009) 1291-1300.
[4] Y. Iseri et al., Bull. Res. Comput. Syst. Comput. Commun. Cent. Kyushu Univ. Vol. 5, No. 3, (2006)
117-134 (CDCDEU); Vol. 1, No. 1, (2007) 16-28 (HICADEU).

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JAEA-Review 2010-056

5.5Competition between allowed and first-forbidden transitions of beta decay in theneutron-rich mass region relevant to the r-process nucleosynthesis
H. Koura 1

Beta decay in the neutron-rich mass region plays an important role on the r-process nucleosynthesis.

Mostof these nuclei are unknown or little nuclear data exists still now, so theoretical estimation is essentiallynecessary to study it.

In some theoretical approaches, however, only the allowed transitions as the Fermi

and the Gamow-Teller transition are considered, and no forbidden transitions are treated.

In this report,

we estimate the beta decay rate in the framework of the first version of the gross theory[1], and evaluate an
influence of the first-forbidden transition in the neutron-rich mass region.
Generally, beta-decay rate up to the first-forbidden transition is expressed as(1)(2)
  F  GT  (0)1  1  1 .

(1)Here subscripts stand for Fermi, Gamow-Teller and first-forbidden transition, and superscripts in thefirst-forbidden represent the rank L=0, 1 and 2, respectively.

According to the V-A beta-decay theory,

decay constant (or decay rate) is obtained from the nuclear matrix element |M(E)|2.

In the case of theGamow-Teller and the rank-2 first-forbidden transitions, the decay rates can be written as

GT 



me 5 c 4
2 0
2
3 7 g A Q M (E) f (E)dE
2 

(2)

2
me 5 c 4 me c 
2 0
 g A Q  M ij (E) f1 (E)dE .
3 7 
2     
ij

(3)

and
(2)

1 


2

Here. me is a rest mass of electron, gA is the axial-vector type coupling constant, f and f1 are the integrated
Fermi function of the allowed and the unique-first forbidden transition and Q is the beta-decay Q-value.
In the Gross theory, we assume the nuclear matrix element |M(E)|2 as an integral of a single-particle
strength function so as to fulfill the sum rules of |M(E)|2 and concentration (allowed) and non-concentration(forbidden) of the single-particle strength functions to isobaric analogue states.

The beta-decay Q-values

are obtained from the KTUY mass formula, which gives a good reproduction of ground-state nuclear
masses, derivatives of masses as neutron, proton separation energies for known nuclei[2].
Due to the smallness of F compared to GT in the neutron-rich mass region excepting the quite light region
like neutron and 3H, we only compare the decay constants of the Gamow-Teller transition and the sum of
the first-forbidden transition.

Fig. 1 shows the dominant decay modes in the neutron-rich mass region.

In many cases the Gamow-Teller transition rate is larger (or the partial half-life is longer) than thefirst-forbidden transition in the neutron-rich side. In the stable and rather neutron-rich region heavier than
1

Japan Atomic Energy Agency (JAEA)- 83 -

JAEA-Review 2010-056

nuclei around 132Sn82, however, the area of nuclei with larger rate of the first-forbidden transition than thatof the Gamow-Teller spreads widely. If we consider the evolution of the simple single-particle levels to
the neutron-rich side from 208Pb126 as shown in Fig. 2, such a properties can be roughly discussed.
case of the single-particle levels of the stable isotone of N=126,

In the208

Pb, there seems to be no allowedtransition channel due to the hindrance from the selection rule of angular momentum and parity, andconsequently the first forbidden transition is dominant.

In the case of 192Dy, however, some allowedtransition channels are open, and the strength of the allowed transition may be comparative or larger than
the forbidden transition.

GT>1st (GT dom.)GT<1st (1st dom.)stable against -decay

80
Proton number Z

This property also supports the result of beta-decay rates in this report.

60
40
20
0

Gross theory 1st ver.+KTUY mass
1/3
Q>10/A
0

20

40

60

80
100
120
Neutron number N

140

160

180

2009.7.2 H.K

Fig. 1 Dominant transition mode between the Gamow-Teller and the first-forbidden transition of the beta
decay in the neutron-rich mass region.

0-4

2f7/2 (p)1h9/2 (p)208

Pb

Neutron(82,126)
3p1/2 (n)-6 3s1/2 (p)2f5/2 (n)2d3/2 (p)
-8 1h
(p)

3p3/2 (n)-10 2d5/2 (p)1i13/2 (n)

11/2

-12

1g7/2 (p)-14

2f7/2 (n)1h9/2 (n)3s1/2 (n)0Proton-2

200

W

Neutron(74,126)-4

2f7/2 (p)2f5/2 (n)3p3/2 (n)

-6
-8
-10
-12
-14

3p1/2 (n)1h9/2 (p)3s1/2 (p)2d3/2 (p)1h11/2 (p)2d5/2 (p)1g7/2 (p)1i13/2 (n)

1st
1st
GT

2f7/2 (n)1h9/2 (n)3s1/2 (n)Single-particle levels (MeV)

ProtonSingle-particle levels (MeV)

Single-particle levels (MeV)

0
-2

192

(66,126)

2f5/2 (n)3p3/2 (n)GT

1i13/2 (n)

-4
-6
-8

2f7/2 (n)1h9/2 (n)

-10
-12
-14
-16

1h9/2 (n)GT

3s1/2 (n)3s1/2 (n)F

2d3/2 (n)1h11/2 (n)2d5/2 (n)(forbidden trnas. are not shown)

1g7/2 (n)Fig. 2 Single-particle levels of N=126 isotones: 208Pb (left), 200W(middle), 192Dy (right).

2f7/2 (n)GTas odd-A nucleus

as odd-A nucleus

3p1/2 (n)Dy-2

as odd-A nucleus

We assume these

nuclei are spherical and calculate the levels from a modified Woods-Saxon type potential[3].
References[1] K. Takahashi, M. Yamada and T. Kondoh, At. Data and Nucl. Data Tables, 12 (1973) 101-142.
[2] H. Koura et al., Prog. of Theor. Phys., 113 (2005) 305-325.
[3] H. Koura and M. Yamada, Nucl. Phys., A671 (2000) 96-118.

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JAEA-Review 2010-056

CHAPTER 6
Atomic Physics and Solid State Physics

6.1

Coster-Kronig electron spectra of C- and N-like Oq+ (q = 1,2)

6.2

Charge state distribution of sulfur ions after penetration of C-foil targets

6.3

Li diffusion in Li ionic conductors of NaTl-type intermetallic compounds

6.4

Diffusion coefficient measurements on perovskite-type lithium ion conductor

6.5

High-energy ion impact effects on atomic structure and optical property of
In-doped ZnO films

6.6Electrical property modifications of In-doped ZnO films
by high-energy ion impact- 85 -

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JAEA-Review 2010-056

6.1

Coster-Kronig electron spectra of C- and N-like Oq+ (q = 1,2)

K. Kawatsura 1,2, K. Takahiro3, M. Sataka4 M. Imai5, H. Sugai4, K. Kawaguchi3,
T. Yoshimori3, H. Shibata5 and K. Komaki6

Recently we have reported on Coster-Kronig (C-K) electron spectra in high-energy collisions of 32 MeV
Oq+ (q = 3,4) ions with a He gas target [1,2]. For Be-like O4+ ions, a series of 1s22p(2P)nl – 1s22s(2S)l’ (n =6-11) C-K transitions was assigned. The high-resolution spectrum for the 1s22p6l state has shown that thepeak due to the low angular momentum l = 1 is the most intense, which obeys dipole selection rules. This
result for the l distribution has been found to be different from those of the double electron capture (DEC)processes. For B-like O3+ ions, a series of 1s22s2p(3P)nl – 1s22s2(1S)l’ (n = 5-11) C-K transitions was
assigned. The sharp lines on both sides of the cusp peak have been confirmed to be due to the very low
energy transition from the 1s22s2p(3P)5s state. It is also found that states with the angular momenta of l =0-3 are populated and the maximum intensity is attributed to the states with higher angular momenta l ≥ 2.
The C-K spectra were compared with those for the dielectronic recombination (DR) processes.
In the present study, we have systematically measured C-K electrons from high-Rydberg states produced inhigh-energy collisions of 30 MeV O2+ + He and 15 MeV O+ + He for extending the investigation of C-K
electron spectra past highly charged Oq+ (q = 3,4) ions. The experiments were performed at the tandem
accelerator facility at the Japan Atomic Energy Agency (JAEA) of Tokai, using the 20 MV tandem
accelerator. Fig. 1 shows high-resolution spectrum of electrons ejected in the collision of 30 MeV O2+ ionswith a He target. For this collision system, projectile O2+ ions have 6 electrons which are more than in theprevious experiments for O3+ and O4+ ions. To our knowledge there is no report on C-K electron spectra forsuch a complicated collision system. Fig. 1 shows the C-K electron spectrum from O2+ 1s22s2p2nl statesand other excited states which were produced by electron excitation/ionization processes during 30 MeV
O2+ + He collision. Here, we calculate ejected electron energies arising from the possible C-K transitions
using equation,
En = E – Q2Ry/n2(1),

where En is the C-K electron energy, n is the principal quantum number, E is the energy difference
between the initial and final states of the ion core configuration, taken from the compiled transition energy
tables [3], Q is the effective charge of the ion core (assumed to be q+1 for this case), and Ry is the Rydberg
energy (13.606 eV). In the figure, the representative peaks are assigned to a series of 1s22s2p2(4P)nl –1s22s22p(2P)l’ (n  4) C-K transitions and vertical bars in Fig. 1 indicate the line positions obtained byequation (1). In this spectrum, the transitions to the 2P1/2 and 2P3/2 final states are not resolved but some1

Kansai Gaidai University
Theoretical Radiation Research Laboratory
3
Kyoto Institute of Technology
4Japan Atomic Energy Agency (JAEA)
5
Kyoto University
6
National Center for University Entrance Examinations
2- 87 -

JAEA-Review 2010-056
10

2

10

2 4

8

n=4

5

2

6 7 8 ...

3 5

1s 2s2p ( S)nl

2+

30 MeV O + He

8Intensity (arb.units)

Intensity (arb. units)

1s 2s2p ( P)nl

6
4
2

+

n=3

4 5 67...

0

4

15 MeV O + He

6
4
2

0

0
0

2

4

6

8

10

12

14

16

18

20

Electron Energy (eV)

6

8

10

12

14

16

18

20

Electron Energy (eV)Fig. 1 Coster-Kronig electron spectrum ejected at
2+2Fig. 2 Coster-Kronig electron spectrum ejected aton He. The

0° in collisions of 15 MeV O+ on He. The verticalvertical bars indicate the positions of thebars indicate the positions of the 1s22s2p3(5S)nl

1s22s2p2(4P)nl Rydberg series.

Rydberg series.

0° in collisions of 30 MeV O

structures are recognized at each value of n, to which the angular momentum (l) distribution should be
responsible. Fig. 2 shows the measured electron spectrum resulting from the collisions of 15 MeV O+ ionson He. For this collision system, projectile O+ ions have 7 electrons which are even more than theabove-mentioned collision system of 30 MeV O2+ +He. This figure shows the complicated C-K electron
spectrum ejected from O+ 1s22s2p3nl states and other excited states which were produced by electron
excitation processes. Here, we calculate ejection energies for the possible C-K transitions by using equation(1), where Q is the effective charge of the highly exited O+ ion core (assumed to be +2 for this case),
adopting the values of E given by Ref. [3]. In the figure, the representative peaks are assigned to a seriesof 1s22s2p3(5S)nl – 1s22s22p2(3P)l’ (n  3) C-K transitions and vertical bars indicate line positions obtainedby equation (1). In this spectrum, difference among the transitions to final 3P0, 3P1 and 3P2 states is notobserved but structures in the peaks for each principal quantum number (n  3), up to the series limit of
7.48 eV (n  ), seem to reflect the angular momentum distribution. Moreover, some structures present in
the higher energy region between 8.0 and 16 eV could be assigned to a series of 1s22s2p3(3D)nl –1s22s22p2(3P)l’ and/or 1s22s2p3(3P)nl – 1s22s22p2(3P)l’ C-K transitions, whose series limits are 14.88 eV
and 17.65 eV, respectively. However, a comprehensive analysis for high-resolution measurements of C-K
electron spectra as well as precise theoretical calculations are needed to obtain more detailed information
about the production of high-Rydberg states and their decay processes in the high-energy collision regime.

References[1] K. Kawatsura et al., Nucl. Instrum. Methods Phys. Res., B205 (2003) 528-531.
[2] K. Kawatsura et al., Nucl. Instrum. Methods Phys. Res., B245 (2006) 44-46.
[3] NIST Atomic Spectra Database: http://www.physics.nist.gov/PhysRefData/ASD/(accessed 2010-05-05).

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JAEA-Review 2010-056

6.2

Charge state distribution of sulfur ions after penetration of C-foil targets
M. Imai 1 , M. Sataka2, H. Sugai2, K. Kawatsura3,4, K. Takahiro5,
K. Komaki6, K. Nishio2 and H. Shibata1

Following injection into matter, swift heavy ions change their charge states until they establish chargeequilibrium, in which increases and decreases in population of each charge state balance with each other,and the populations seem to remain unchanged. Charge state is one of the most important aspects of ionmatter interactions and affects various processes in matter, such as electron capture, ionization, andexcitation of projectile and target electrons, as well as consequent phenomena such as energy deposition
into the target, i.e. stopping of projectiles. Projectile charge state and its evolution are therefore essential to
the study of the penetration of swift ions in matter and the data of charge-state distributions for various
collision systems after exiting solid targets have been supplied [1], although the charge-state distributionchanges somewhat upon exiting the target foil. As has been presented in the previous annual reports [2], we
measured the exit charge state distributions for penetrations of S6+ S16+ ions through C-foil targets of 0.9
200 g/cm2 in thickness and performed calculations by ETACHA code [3] to succeed in reproducing theexperimental results, although ETACHA has been designed for higher energy region (>10 MeV/u) [4]. We
performed another simulation, in which the electron transfer cross sections  qq ' are calculated with codes
applicable to the present collision energy [5]. In this report, mean charge states and distribution widths
derived from our measurements at 2.0 MeV/u are presented as well as those from simulations.
The present experiments were performed at the LIR1–3 beam line of the 20UR Tandem Accelerator Facility.
A beam of 2.0 MeV/u (64 MeV) S6+ or S7+ ions was provided from the Tandem Accelerator within anenergy accuracy of 0.1%. A post-stripper C-foil of ~20 g/cm2, placed downstream from theenergy-analyzing magnet, was used to produce higher charge states up to 16+. It should be noted here thathigh-voltage terminal equipment of the Tandem Accelerator has been replaced to improve beamtransportation optics [6], enabling us to extract sufficient numbers of bare S16+ ions. Energy loss values atthe post-stripper foil were assumed to be at most 0.7% based on separate measurements of cusp electronenergies with zero-degree electron spectroscopy [7]. The Sq+ (q = 6−16) ion beam was directed toself-supported carbon foil targets of 0.9−200 g/cm2 in thickness. The charge-state distributions after foil
penetration were measured using the heavy ion magnetic spectrometer ENMA and a position-sensitive gaschamber detector. The vacuum conditions inside the collision chamber and the spectrometer weremaintained below 104 and 106 Pa, respectively, to practically eliminate background charge-exchange
collisions with residual gas, which was confirmed by measurements without a target foil.

1

Kyoto University
Japan Atomic Energy Agency (JAEA)
3
Kansai Gaidai University
4
Theoretical Radiation Research Laboratory
5
Kyoto Institute of Technology
6
RIKEN
2

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JAEA-Review 2010-056
The values of mean charge states q   q qF  q  , where F(q) denotes the fraction for charge state q, areplotted in Fig. 1(a), with those derived by solving rate equations for charge state fractions in Fig. 1(b).

Mean Charge

14

12

(a)
10
16+

16

15+

Mean Charge

14+
13+

13

12+
11+
10+

10

9+
8+
7+

(b)
7
0.1

1

10

100

1000

Target Thickness (g/cm2)
Fig. 1

Mean charge state (a) measured for 2.0 MeV/u S6+ − S16+ ion incidences after passing
through C-foil targets and (b) calculated by solving the rate equations accounting for singleelectron transfers for 2.0 MeV/u S8+ − S16+ ion incidences (full lines) with experimental
results for S7+, S12+, and S14+ − S16+ ion incidences (filled symbols).

References[1] A. B. Wittkower and H. D. Betz, At. Data Nucl. Data Tables、5 (1973) 113-; K. Shima et al., ibid.
51 (1992) 173-; K. Shima et al., Nucl. Instrum. Methods Phys. Res., B33 (1988) 212-.
[2] M. Imai et al., JAEA-Review 2007-046 (2008) 87-; 2008-054 (2008) 89-; 2009-036 (2009) 91-
[3] J. P. Rozet et al., J. Phys., B22 (1989) 33; Nucl. Instrum. Methods Phys. Res., B107 (1996) 67-.
[4] M. Imai et al., Nucl. Instrum. Methods Phys. Res., B230 (2005) 63-.
[5] M. Imai et al., Nucl. Instrum. Methods Phys. Res., B256 (2007) 11; ibid. B267 (2009) 2675-.
[6] M. Matsuda et al., J. Phys., Conf. Ser., 163 (2009) 012112 (4 pp.).
[7] M. Sataka et al., Phys. Rev., A65 (2002) 052704 (11 pp.); M. Imai et al., Nucl. Instrum. Methods Phys.
Res., B67 (1992) 142-.

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JAEA-Review 2010-056

6.3

Li diffusion in Li ionic conductors of NaTl-type intermetallic compounds
H. Sugai 1 , M. Sataka1, S. Okayasu1, S. Ichikawa1, K. Nishio1, S. Mitsuoka1,
S.C. Jeong 2 , I. Katayama2, H. Kawakami2, Y.X. Watanabe2,
H. Ishiyama2, N. Imai2, Y. Hirayama2, H. Miyatake2, T. Hashimoto 3 and M. Yahagi3

Non-destructive and on-line Li diffusion experiments in Li-ionic conductors are conducted using theshort-lived -emitting radiotracer of 8Li. Li-8 decays through -emission to 8Be with a half lifetime of
0.84s, which immediately breaks up into two -particles with energies broadly distributed around 1.6MeV
with a full width at half maximum of 0.6MeV. The radiotracers produced as an energetic and pulsed ion
beam (typically 4MeV with an intensity of 104 particles/s) from TRIAC [1] (Tokai Radioactive Ion
Accelerator Complex) are implanted into a structural defect mediated Li ionic conductor of NaTl-type
intermetallic compounds. The experimental time spectra of the yields of -particles are compared withsimulated results and Li diffusion coefficients in the samples [1] are extracted directly. After a series ofexperiments of LiGa, the experiments of LiIn was conducted in fiscal 2009. In this report, thetemperature-dependence of diffusion coefficients obtained for LiIn with the Li content of 48 at.% arepresented and the thermodynamic properties of Li vacancies in LiIn are discussed [1].
The crystal structure of Ia-IIIb intermetallic compounds (e.g., LiAl, LiGa and LiIn) is NaTl-type [2,3],
which is composed of two interpenetrating diamond sublattices such that each atom has eight nearest
neighbors: four like and four unlike atoms. The characteristic defect structure of LiA (A=Al, Ga, In)consists of two types of defects at room temperature, i.e. vacancies in the Li sublattice (VLi) and Li
antistructure atoms in the A sublattice (LiA). For example, the concentrations of the point defects, [VLi] and[LiGa], strongly depends on Li content; with increasing the Li content from 43 to 54%, [VLi] decreases from
11.4 to 2.8%, while [LiGa] increases from 0 to 5.1% [4]. VLi is the dominant defect for the Li-deficientregion, while LiGa is the dominant defect for the Li-rich one. As mentioned above, we can control theLi-vacancy concentration which is a dominant path for the Li diffusion in the NaTl-type compounds withchanging the Li content. Thus, the NaTl-type compounds provide a useful and suitable field to study the Li
diffusion mechanism in Li-ionic conductors, which are key materials for Li-ion batteries.
The diffusion coefficients of Li and the electrical resistivity in LiIn of 48 at.% Li and in LiGa of 44 at.% Liare shown in Fig. 1 as a function of inverse temperature. The diffusion coefficients of Li in the LiGa of 44
at.% Li follow Arrhenius behavior in the region of higher temperature with an activation energy of 0.16 eV
well consistent with the value in the reference [5]. In the lower temperature followed by a sudden changearound 234K, the diffusion coefficients are observed as a constant, which is the lower limit of diffusion
coefficients accessible by the present method; for the diffusion coefficients less than about 10-10 cm2/s, any
significant effect in the yields of alpha-particles due to the diffusing 8Li could not be observed because of1

Japan Atomic Energy Agency (JAEA)
High Energy Accelerator Research Organization (KEK)3
Aomori University
2- 91 -

JAEA-Review 2010-056

the short lifetime of the radiotracer. The
sudden change in the value of the diffusion
coefficientaround234K occurs

at

the

temperature where the anomalous electricalresistivity is observed, as indicated by an
arrow

in

the

figure.

The

resistivity

measurements were carried out using a van der
Pauw method as used for LiAl [3]. Thisobservationisclosely

relatedtothethermodynamic properties of the structuraldefects, already observed as the anomalies inheat capacity [6] and nuclear-spin lattice
relaxation [5] at 233K near the criticalcomposition of the Li-deficient LiGa. It has beensuggested that these phenomena are related totheorder–disordertransformationofLivacancies in the compounds. The ordering of theFig. 1 Temperature-dependence of diffusion
coefficients (closed square) and electricalresistivity (open square) for LiIn with 48 at.% Li,
and that of diffusion coefficients (closed circle)
and electrical resistivity (open circle) for LiGa
with 44 at.% Li.

vacancies produces a sharp drop in the Li diffusion coefficients below the ordering temperature, since thevacancies are supposed to be the carriers of Li atom. The observed amount of change, more than two ordersof magnitude in the value of diffusion coefficients in the case of LiGa, is quite clear as compared to thoseobserved in the measurement of electrical resistivities where just a small change (at most 1/10) can be seenat the transformation temperature.
As shown in Fig. 1, the diffusion coefficients of Li in LiIn of 48 at.% Li follow Arrhenius behavior in boththe temperature regions above and below 207K at which temperature the sudden changes of Li diffusionand electrical resistivities would be induced by the order-disorder transformation of Li vacancies as same asin the case of LiGa. The first-time observation of Li diffusion related to the order-disorder transformationof Li vacancies in LiIn showed that the activation energy of Li diffusion below 207K is larger than thatabove 207K. The detail analyses for the order-disorder features of Li vacancies in LiIn are now in progresscompared with the case of LiGa.
References[1] S.C. Jeong, H. Sugai and M. Yahagi, BUTSURI, 64 (2009) 687-691 (in Japanese).
[2] J.C. Tarczon, et al., Mater. Sci. and Eng., A101 (1988) 99-108.
[3] H. Sugai, et al., Phys. Rev., B52 (1995) 4050-4059.
[4] K. Kuriyama, et al., Phys. Rev., B54 (1996) 6015-6018.
[5] K. Nakamura, et al., Faradsy Discuss., 134 (2007) 343-352.
[6] H. Hamanaka, et al., Solid State Ionics, 113-115 (1998) 69-72.

- 92 -

JAEA-Review 2010-056

6.4

Diffusion coefficient measurements on perovskite-type
lithium ion conductor

S. Takai1, S.C. Jeong2, I. Katayama2, H. Kawakami2, H. Ishiyama2, N. Imai2, Y. Hirayama2,
Y. Watanabe2, H. Miyatake2, M. Sataka3, H. Sugai3, S. Okayasu3 and T. Nakanoya3

More and more attention has been attracted on the materials for the energy devices, e.g. fuel cells, lithium
rechargeable batteries, or solar cells.

Lithium ion conductors have been studied for the application ofsolid electrolite of the lithium rechargeable batteries as well as the gas sensors.

Perovskite-type structured

La2/3-xLi3xTiO3 solid solutions (0 < x < 0.166) exhibit excellent lithium ion conduction and the compoisition
around x = 0.116 has been reported the highest lithium ion conductive oxide so far [1].

In this system, La

and Li ions occupy the A site of the perovskite-type structure accompanied by vacancy, while Ti ion occupy
the B site.

Lithium ion is supposed to migrate only when the adjacent A-site is vacant.

The

compositional dependence of lithium ion conductivity has been explained by the model that lithium ion
conductivity was depressed in the lower and higher x region due to the smaller numbers of charge carriers
and of vacancies, respectively.

On the other hand, in terms of the diffusion coefficients, the samples ofsmaller lithium content are simply preferred for the benefit of the jump probability of lithium ions.

We

have measured the tracer diffusion coefficient measurements on La2/3-xLi3xTiO3 system by means of neutron
radiography technique [2].

Stable 6Li tracer as the form of LiNO3 was introduced from the surfaces of

La2/3-xLi3xTiO3 sample blocks composed of 7Li and transmitted intensity of neutron were measured after
diffusion annealing. Based on the large difference of neutron absorption coefficients between 6Li and 7Li,
isotope concentration profiles can be obtained.

However, due to the resolution limit of imaging plate foroneutron, diffusion annealing above 200 C were necessary to accomplish the diffusion experiment within themachine time.

This implies that the diffusion coefficient cannot be directly measured around room

temperature by this method.
A new technique employing the short lived 8Li radiotracer (t1/2 = 0.84 s) has been recently developed [3].
The diffusion samples are irradiated by 8Li particles which break up into -particles in the sample through8

Be with -emission, and 8Li tracer concentration profiles are calculated from the time dependence of thedetected -particles during the 8Li beam-on/off cycles.
the calculated isotope concentration profiles.

The diffusion coefficients can be deduced from

Since  particle detection is sensitive to the depth in thesample, diffusion coefficients were supposed to be measured even for lower temperatures despite of short
lived-radiotracer.

In the present study, we applied this procedure to the diffusion coefficientmeasurements on the Perovskite-type lithium ion conductors below 200oC.
La2/3-xLi3xTiO3 (x = 0.067, 0.117 and 0.167) samples were prepared by the conventional solid state
reaction method.

The sintering temperatures were selected in the range 1310 – 1350oC depending on the1

Tottori University
High Energy Accelerator Research Organization (KEK)3Japan Atomic Energy Agency (JAEA)
2- 93 -

JAEA-Review 2010-056

composition. The sintered sample pellets with thediameter 10 was polished to achieve the mirror
To remove the diamondabrasive powder and residual strain, samples werethen annealed at 800oC.

As the “quenched sample”,

those of x = 0.117 were partly heat treated up to
1200oC followed by fast cooling using liquid N2.
8Liradiotracer,

provided

by

TRIAC

-yields / arb. units

finish on the surface.

o

100 C

2.5

(Tokai0Radioactive Ion Accelerator Complex at Tandem

2.0

periodically implanted to the sample with the fixed
time sequence, 1.67 s and 5.00 s for beam-on and off,The -particles came from the

4.0

6.0

Time, t / s

Accelerator Facility in JAEA) of 0.46 MeV u–1 wasrespectively.

2.0

Fig. 1Time spectra of the -particle yields forLa2/3-xLi3xTiO3 measured at 100oC. ○: x = 0.067, □:x = 0.117, ■: x = 0.117 (quenched), and △: x = 0.167.

samples were detected by SSD (Solid State Detector)
The timevariations of -intensity in the sequence werecollected

repeatedlytoaccumulate.

Themeasurements were carried out in the temperature
range between room temperature and 250oC.

-yields / arb. units

set in front of the sample surface.

x = 0.117

Figure 1 shows the time spectra of the -particle
yields measured at 100oC, which were normalized by
the intensity at the beam-off time.

profiles roughly resembled each other, they differed indetail as shown in the inset.

The time spectrum of x

= 0.117 was fitted based on the model assuming the
decay and diffusion of 8Li, which are also represented
in Fig. 2.

0

2.0

Although these

4.0

6.0

Time, t / s

Fig. 2Time spectrum of the -yields forLa2/3-xLi3xTiO3 (x = 0.117) measured at 100oC.
Rectangles: measured data as Fig. 1, red solid line:
calculated and bottom solid line: difference.

By fitting profile, diffusion coefficients were tentatively deduced as 2.3×10-9 cm2s-1, which is

close to the extrapolation of the high temperature diffusion data obtained by the previous neutron
radiography.
More precise analyses are now in progress, but it should be noted that the quenched sample seemed to havehigher diffusion coefficient.

Further analyses would help not only the understanding of diffusion

mechanism but also the designing of electrolyte devices.
References[1] Y. Inaguma et al., Solid State Commun., 86 (1993) 689-693.
[2] S. Takai et al., Solid State Ionics, 176 (2005) 2227-2233.
[3] S.C. Jeong et al., Nucl. Instrum. Methods Phys. Res., B230 (2005) 596-600.

- 94 -

JAEA-Review 2010-056

6.5

High-energy ion impact effects on atomic structure
and optical property of In-doped ZnO films
N. Matsunami1, M. Sataka2, S. Okayasu2 and H. Kakiuchida3

Zinc oxide (ZnO) doped with trivalent elements is known as n-type transparent semiconductor [1, 2]. We
have studied atomic-structure and optical-property modifications of Al-doped ZnO (AZO) films underhigh-energy ion impact [3]. In this study, we have investigated modifications of In-doped ZnO (IZO) by
high- and low-energy ion impact [4] to compare with those of AZO and of IZO by low-energy ion impact.
IZO films were prepared on SiO2-glass substrates (~0.5x1x0.05 cm3) at 500 ºC by using a RF-magnetron
sputtering deposition (off-axis) method [4]. The X-ray diffraction (XRD) shows that the films are polycrystalline with c-axis orientation of hexagonal wurtzite structure (Fig. 1). The substrate temperature was
optimized to maximize the XRD intensity. The lattice parameter averaged over unirradiated 30 samples was
obtained to be 0.5249 nm (sample variation of 0.4 %) and is larger by 0.8 % than 0.52069 nm in the literature[2]. Full-width at half-maximum (FWHM) of the XRD rocking curve of unirradiated films is 8±2.5 º (Fig. 1
inset). Rutherford backscattering spectrometry (RBS) using 1.8 MeV He+ ions was employed to evaluate thecomposition and thickness. In RBS analysis, Zn density is taken as 4.2x1022 cm-3 and the contribution of In
to the stopping power [5] is discarded. The composition of the unirradiated films is very close to
stoichiometric within RBS accuracy of 10%, i.e., In1-xZnxO with x≃0.94 (In/Zn≃6%). The film thickness is
100 to 150 nm. The films were irradiated with 100 MeV 136Xe+11 and 100 keV Ne+ ions at room temperature.
It is found that the composition remains unchanged under the ion impact.
Figs. 1 shows XRD patterns of unirradiated IZO film and the film irradiated with 100 MeV Xe ions at
2.5x1012 cm-2. The main diffraction peak is ZnO (002) at ~34 º and peaks other than ZnO such as In andIn2O3 were not observed. XRD intensity monotonically decreases with the ion fluence, reduction of the XRD
intensity by ~30 % was observed at 3x1013 cm-2. Interestingly, FWHM of the rocking curve decreases by 7 %(slightly larger than the estimated error of 5 %) after Xe ion impact at 2.5x1012 cm-2 (Fig. 1 inset). This could
be due to grain-orientation alignment as observed for ZnO (a-axis orientation) on MgO [6], SiO2 on Si(100)[7] and AlN on R-cut-Al2O3 [8]. FWHM increases for further ion irradiation. It also appears that the lattice
parameter monotonically decreases by ion impact, and the lattice compaction of 1.7 % is observed at 1x1014
cm-2 of 100 MeV Xe. For, 100 keV Ne ion impact at 1x1017 cm-2, a slight increase of the XRD intensity,
reduction of rocking-curve FWHM by 12 % and lattice compaction of 0.8 % were observed. In view of XRD,
atomic structure modification by high- and low-energy ion impact is insignificant, except for the latticecompaction.
Optical absorption spectrum of IZO film is shown in Fig. 2. The optical absorbance (OA, absorbance isdefined as log10(Io/I), Io and I being incident and transmitted photon intensity) of unirradiated films (morethan ten samples with thickness of 60 to 400 nm) at the photon energy of 4 eV (310 nm) increases linearlywith the film thickness and OA divided by the film thickness (L), called absorbance coefficient herein isdetermined to be 7.5x10-3 nm-1 with an estimated error of 10 % (or the absorption coefficient, α of 1.73x105
cm-1, I= Io exp(-αL)) and is comparable with 6.67x10-3 nm-1 (α=1.54x105 cm-1) for AZO [3]. The refractive
index (n) of unirradiated film is approximately given by: n=1.93+0.00526/λ2+0.00755/λ4 with the sample
variation of a few %, λ being the wavelength (μm), and n(IZO) is larger by 9-4 % than n(AZO) for λ=0.4-1.7
μm. Ion irradiation effects on the refractive index are under way.
_____________________________________________________________________
1
Division of Energy Science, EcoTopia Science Institute, Nagoya University
2
Japan Atomic Energy Agency (JAEA)
3
National Institute of Advanced Industrial Science and Technology (AIST)- 95 -

JAEA-Review 2010-056

Modifications of absorption spectra, bandgap and absorption-edge slope by 100 MeV Xe ions are seen in Fig.
2. The absorbance increases by several % up to 1013 cm-2 and decreases by ~4 % at 1014 cm-2. The
absorption-edge slope is obtained to be the slope in the linear part of absorbance vs photon energy (Fig. 2)
and divided by the absorbance of the unirradiated film at 4 eV for normalization of the film thickness (anestimated error of 5%). The absorption-edge slope monotonically decreases from 1.7 eV-1 (smaller than 3.3
eV-1 of unirradiated AZO) to 1.2 eV-1 for 100 MeV Xe at 1x1014 cm-2, similarly to AZO under 100 MeV Xe
ion irradiation. The bandgap Eg is determined by using a relation for direct bandgap: (absorbance*E)2 is
proportional to (E – Eg), E being the photon energy. The bandgap of unirradiated IZO films is obtained to be
3.2 eV (±2%) and this is somewhat smaller than that of AZO, 3.37 eV [3]. The bandgap increases by 0.25 eV
for 100 MeV Xe ion at 1014 cm-2 (Fig. 2, inset).
For 100 keV Ne, the absorbance coefficient increases from 8.1x10-3 nm-1 with the Ne ion fluence and reaches
saturation of 9.7x10-3 nm-1 (~20 % increase) at ~1x1017 cm-2, the absorption-edge slope decreases to 0.73
eV-1 at 1x1017 cm-2 and Eg increases by ~0.045 eV comparable with the accuracy of 0.06 eV at 1x1016 cm-2
and for further irradiation Eg decreases by 0.11 eV at 1x1017 cm-2. The decrease of the bandgap by the 100
keV Ne contrasts with the increase in the bandgap of IZO and AZO under 100 MeV Xe ion impact [3]. As
mentioned earlier, the XRD intensity shows insignificant change. A speculation is that the optical property ismore sensitive to ion impact than XRD and disorder induced by ion irradiation reflects in the opticalabsorption.
2

3

100 MeV Xe
12-2
2.5x10 cm

1

0

12

16

20

100 MeV Xe
12unirrad.

1-2

100 MeV Xe, 2.5x10 cm

0

32

34

36

2 (DEG.)

38

40

0

42

Fig. 1 XRD patterns and rocking curves (inset)
before and after 100 MeV Xe+11 ion impact at
2.5x1012 cm-2. The peak at ~34 º corresponds toZnO (002) diffraction peak (i.e., c-axis orientation),~31 º and 32.6 º (In2O3), and 33 º (In) were notobserved. In the inset, horizontal lines indicate
the full-width at half-maximum (8.45 and 7.83 ºbefore and after the ion impact).

-230x10 cm

24

 (DEG.)
12

2

2

3

2

1

unirrad.

(ABSORBANCE*E)

unirrad.

ABSORBANCEXRD INTENSITY (a. u.)

XRD INTENSITY (a. u.)

2

80
60
40
unirrad.
20
0
3

100 MeV Xe
30x10

4
5
PHOTON ENERGY (eV)

cm

-2

6

Fig. 2 Optical absorption spectra of unirradiated
IZO film and the film irradiated with 100 MeV
Xe+11 at 3x1013 cm-2. Dotted lines indicate theabsorption-edge slope. The inset shows thesquare of absorbance times photon energy (E)vs E, illustrating the band gap (Eg) indicated byvertical lines (Eg =3.239 and 3.546 eV before
and after the ion impact).

References[1] T. Minami et al., Jpn. J. Apl. Phys., 24 (1985) L781.
[2] S. J. Pearton et al., Prog. Mater. Sci., 50 (2005) 293.
[3] O. Fukuoka etal., Nucl. Instrum. Methods Phys. Res., B250 (2006) 295.
[4] N. Matsunami et al., Nucl. Instrum. Methods Phys. Res., B, 2010, in print.
[5] J.F. Ziegler, J.P. Biersack and U. Littmark, “The Stopping and Range of Ions in Solids”,
Pergamon Press, New York (1985).
[6] N. Matsunami et al., Nucl. Instrum. Methods Phys. Res., B245 (2006) 231.
[8] N. Matsunami et al., Nucl. Instrum. Methods Phys. Res., B257 (2007) 433.

- 96 -

12

3.5
4
4.5
PHOTON ENERGY (eV)JAEA-Review 2010-056

6.6

Electrical property modifications of In-doped ZnO films
by high-energy ion impact
N. Matsunami1, M. Sataka2, S. Okayasu2 and H. Sugai2

We have studied electrical property modifications of Al-doped ZnO (AZO) films, known as n-typetransparent semiconductors [1], under high-energy ion impact and found drastic increase in the electricalconductivity [2]. The conductivity increase is ascribed to the carrier density increase due to replacement of
Zn on the lattice site by Al on site other than lattice site (called ion-induced dopant-replacement). It is ofinterest whether ion-induced dopant-replacement takes place for trivalent element other than Al or not. In
this study, we have investigated electrical property modifications of In-doped ZnO (IZO) by high- andlow-energy ion impact [3] to compare with those of AZO and of IZO by low-energy ion impact.
Preparation of IZO films on SiO2-glass substrates, characterization of the films and modifications ofatomic-structure and optical-property by high-energy ions are described [3] (Tandem Report 2009, 7.2).
The composition of the unirradiated film is very close to stoichiometric within RBS accuracy of 10%, andIn/Zn≈6%. The films were irradiated with 100 MeV 136Xe+11 and 100 keV Ne+ ions at room temperature. It
is found that the composition remains unchanged under the ion impact. DC resistivity was measured with
four-terminal method in situ in the irradiation chamber and Hall-effect was measured after take the sample
outside from the chamber.
The electrical conductivity of unirradiated IZO films appears to scatter by two orders of magnitude (0.1 to 10
Scm-1) depending on samples (Fig. 1). The possibilities for the scatter are: Firstly, a small but certain fractionof In has already occupied Zn site and secondary, impurities especially hydrogen exist in the films and theircontent varies with sample. In spite of large scatter of the initial conductivity, the very similar maximum
conductivity of 400 and 200 Scm-1, comparable with the conductivity in [1], has been reached after impact of
100 MeV Xe+11 and 100 keV Ne+ ions, respectively (Fig. 1 and Table 1). Here, the thickness of two films
used for 100 keV Ne+ impact is ~0.18 μm (larger than the projected range of 0.12 μm [4]) and the effective
depth is taken to be the projected range for evaluating the conductivity and carrier density. The main sourceof the conductivity increase (three to four orders of magnitudes) is the increase of the carrier density by~4x104 from ~1017 to 1021 cm-3 (Fig. 2 and Table 1), which is ascribed to In-dopant replacement induced byion impact. No simple relation is found between the conductivity and optical property modifications. The
beam current density is ~3 nA cm-2 and 1-3 μAcm-2 for 100 MeV Xe and 100 keV Ne ions. The temperaturerise during the ion impact is estimated to be ~40 ºC [5], which is insignificant. It appears that temperature (T)dependence of the conductivity from 180 to 300 K is proportional to exp(-Ea/kT), i.e., semiconductor
behavior for IZO both unirradiated and irradiated with 100 keV Ne at 1x1017 cm-2. The activation energy (Ea)is obtained to be 0.09 and 0.024 eV, respectively. Here k is the Boltzmann constant. T-dependence of the
conductivity is under way for the films irradiated with 100 MeV Xe ions.
Displacement per atom (dpa) due to the elastic collisions is estimated to be 13 for 100 keV Ne at 5x1016 cm-2
(Table 1) [6]. From similarity of the conductivity enhancement in IZO and AZO by 100 MeV Xe ion, it
appears that the electronic excitation plays dominant role in high-energy ion impact. The electronic
sputtering yield of ZnO by 100 MeV Xe is estimated to be 8.0 [7]. The equivalent dpa, proportional to theratio of the electronic over elastic sputtering yields, is obtained to be 0.8 for 100 MeV Xe at 3.8x1014 cm-2.
Thus, the efficiency of dopant-replacement by electronic excitation is higher than the elastic collisions. Inview of ionic radius, dopant-replacement looks easy, though the ion-induced mechanism has not been
established yet. Here, ionic radius in 4 coordinates of Zn2+, In3+ and Al3+ is 0.074, 0.076 and 0.053 nm [8].
_____________________________________________________________________
1
Division of Energy Science, EcoTopia Science Institute, Nagoya University
2
Japan Atomic Energy Agency (JAEA)- 97 -

JAEA-Review 2010-056

3+11

100 MeV Xe

100

+11

100 MeV Xe

IZX5a

1

10

IZX5b
(156.5 nm)

0

IZX5a
(147.7 nm)

10

10

2

MOBILITY (cm /Vs)

(144 nm)MOBILITY

1
unir.

10

IZC3a

2

19

10

unir.

-1

CONDUCTIVITY (Scm )-3

CARRIER DENSITY(10 cm )10

CARRIER DENSITY

0.1

-1

0.01

0.1

1

10

100 MeV Xe FLUENCE(10

100
12

0.01
0.01

1000
-2

cm )

Fig. 1 Conductivity of IZO films vs 100 MeV
Xe+11 ion fluence for three samples with thickness
given in the parenthesis. Open symbols (〇, ◇, □)indicate the conductivity of unirradiated films.
Open triangles (△) mean conductivity decreaseduring the ion beam break for Hall measurements
in air (sample-IZX5a).

0.1

1
10
100
12
-2
100 MeV Xe FLUENCE (10 cm )1000

Fig. 2 Carrier density (●) and mobility(▲) of IZO films vs 100 MeV Xe+11 ion
fluence. Open symbols (〇, △) indicate
carrier density and mobility ofunirradiated film.

Table 1 Projected range (Rp), electronic (Se) and nuclear (Sn) stopping powers (keV/nm) near surface of ZnO
for 100 MeV 136Xe+11 and 100 keV Ne+ ion irradiation, Snd= Sn-ionization by recoils, maximum conductivity(σ), fluence (F) at which σ takes its maximum, carrier density (N) and mobility (μ). Values in parentheses in
the 2nd row are Se, Sn and Snd averaged over Rp for 100 keV Ne+. dpa for 100 keV Ne and equivalent dpa for
100 MeV Xe are also given (see text). The values in bracket below N are the enhancement factor of N by ion
irradiation. Rp, Se, Sn and Snd were calculated using TRIM97 [4].
Ion

Rp
(μm)

Se

Sn
Snd
(keV/nm)dpa

σ(Scm-1)

F(cm-2)

N(cm-3)

100 MeV Xe

9.4

21.1

0.195

0.8

423

3.8x1014

100 keV Ne

0.12

0.265
(0.253)0.242(0.368)200

5x10169.6x1020[3.3 x104]
3.5x1021[5x104]0.212(0.247)13

References[1] T. Minami et al., Jpn. J. Appl. Phys.. 24 (1985) L781.
[2] H. Sugai et al., Nucl. Instrum. Methods Phys. Res., B250 (2006) 291.
[3] N. Matsunami et al., Nucl. Instrum. Methods Phys. Res., B, 2010, in print.
[4] J.F. Ziegler, J.P. Biersack and U. Littmark, “The Stopping and Range of Ions in Solids”,
Pergamon Press, New York (1985).
[5] N. Matsunami, T. Yajima, H. Iwahara, Nucl. Instrum. Methods. Phys. Res.,B65(1992)278.
[6] N. Matsunami et al., Surf. Coatings Technol., 196(2005)50.
[7] N. Matsunami et al., Nucl. Instrum. Methods Phys. Res., B209(2003)288.
[8] M. W. Barsoum, “Fundamentals of Ceramics”, McGraw-Hill, 1997.

- 98 -

μ(cm2/Vs)
2.7
0.32

JAEA-Review 2010-056

CHAPTER 7
Radiation Effects in Materials

7.1

Ion charge dependence on diameter of ion tracks in UO2

7.2

Microstructure observations and distribution of chemical compositions ofmetal precipitates in Zircaloy-2 under irradiation with 210 MeV Xe ions7.3

Electrical conductivity change in CeO2 irradiated with high-energy heavy ions

7.4

Effects of energetic heavy ion irradiation on the crystal structure
in Gd2O3-doped CeO2

7.5

Effect of high temperature annealing on ferromagnetism
induced by swift heavy ion irradiation in FeRh alloy

7.6

Shape and property control of Zn and ZnO nanoparticles by swift heavy ions

7.7

Elongation of Au nanoparticle in SiO2 matrix irradiated with swift heavy ions

7.8

Radiation damage test for Virtex-5 FPGA

7.9

Transport properties of (-FeSi2) thin films

7.10

Formation of metal microstructure induced by ion irradiation in Ag-zeolite

7.11 Angular dependences of flux pinning properties
in YBCO thin films with crossed columnar defects
7.12

Swift ion implantation for fabrication of optical waveguides

7.13

Dynamic nuclear polarization study of meso-scale spatial distribution offree radicals generated by carbon and electron beams

7.14

Track characterization of oxygen ions in solid state track detector- 99 -

This is a blank page.

JAEA-Review 2010-056

7.1

Ion charge dependence on diameter of ion tracks in UO2
T. Sonoda 1 , T. Sawabe1, N. Ishikawa 2 and M. Sataka2

In order to understand the formation and growth mechanism of a crystallographic exchange in high burnup
fuels such as “rim structure [1]”, clarification of radiation effects under nuclear fissions such as theelectronic excitation effects, accumulation of radiation damage and fission products (FPs) should be needed.
In this study, high density electronic excitation effects on the accumulation process of radiation damages in
LWR fuels [2-4] have been clarified. The diameter of ion tracks of high energy ion irradiation to the thin
foil samples was investigated. In previous study, though, the charge of irradiated ion may not be
equilibrium charge in materials. Therefore, in order to understand the “real” diameter of ion tracks in UO2
under nuclear fission, the effect of ion charge on the diameter of ion tracks should be clarified. In this study,
several charge and energy ions such as 100 MeV Xe25+, 100 MeV Zr10+, 210 MeV Xe16+, 210 MeV Xe 29+,150 MeV Xe27+, 150 MeV Au27+, 310 MeV Au27+ are irradiated to the non-irradiated thin UO2 samples thatare fabricated by FIB (Focused Ion Beam) method. Microstructure evolutions in the irradiated samples areobserved in a FE-SEM (JSM-6340F) and a FE-TEM (HF-3000) at CRIEPI. This work was partly supported
by MEXT KAKENHI (21360474).
Figure 1 (a) to (g) indicate the typical bright field images of ion tracks in UO2 irradiated with (a) 100 MeV
Xe25+, (b) 100 MeV Zr10+, (c) 210 MeV Xe16+, (d) 210 MeV Xe 29+, (e) 150 MeV Xe27+, (f) 150 MeV Au27+,and (g) 310 MeV Au27+ions at room temperature. The elliptical circle images in these pictures correspond tothe cross-section images of ion tracks, and the diameter is defined as the length of minor axis of the circles.
The mean diameter of ion tracks is (a) 2.0 ±0.1 nm, (b) 1.8 ±0.1 nm, (c) 4.9 ±0.1 nm, (d) 4.4 ±0.1
nm, (e) 3.7 ±0.1 nm, (f) 3.6 ±0.1 nm, and (g) 5.0 ±0.1 nm, respectively.
Figure 2 indicates the mean diameter of ion tracks in UO2 and CeO2 [4] as a function of irradiation energy.
The diameter of ion tracks in UO2 become bigger as increasing irradiation energy, and the size tends tosaturate over 210 MeV. The tendency of the curve is similar of that of CeO2, though, the diameter of ion
tracks in UO2 is much smaller than that of CeO2. These results indicate that the sensitivity of high density
electronic excitation of UO2 is much less than that of CeO2. Moreover, the comparison between (c) and (d)indicates that the diameter of ion tracks is almost same in case of different ion charge. This result suggeststhat the differences of ion charges are not so effective on the diameter of ion tracks. Figure 3 shows thesquare of mean diameter of ion tracks in UO2 and CeO2 [4] as a function of electronic stopping power (Se).
This figure indicates that the gradient of the square of diameter from 100 MeV Xe to 210 MeV Xe is tend
to be same and it suggests that the square of diameter of ion tracks tend to be proportional to electronic
stopping power (Se). In order to understand the relationship among Se, diameter of tracks and irradiation
conditions, additional ion irradiation examination should be needed.

1
2

Central Research Institute of Electric Power Industry (CRIEPI)Japan Atomic Energy Agency (JAEA)- 101 -

JAEA-Review 2010-056

(a)

(b)

(e)

(c)

(f)

(d)

(g)

Fig. 1 TEM image of UO2 irradiated with (a) 100 MeV Xe+25, (b) 100 MeV Zr+10, (c) 210 MeV Xe+16, (d)210 MeV Xe +29, (e) 150 MeV Xe+27, (f) 150 MeV Au+27, and (g) 310 MeV Au27+ions to a fluence of 5 x
1011 ions/cm2 at room temperature.
Xe
Zr CeO2I
Xe
Au UO2
Zr

Fig. 2 Mean diameter of ion tracks in
UO2 and CeO2 at room temperature as afunction of irradiation energy (MeV).

Fig. 3 The square of the mean diameter of ion
tracks in UO2 and CeO2 at room temperature asa function of electronic stopping power (Se).

References[1] J.O. Barner et al., HBEP-61, 1990, Battelle Pacific Northwest Laboratories.
[2] T. Sonoda et al., Nucl. Instrum. Methods Phys. Res., B191 (2002) 622-628.
[3] T. Sonoda et al., Nucl. Instrum. Methods Phys. Res., B250 (2006) 254-258.
[4] T. Sonoda et al., Nucl. Instrum. Methods Phys. Res., B266 (2008) 2882-2886.

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JAEA-Review 2010-056

7.2

Microstructure observations and distribution of chemical compositionsof metal precipitates in Zircaloy-2 irradiated with 210 MeV Xe ionsT. Sonoda 1 , T. Sawabe1, N. Ishikawa 2 and M. Sataka2

In order to progress high burnup extension of light water reactor (LWR) fuels, the improvement ofanti-corrosion and hydrogen resistance of nuclear fuel claddings (Zirconium alloy; Zircaloy-2 for boilingwater reactor) is indispensable. In previous researches, it becomes clear that the degradation ofanti-corrosion and hydrogen resistance is concerned with the composition and size of metal precipitates inzirconium alloy, and the precipitates are deformed under irradiation with high energy neutron in a reactor[1]. In order to clarify the mechanism of corrosion and hydrogen pickup in Zircaloy and the correlation
between the degradation of fuel cladding and the deformation of metal precipitates in claddings,
microstructure observations and ion irradiation examinations have been done. Especially, there are no
information about the deformation of metal precipitates in cladding materials under high energy ion
irradiation condition such as the bonding layer of cladding inner surface and fuel pellet. In this report,
microstructure and atom distribution of alloy elements and impurity (Fe, Ni, Cr, and Si) in Zircaloy-2 underirradiation with 210 MeV Xe ions at room temperature have been clarified by means of a transmission
electron microscope (JEM-2100 with EDS system) at CRIEPI. Ion irradiation examinations have been done
at JAEA-Tandem accelerator facility.
Figure 1 (a) to (c) indicates the typical microstructure of Zircaloy-2 irradiated with 210 MeV Xe ions to afluence of 5 x 1015 ions/cm2 at room temperature, and (a)’ to (c)’ indicates the EDS spectrum at the positionof “002”, “020” and “013” in (a) to (c), respectively. The black circle contrasts correspond with the metal
precipitates in Zircaloy-2, and (a)’ to (c)’ shows that the precipitate in (a) and (b) is a metal precipitate of(Fe, Cr) base and (c) is of (Fe, Ni) base. The depth position of (a) from the irradiation surface is over 5 m,and (b) and (c) is less than 2 m, respectively. The size of precipitates are almost same as that of
non-irradiation sample whose size is around 50 – 300 nm. Table 1 indicates the Fe, Ni and Cr atom
concentration (at%) and the ratio of Fe/Cr and Fe/Ni of metal precipitate in (a) to (c). In case of (a) that themetal precipitate of (Fe, Cr) base at the deeper position from irradiation surface, the ratio of Fe/Cr is 0.85
and the ratio is not so changed. Though, in case of the metal precipitate of (Fe, Cr) base at shallow position
from the surface as shown in (b) , the ratio of Fe/Cr is 0.49 and it becomes clear that Fe atom tend to
dissolve from precipitate to the matrix priory. In case of precipitate of (Fe, Ni) base at shallow position
from the surface as shown (c), the ratio of Fe/Ni is around 1.25 and the concentration of Fe and Ni isaround 14.4 and 11.5 at%, respectively. The ratio and the concentration of Fe and Ni are almost same as
non-irradiated materials. These results suggest that the irradiation accelerate the dissolution of Fe ions inmatrix priory in case of (Fe, Cr) base precipitates, and not accelerate the dissolution of Fe ions in case of(Fe, Ni) base precipitates. These tendencies of Fe ion are almost same as that of high burnup fuel cladding[1]. In order to clarify the irradiation effects, such as electronic excitation, on the degradation of metal
1
2

Central Research Institute of Electric Power Industry (CRIEPI)Japan Atomic Energy Agency (JAEA)- 103 -

JAEA-Review 2010-056

precipitates, further irradiation examination will be treated in near future.

(b)

(c)

(a)’

(b)’

(c)’
(counts)(counts)(counts)

(a)

(keV)

(keV)

(keV)

Fig.1 Typical microstructure of Zircaloy-2 irradiated with 210 MeV Xe ions to a fluence of 5 x
1015 ions/cm2 at room temperature, and (a)’ to (c)’ indicates the EDS spectrum at the position of“002”, “020” and “013” in (a) to (c), respectively. The precipitate of (a) and (b) is the metal
precipitates of (Fe, Cr) base and (c) is the precipitate of (Fe, Ni) base.

Table 1. Fe, Ni and Cr atom concentration (at%) and the ratio of Fe/Cr andFe/Ni of metal precipitate in (a) (b) and (c).

position

Fe
(at%)

Cr
(at%)

Ni
(at%)

Zr

Fe/Cr

Fe/Ni

Type

002

17.09

20.06

0

balance

0.85--

Zr(Fe, Cr)2

020

6.9

14.08

0

balance

0.49--

Zr(Fe, Cr)2

013

14.38

0.21

11.49

balance--

1.25

Zr2(Fe, Ni)

References[1] Y. Etoh, et al., J. Nucl. Mater., 200 (1993) 59.

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JAEA-Review 2010-056

7.3

Electrical conductivity change in CeO2 irradiated withhigh-energy heavy ions
N. Ishikawa 1 and K. Takegahara1,2

Radiation damage in nuclear fuel can be classified into various types in term of its defect structure, such as1) point-like defects created by relatively low energy particle irradiation, 2) continuous damage region(ion-track) created by high energy particle irradiation, and 3) strain fields created by accumulation offission gas. In this study, in order to simulate the second process, i.e. radiation damage process by highenergy fission fragments in nuclear fuel, oxide ceramic material (CeO2) with same fluorite crystallographic
structure as UO2 is irradiated with high energy particles using tandem accelerator at JAEA-Tokai. The
characterization of radiation damage is done by in-situ electrical resistivity measurement.
Thin films of CeO2 were prepared on single crystal sapphire substrates by sputtering methods. The film
thickness was about 300 nm. The films were irradiated at room temperature with 120MeV Xe from thetandem accelerator at JAEA-Tokai. The objective of the irradiation with 120MeV Xe ions is to simulate
radiation damage behavior due to high energy fission fragments. Current is measured in-situ when voltage
is applied in the range from -100V to 100V. The current-voltage relation is measured by two-probe method
using Keithley 6517 (Electrometer/High Resistance System). The electrodes are prepared by depositing
gold on the sample using sputtering technique. Before irradiation the electrical conductivity was around10-6 ohm-1・m-1.
Figure 1 shows the current-voltage relation of CeO2 before and after the irradiations. It is found that thecurrent-voltage relation is linear both for unirradiated and irradiated samples, indicating that electricalconductivity can be defined as constant value irrespective of the applied voltage value.

Another importantresult from this figure is that the slope of the I-V curve increases monotonically as a function of fluence,indicating that the electrical conductivity increases as fluence increases.

In Fig.2 we find that theelectrical conductivity increases three orders of magnitude at high fluence of 1013 ions/cm2. In the fluence
range from 1012 ions/cm2 to 1012 ions/cm2, where the occupancy of ion-tracks in the sample is expected tovary from 30% to 98% if track diameter of 7nm is assumed [1], prominent electrical conductivity increase
is observed.

On the other hand, in the high fluence range of around 1014 ions/cm2 where multiple

overlapping of ion-tracks is dominant, increase in electrical conductivity tends to saturates, suggesting thatthe multiple overlapping of ion-tracks does not efficiently lead to increase in electrical conductivity.
References[1] T. Sonoda et al., Nucl. Instrum. Methods Phys. Res., B250 (2006) 254.

1
2

Japan Atomic Energy Agency (JAEA)
Ibaraki University- 105 -

JAEA-Review 2010-056

Current [nA]

200

0
14

2

13

2

12

2

10 ions/cm
10 ions/cm
10 ions/cm
unirrad.

−200
−100

0

100

Voltage [V]

10

−2

−1

−1

Electrical Conductivity(Ω m )Fig. 1 Current-Voltage characteristics observed for a CeO2 thin film before andafter the irradiation with 120MeV Xe ions. The solid lines are the results of linear
fitting of the data in the voltage range from -100V to 100V.

10

−4

−6

10 10
10

10

12

10
2

14

Fluence (ions/cm )Fig. 2 Fluence dependence of electrical conductivity for a CeO2 thin film
irradiated with 120MeV Xe ions. The solid circles are the values measured basedon linear fitting of current-voltage relations. The open circles are the values
measured based on the current value at applied voltage of 100V.

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JAEA-Review 2010-056

7.4

Effects of energetic heavy ion irradiation on the crystal structure
in Gd2O3-doped CeO2
Y.Tahara1, B.Zhu1, S.Kosugi1, N.Ishikawa2, Y.Okamoto2,
Y. Baba2, N. Hirao2, F. Hori1, T.Matsui1 and A.Iwase1

In present light-water nuclear power plants, it is useful to dope some elements called burnable poisons,which have a high neutron absorption cross section, into enriched fission fuels (UO2) in order to control the
initial reactivity of UO2 fuels. Actually, gadolinium trioxide (Gd2O3) has already been doped into UO2 as aburnable poison. During the operation of light-water power reactors, UO2 fuels are exposed to irradiation
with high energy fission products which have energies around 100MeV. Therefore, it is important to study
the effects of high energy fission products on UO2 fuels doped with Gd2O3.
For previous studies in irradiation effects on nuclear fuels[1,2], cerium dioxide (CeO2) has been used so far
as a simulation material for UO2 because it has the same fluorite structure as that of UO2 and has the similar
properties such as lattice constant and thermal conductivity to those of UO2. In this study, therefore, CeO2
pellets doped with Gd2O3 were irradiated with 200MeV Xe14+ ions using a tandem accelerator at
JAEA-Tokai to simulate the irradiation effects of high energy fission products on UO2 doped with Gd2O3.
The X-ray diffraction (XRD) method and the extended X-ray absorption fine structure (EXAFS)
measurement were used to estimate the effects of the Gd-doping and the irradiation.
Figure.1 shows the change in XRD spectra around (331) peaks of pure and 10mol% Gd2O3 doped CeO2 forvarious ion-fluences. The peak is sifted to higher angle for unirradiated samples by Gd2O3 doping, whichmeans that the lattice constant decreases by doping. On the other hand, the peaks are sifted to lower angle
by the irradiation, which means that the lattice constant increases by the irradiation and it increases withincreasing the ion ion-fluences. The figure shows that the effect of the irradiation on lattice constantbecomes more remarkable by Gd2O3 doping.
Figure.2 shows the change in the Fourier transformations of Gd L3-edge EXAFS spectra by doping andirradiation. When paying attention to the effects of Gd-doping, the intensity of the first and second
neighboring peaks decrease with increasing the amount of Gd-doping. It means that the structure aroundGd atoms is disordered locally by Gd2O3doping. In addition, as can be seen in Fig.3, the intensity of thepeaks decreases also by the irradiation. It is found that the irradiation induces a local disordering around Gd
atoms. Detailed analysis for EXAFS FT spectra is now in progress.

1
2

Osaka Prefecture University
Japan Atomic Energy Agency (JAEA)- 107 -

JAEA-Review 2010-056

Gd2O3 10mol% CeO2
1×1013/cm2

Intensity

1×1012/cm2
unirradiation

Pure CeO2

1×1013/cm2
1×1012/cm2
unirradiation

75.5

76

76.5

77

77.5

78

2θ

Fig. 1 XRD spectra around (331) of undoped CeO2 and those doped with 10mol%
Gd2O3 for various ion-fluences.

0.06

0.06
1mol unirrad

5mol unirrad

5mol unirrad

0.05

|FT|

|FT|

5mol 2E13

0.04

0.04
0.03

0.03

0.02

0.02

0.01

0.01

0

5mol 1E13

0.05

10mol unirrad

0

1

2

3

4

5

0

0

1

2

3

4

5

R[Ang]

R[Ang}

Fig. 2 Dependence of FT spectrum on theFig. 3 Dependence of FT spectrum on

amount

of

Gd2O3

for

unirradiatedion-fluence for CeO2 doped with 5 mol%
Gd2O3.

specimens.
References[1] M. Kinoshita et al., Nucl. Instrum. Methods , Phys. Res. B267 (2009) 960.
[2] H.Ohno et al., Nucl. Instrum. Methods Phys. Res., B266 (2008) 30.

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JAEA-Review 2010-056

7.5

Effect of high temperature annealing on ferromagnetism
induced by swift heavy ion irradiation in FeRh alloy
S. Kosugi 1 , N. Fujita1, N. Ishikawa2, F. Hori1, T. Matsui1 and A. Iwase1

In the previous studies, we have found that energetic ion irradiation induces a ferromagnetic state in Fe-Rh
alloys at low temperatures and this phenomenon is dominated by the energy deposition through elastic
collisions [1, 2]. As the effect remains unchanged at room temperature for a long time, the disordering ofatomic arrangements or lattice defects induced by the irradiation causes the ferromagnetism at low
temperatures. In this report, we discuss the relationship between the irradiation-induced ferromagnetism in
Fe-50at.%Rh alloy and the thermal stability of atomic disordering or lattice defects.
Specimens of Fe-50at.%Rh with the dimension of 5x5x0.2 mm3 were irradiated at room temperature with
200MeV Au ions by using a tandem accelerator at JAEA-Tokai. After the irradiations, the samples wereisochronally annealed up to 773K. Isochronal annals were for 60 minute periods at temperature interval of
100K. Effects of thermal annealing on magnetization were measured by using the superconducting
quantum interference device (SQUID). The scanning range of the applied magnetic field was from -6000 to
6000Oe and the measurement temperature was 20K.
Figures.1 and 2 shows the magnetic moment-magnetic filed curves for FeRh specimens annealed with 200
MeV Au ions irradiation. For the ion-fluence of 1x1013/cm2, the value of the saturated magnetization,<Ms>, continues to decrease until 773K. For the ion-fluence of 5x1013/cm2, the value of <Ms>, shows the
maximum after the annealing at 573K and the value of <Ms> decreases rapidly with increasing annealing
temperature. In Fig.3, the values of <Ms> are plotted against the annealing temperature. The values of<Ms> can be well correlated with the annealing temperature. The present result indicates that theirradiation-induced ferromagnetism of FeRh alloy is strongly related to the thermal stability ofirradiation-introduced lattice defects.

Magnetization [emu/g]

150
100
50

Fig. 1 Irradiation induced magnetic

0

moment at 20K as a function of appliedmagnetic field for Fe-50at.%Rh irradiated

-50
-100
-150
-6000 -4000 -2000

with 200MeV Au to the ion-fluence ofunannealed
373K
473K
573K
673K
773K

0

1x1013/cm2.

2000 4000 6000

Magnetic field [Oe]12Osaka Prefecture University
Japan Atomic Energy Agency (JAEA)- 109 -

JAEA-Review 2010-056

Magnetization [emu/g]

150
100
50
0
-50
unannealed
373K
473K
573K
673K
773K

-100
-150
-6000 -4000 -2000

02000 4000 6000

Magnetic field [Oe]Fig. 2 Irradiation induced magnetic moment at 20K as a function of applied magnetic
field for Fe-50at.%Rh irradiated with 200MeV Au to the ion-fluence of 5x1013/cm2.

100
1x1013/cm2
5x1013/cm2<Ms> [emu/g]

80
60
40
20
0
273

373

473

573

673

773

Temperature [K]Fig. 3 Average values of saturation magnetization, <Ms>, for the region
expect around the ion range, as a annealing temperaturte.

References[1] S. Kosugi et al., Nucl. Instrum. Methods Phys. Res., B267 (2009) 1612-1615.
[2] A. Iwase et al., Nucl. Instrum. Methods Phys. Res., B256 (2007) 429-433.

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JAEA-Review 2010-056

7.6 Shape and property control of Zn and ZnO nanoparticles
by swift heavy ions
H. Amekura 1 , N. Ishikawa2, K. Mitsuishi1, Y. Nakayama1 and N. Kishimoto1

When metal nanoparticles (NPs) embedded in silica glass (SiO2) are irradiated by swift heavy ions (SHI),
elongation of the NPs, i.e., the transformation from spheres to rods along the ion beam direction, is induced[1-4]. Contrary non-metal NPs of Ge show deformation perpendicular to the ion beam direction, i.e., thedeformation to disk-shape [5]. Although the mechanism of the elongation of metal NPs is still under hot
debate, a practically-assumed criterion is whether the NPs melt by thermal spike effect or not [3,4]. If thecriterion is true, large elongation is expected for NPs with low melting point, e.g., Zn, even though the NP
size is relatively large. On the other hand, ZnO NPs are highly efficient luminescent material. Control ofthe luminescent properties with SHI irradiation via the shape deformation is also attractive, if it is possible.
These demonstrations have been going on in this study.
Zn NPs were formed by implantation of Zn ions of 60 keV to silica glass up to a fluence of 1.0  1017
ions/cm2. No post-implantation annealing was carried out. ZnO NPs were formed by thermal oxidation of
the Zn NPs embedded in silica glass [7]. The samples were irradiated by the SHI of 200 MeV Xe14+ fromthe tandem accelerator at JAEA-Tokai, with an incident angle of 45 deg from the sample surface. The SHI
fluence per unit area of the inclined sample surface (45 deg) was varied from 7.1  1010 to 3.5  1013
ions/cm2.
Optical transmission spectroscopy with linearly-polarized light was conducted with an incident angle ofsurface normal in the wavelength region of 215 – 1700 nm at room temperature. The results are shown in
Fig. 1, in the form of the optical density - log10 T, where T denotes the transmittance. The polarization angleof 0 deg corresponds to the direction of the major axes of elongated NPs. In unirradiated state and at the
fluence of 7.1  1010 ions/cm2, both the polarizations (0 and 90 deg) give the identical spectrum, indicatingthat the NPs are in spherical forms. At the fluence of 7.1  1011 ions/cm2, small but clear deviation is visible
between the 0 and 90 deg polarizations. This is one of the evidence of the elongation of NPs. With
increasing the SHI fluence, the spectrum of the 0 deg polarization shifts to the high energy side, while thatof the 90 deg polarization shifts to the low energy side. These behaviors are ascribed to further elongationof the NPs. More clear evidence of the elongation of NPs was obtained by cross-sectional transmission
electron microscopy (XTEM).
irradiation to 3.5  10

13

Fig. 2 shows the XTEM images in (a) unirradiated state and (b) after theions/cm2. While NPs are in the spherical shapes before the irradiation, NPs areelongated along the beam direction as shown in Fig. 2(b). It should be noted again that the samples were
irradiated with an incident angle of 45 deg from the surface normal.

1
2

National Institute for Materials Science (NIMS)
Japan Atomic Energy Agency (JAEA)- 111 -

JAEA-Review 2010-056

Consequently, it was shown that the elongation of Zn NPs in SiO2 is induced by SHI irradiation. Also thelinearly-polarized optical spectroscopy was confirmed as a sensitive detection method for the elongation of
metal NPs in SiO2.

3200 MeV Xe=> Zn:SiO2- Log10 T

0 Xe/cm21

14+

7.1x1010

7.1x1011

7.1x1012

3.5x1013

2

90 deg
0 deg

0
2

4

6

PHOTON ENERGY (eV)Fig. 1 Optical density spectra of Zn NPs in silica
glass in unirradiated state and after irradiation of
200 MeV Xe14+ ions to four different fluences.
Linearly polarized light with the polarization of 0
and 90 deg was used. The spectra are verticallyshifted with each other for clarity and the horizontal
lines indicate the base lines.

Fig. 2 Cross-sectional TEM images of Zn
NPs in silica glass in (a) unirradiated state
and after (b) irradiation of 200 MeV Xe+
ions to a fluence of 3.5  1013 Xe/cm2. As
indicated by an arrow in (b), the sample wasirradiated with an incident angle of 45 degfrom the surface normal.

References[1] C. D'Orleans et al., Phys. Rev., B67 (2003) 220101.
[2] A Oliver et al., Phys. Rev., B74 (2006) 245425.
[3] K. Awazu et al., Phys. Rev., B78 (2008) 054102.
[4] F. Singh et al., Nucl. Instrum. Methods Phys. Res., B267 (2009) 936-940.
[5] B. Schmidt et al., Nucl. Instrum. Methods Phys. Res., B257 (2007) 30-32.
[6] H. Amekura et al., Nanotechnology 18 (2007) 395707.
[7] H. Amekura and N. Kishimoto, Springer Lecture Notes in Nanoscale Science and Technology Vol. 5,
Springer, Dordrecht, Heidelberg, London, New York (2009) 1-75.

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JAEA-Review 2010-056

7.7

Elongation of Au nanoparticle in SiO2 matrix irradiated with swift heavy ionsM. Shirai 1 , K. Yasuda1, S. Matsumura1 and N. Ishikawa2

Nanogranular thin films, in which nanometer-size particles are embedded in nonmagnetic or opticaltransparent matrix, attract a great attention as various functional new materials, such as for ultrahighdensity magnetic recording media. We have investigated morphological change in nanoparticles induced byion irradiation in order to control the size, shape and dispersion [1,2]. Ion irradiations of 2.4 MeV Cu and
210 MeV Xe ions were found to induce elongation of FePt nanoparticles in amorphous Al2O3 matrix along
ion-beam directions. The present report deals with the morphological change in Au nanoparticles embeddedin SiO2 matrix induced by with 210 MeV Xe ions.
Nano-granular thin film with Au-nanoparticle in SiO2 matrix was fabricated on Si wafer substrate by aseries of chemical reactions with use of APTS (3-Amino-Propyl-Triethoxy-Silicate) solution, TEOS
(Tetrasthoxy sililane) and Chloroauric acid (HAuCl4). Prepared thin film specimens were finally annealedin air at 1173 K for 2 hours to homogenize and densify SiO2 matrix. The detailed procedure of thespecimen preparation has been reported elsewhere [3]. Figure 1(a) shows a cross sectional bright-field
image of the fabricated thin film specimen, in which Au nanoparticles were embeded in amorphous SiO2
matrix. The thickness of SiO2 matrix was ranged from 100 to 300 nm depending on the position of the film.
Gold nanoparticles were distributed rather homogeneously with diameter ranging from 5 to 60 nm asshown in Fig.1 (b). The shape of the Au nanoparticles was confirmed to be spherical before ion irradiation.
These specimens were irradiated with 210 MeV Xe ions at ambient temperature at the Tandem Accelerator
Facility of JAEA-Tokai to fluence ranging from 1.0×1017 to 1×1019 ions/m2. The electronic stopping powerof 210 MeV Xe ions in the film were evaluated to be 48 and 15 keV/nm for Au and SiO2 phase,respectively, at the specimen surface. Morphological changes in the nanoparticles were examined bytransmission electron microscopy with cross-section samples at High Voltage Electron Microscopy
Laboratory, Kyushu University.
Figure 2(a) is an example of bright-field image of the thin film specimen irradiated with 210 MeV Xe ionsto 1x1018 ions/m2. It is seen that a part of Au nanoparticles is elongated along the ion beam direction. Size
distribution of Au particles is shown in Fig.2 (b) as functions of the sizes perpendicular (D) and parallel(DII) to the ion beam direction. The Au particles are seen to elongate parallel to the ion beam direction
especially for the larger particles. The elongation of Au particles was observed at fluence higher than
5x1017 ions/m2, which suggests the existence critical fluence, or critical overlapping times for theobservable elongation of Au particles. Another interesting point is that no significant morphologicalchanges were observed for smaller particles less than 20 nm. This is consistent with previously reported
results in Pt nanoparticles in SiO2 matrix irradiated swift Au ions [4].
12Department of Applied Quantum Physics and Nuclear engineering, Kyushu University
Tokai Research Center, Japan Atomic Energy Agency- 113 -

JAEA-Review 2010-056

8070D⊥ (nm)

60
50
40
30
20
10
0
0

10

20

30

40

50

60

70

80

Dll (nm)Fig. 1 Bright-field cross section view of thin film specimen before ion irradiation (a), illustrating
Au nanoparticles in SiO2 matrix. Size distribution of Au nanoparticles as functions of diameters
measured parallel and perpendicular to the direction to film thickness (b).
80
70D⊥ (nm)

60
50
40
30
20
10
0
0

10

20

30

40

50

60

70

80

Dll (nm)Fig. 2 Bright-field cross section view of the thin film specimen irradiated at ambient temperature with
210 MeV Xe ions to a fluence of 1x1018 ions/m2 (a). The direction of ion irradiation was perpendicular to
the film thickness direction. Size distribution of Au nanoparticles as functions of diameters measured
parallel and perpendicular to the direction to film thickness or ion beam direction (b).
References[1] M. Shirai et al., Mater. Trans., 47 (2006) 52[2] M. Shirai et al., Nucl. Instrum. Methods Phys. Res., B267 (2009) 1787.
[3] M. Shirai, doctoral thesis, Kyushu University (2010) (in Japanese).
[4] M.C. Ridgway et al., Nucl. Instrum. Methods Phys. Res., B267 (2009) 931.

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JAEA-Review 2010-056

7.8 Radiation damage test for Virtex-5 FPGAY. Yamada 1 , T. Tanaka2, T. Inamori2, H. Idobata2, Y. Nagame3, K. Tsukada3, T. K. Sato3,
S. Mitsuoka3 and K. Nishio3
We performed the radiation damage test for Virtex-5 FPGA (Field Programmable Gate Array), which weare planning to use our astrometric satellite named Nano-JASMINE (JASMINE is the abbreviation ofJapan Astrometric Satellite Mission for Infrared Exploration) using the tandem accelerator at JAEA-Tokai.
Nano-JASMINE will be launched at Aug. 2011 from Alcantara launch site by Cyclone 4 launch vehicle.
The purpose of the test is to evaluate the error frequency in orbit radiation environment. At satellite orbit,
error occurs in electric devices operation due to the radiation [1]. There are two types of errors, single
event effect and total dose effect.
effect.

This experiment is planned to evaluate the probability of single event

We should take measures to deal with the error, for example, use expensive radiation hard devices,

implements error correction software and etc.

We first measure the error frequency for considering theway we can do against the error.
For such tests, we expose high LET beam (30 MeV/micro g / cm2) at radiation sensitive region of thedevice, and monitor error behavior.

Furthermore, the FPGA has circuit connection point at the surface.

For expose the beam under operating the device, the beam should be exposed from the leer side of thedevice.

We shave the device until 100 micro m.

after passing 100 micron Si layer.

The beam is required to have 30 MeV/micro g / cm2

For this, the beam energy behind the Si is larger than 80 MeV.

this reason, we use 650, 622.8, 600, and 588.5 MeV Ni beam.

For

The beam is available by using the tandem

accelerator and booster.
The fluence rate is 6.5 / sec in average.
than we can count.
chopper.

If the fluence rate is large, the error occurs with higher frequency

We cannot realize such low fluence in accelerator beam condition.

We use beam

6

The beam fluence at upstream is about 1.6 x 10 / sec and the beam can go to downstream in

only 1 micro second in every 250 ms.
Evaluation of the on-orbit frequency of the error is ordinary performed in two steps.
relation between LET and the error frequency.

First we get theSecond, multiplying LET distribution of on-orbit radiation

environment and the frequency we get, and integrated it by LET.

For the first steps, the relation between

LET and the probability of single event effect is well approximated by Weibull function [2],  x  x0  S  F ( x)  A 1  exp   ,

W


 
 

1

Kyoto University
University of Tokyo
3
Japan Atomic Energy Agency (JAEA)
2- 115 -

JAEA-Review 2010-056

where x is LET, A, x0, W, and S are unknown parameters.
the error probabilities with several LETs.
region of the device.

For determining these parameters, we measure

The formula is applicable to the LET at the radiation sensitive

The beam energy decreases after going through the Si layers.

We computed thebeam energy by SRIM.
We can have the relation between injected ion LET and an error frequency. By using this, we evaluatedthe error frequency in on-orbit environment to be 1 time / 10 days.

This value is acceptable for

Nano-JASMINE satellite.
Now, the ultra-small satellite becomes exciting. Traditionally, satellites were made by national space
agencies using huge amount of money.

In such cases, very expensive – about a thousand times more

expensive than the devices used on the ground – radiation-resistent devices are available.
satellite, such expensive hardware could not available.

But for small

On the other hand, high performance of thepresent day electric devices can be reached by high density implementation of circuits.

Generally

speaking, the frequency of error due to radiation becomes larger when the circuit density becomes high.
The evaluation of Virtex-5’s availability may be helpful for other satellite mission which needs highperformance CPUs.

Table 1. Experimental results and estimated cross sections.
EnergyErrorsExposure time

Incident particles

Error rate

Cross section

650 MeV

60

1788 s12675

1/29.8

2.63×10-03 cm2

622.8

80

2248

17010.5

1/29.92.56×10-03

600

18

5257

29393

1/292

2.50×10-04

588.5

3

3648

20936.5

1/1216

4.21×10-05

References[1] Holmes-Siedle, A. G., and Adams, Len, “Handbook of Radiation Effects”, Oxford Science Publications(1993).
[2] E. Normand and T. J. Baker, IEEE Trans. Nucl. Sci., 40 (1993), 40.

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JAEA-Review 2010-056

7.9Transport properties of (-FeSi2) thin films
S. Okayasu１ and M. Sasase２

Iron disilicide (-FeSi2) is one of the candidates of compound semiconductor, which contains harmless
elements to the human bodies, natural resources and the environment [1]. Another attractive feature of
-FeSi2 is transformation to the metal phase -FeSi2 when heated above 1246 K. Since the bulk -FeSi2
has electric resistivity as low as 2.5 x 10-4  cm, one may consider if a small part of -FeSi2 can betransformed into -FeSi2 selectively, it can be used as the electrode of a -FeSi2 based device.
When high-energy heavy ions are irradiated into materials, most of their energies are dissipated through anelectronic excitation [2]. This leads to strong localization of the dissipated energy along the projectile path.
The density of energy deposition is high enough, compared with bond or displacement energy of the target
materials, so that nanostructural changes take place such as amorphization and phase transition etc. We
attempted to perform phase transition from -FeSi2 into other phase by the high-energy heavy ion
irradiation.

The specimens used in this study were -FeSi2 films fabricated with the ion beam sputter deposition
method by depositing Fe on Si(100) substrates with the thickness 500 nm at certain temperatures [3]. In ourprevious report, we obtained preliminary transport data which the sign of Hall coefficient alternates withtemperature. The simplest interpretation of this result is the altertating of transport carriers from holes toelectrons with temperature. However, we have to confirm where the most part of current flows in a FeSi2
layer or Si substrate. We are conducting careful transport measurements.
Our results showed only the structural change by high energy heavy ion irradiations with different electric
stopping power Se. No phase transition of -FeSi2 to  phase is confirmed yet with the irradiations at room
temperature. Therefore, we make a plan to irradiate the samples at high temperature near the transition.

References[1] K. Yamaguchi and K. Mizushima, Phys. Rev. Lett., 25 (2001) 6006.
[2] M. Toulemonde, S. Bouffard and F. Studer, Nucl. Instrum. Methods Phys. Res., B91 (1994) 108.
[3] M. Sasase et al., Thin Solid Films, 401 (2001) 73.

1
2

Japan Atomic Energy Agency (JAEA)
The Wakasa-wan Energy Research Center (WERC)- 117 -

JAEA-Review 2010-056

7.10

Formation of metal microstructure induced by ion irradiation in Ag-zeolite
S. Okayasu１ and Y. Sasaki２

Zeolite, a sort of alminosillicate constructed with degenerated SiO4 and AlO4 tetrahedrons sharing oxygen
atoms with their neighbors, has a cage structure including large porous inside. Alkali or alkaline earth
cations ( usually Na+ ) of the same amount of Al3+ ions are absorbed in the cage structure to compensate thecharge imbalance. The molecular formula of zeolite can be expressed as(MⅠ,MⅡ1/2)m(AlmSinO2(m+n))・xH2O : n≧m(1),

where MⅠand MⅡare univalent and divalent cations included inside the cage. A crystal structure of a
LTA-zeolite is classified into type-A ( a ratio of Si/Al =1 ) . The alkali or alkaline earth cations inside thecage structure are easily replaced other cations Ag+, Mn2+, etc. We synthesized Ag-zeolite samples forirradiation study.
In our previous study, we found the separation and clustering of Ag atom after 200keV electron irradiation
on Ag-LTA zeolite samples. In the next stage of our study, we try to align the clusters along heavy ion
tracks. Synthesized Ag-zeolite samples were irradiated with 200MeV Au ions in the Tandem accelerator in
JAEA at room temperature with a fluence of 1x1011 ions/cm2. We prepared the sample for the crosssectional observation of Transmission Electron Microscope (TEM). A result is shown in Fig.1. The Ag
clusters are aligned along the ion tracks. We apply for a patent on the phenomenon (2009-213741).



100nm



Au-200MeV

Fig. 1 A photo of cross-section TEM of
Au-irradiated Ag-LTA zeoilte. Ag clusters are
Aligned Agaligned along ion tracks.

clusters

12Japan Atomic Energy Agency (JAEA)
Japan Fine Ceramics Center (JFCC)- 118 -

JAEA-Review 2010-056

7.11 Angular dependences of flux pinning properties
in YBCO thin films with crossed columnar defects
T. Sueyoshi 1 , T. Sogo1, K. Yonekura1, T. Fujiyoshi1, F. Mitsugi1, T. Ikegami1 and N. Ishikawa2

The columnar defects (CDs) formed by the heavy-ion irradiation into high-Tc superconductors have been
known to be the most typical one-dimensional 1-D pinning centers (PCs) and are effective for the large
enhancement of the in-field critical current density Jc at B || c and the reduction of the anisotropy of Jc
which is one of the serious problems for the practical applications of superconductors [1]. The heavy-ion
irradiation also enables us to produce the crossed 1-D PCs consisting of a finite number of the CD
directions around c-axis. Several groups have reported the experimental enhancements of Jc due to thecrossed CDs compared to the parallel CDs [2]. Most of these experiments, however, has been carried out
only for the enhancement of Jc at B || c, and therefore the effect of the crossed CDs on the angulardependence of critical current density Jc() has not been well-studied yet. In this work, the influence of thedispersion in the directions of the 1-D PCs on the Jc() is systematically investigated in YBa2Cu3Oy(YBCO) thin films.
Samples used in this work were c-axis oriented YBCO thin films prepared by the pulsed laser deposition(PLD) method on SrTiO3 substrates. The CDs were produced by irradiating the samples at room
temperature with 200MeV Xe ions from a tandem accelerator at JAEA-Tokai. To install the crossed CDs,
the incident ion beam was tilted off the c-axis by i and was always directed perpendicular to the longer
direction bridge of the sample so that the crossed CDs consist of two parallel CD families at i relative tothe c-axis. As a reference, a sample with the parallel CDs inclined at i relative to the c-axis was prepared.
The total density of CDs corresponds to the dose equivalent matching field B = 2 T. The transport
properties were measured using the four probe method. The transport current was applied in the direction
perpendicular to the magnetic field, the c-axis, and the CDs at any time. The critical current density Jc wasdefined by a criterion of the electrical field E = 1 V/cm. The Jc() was evaluated under the magnetic field,
where  is the angle between the magnetic field and the c-axis of the film. In case of the samples with thecrossed CDs, the magnetic field was rotated in a splay plane where two parallel CD families are crossing
each other.
Fig. 1 shows the Jc() properties for (a) sp10 (i=10) and (b) sp45 (i=45), respectively. Generally, thepeak at  = 90 is attributed to the stacking faults or to the intrinsic pinning due to the CuO2 planes. In
contrast, the additional peak around  = 0 originates from the introduced CDs. For sp10, the shapes of theadditional peaks are sharp and single around B || c. This would be ascribed to the splay effect, in which the
suppression of motion of flux lines from one CD to another is caused by the slight dispersion in the
direction of CDs [3]. For sp45, on the other hand, the crossover from a broad peak around B || c to double

1
2

Kumamoto University
Japan Atomic Energy Agency (JAEA)- 119 -

JAEA-Review 2010-056

peaks at two directions of the irradiation is observed. In lower magnetic fields, the pre-existed c-axis
correlated PCs such as screw or edge dislocations would be effective around  = 0. This would bereflected in the plateau observed in Jc() of sp45 at 1.5 T within the angle range from 45 to 45. As themagnetic field increases, the pre-existed c-axis correlated PCs would be weak and the two parallel CDfamilies dominantly affect the Jc() so that the double peaks appear at =45. To discuss the differences of
the additional peaks among the configurations of the CDs quantitatively, we adopt a simple approach, inwhich the additional peak is characterized by defining two parameters as its height and width; the height of
the additional peak is evaluated from the ratio of the value of the peak, Jcp to the minimum value of Jc(),Jcm [4] and the width a is defined as the difference between angles of Jcp and Jcm [5]. In Fig. 2(a), theJcp/Jcm initially increases with magnetic field and reaches a maximum around a half of B for all irradiatedsamples. For B > B, the decreases of Jcp/Jcm in the crossed configurations are more pronounced comparedto those in the parallel configuration (pa06). The dispersion in the direction of CDs would prevent thecorrelation of flux pinning along the c-axis in high magnetic fields, which occurs in the parallel CD
configurations due to the collective pinning of flux lines including the interstitial flux lines between the
directly pinned flux lines by CDs. In Fig. 2 (b), the values of a, which approximately represent theaccommodation angle where the flux pinning by CDs effectively disappears, abruptly decrease withincreasing magnetic field in the crossed CD configurations for B > B. One of reasons for this is that thesliding of the flux lines along one of the two parallel CD families occurs in the magnetic field tilted off thec-axis [6]. In high magnetic fields, the interstitial flux lines appear between the CDs. There is a possibility
that the interstitial flux lines slide along one of the two parallel CD families, which also promotes the
motion of flux lines pinned along the other one through the elastic interaction.
B = 1.5T

109

Jc[A/m ]Jcp / Jcm

2.5T
2

3T

(a)

pa06
sp10
sp25
sp45

2

2T

1.5

(a) sp101
B = 1.5T

a [ deg. ]

109

60

2T
2.5T
3T

-50

0

 [deg.]

(b)

pa06
sp10
sp25
sp45

40
20

(b) sp45

50

0
0

100

Fig. 1 Angular dependence of Jc at 77.3K and
1T for (a) sp10 and (b) sp45.
References[1] L. Civale et al., Phys. Rev. Lett., 67 (1991) 648.
[2] L. Krusin-Elbaum et al., Phys. Rev. Lett., 76 (1996) 2563.
[3] T. Hwa et al., Phys. Rev. Lett., 71 (1993) 3545.
[4] S. Awaji et al., Appl. Phys. Lett., 90 (2007) 122501.
[5] L. Civale et al., Appl. Phys. Lett., 84 (2004) 2121.
[6] Th. Schuster et al., Phys. Rev., B50 (1994) 9499.

- 120 -

2

4
B[T]

6

Fig. 2 Magnetic field dependence of (a)Jcp/Jcm and (b) a at 77.3 K.

JAEA-Review 2010-056

7.12

Swift ion implantation for fabrication of optical waveguides
F. Qiu1, T. Narusawa1, A. Osa2 and M. Sataka2

The optical waveguide is not only one of key elements in integrated optical circuits but also it has several
possibilities as active and/or passive optical devices. In order to fabricate various waveguides (different
substrates including glasses and crystals) effectively as well as easily, the present study utilizes swift Ar ion
implantation with energy of 60MeV and dose of 2×1012 ions/cm2. Due to relatively large electronic
stopping cross sections of swift and heavy Ar ions, the planar waveguide structure can be fabricated withseveral orders smaller dosages than conventional ion implantation.
The substrates used in the present study are listed in Table 1 together with the ideas behind the choice ofeach material. After the implantation, the prism-coupling method was used to observe the guided opticalmodes in these samples. We have found that planar waveguides are certainly formed in these substrates,
except for Er:Yb:Phosphate glass. Figure 1 shows the results from GLSO glass and Nd:MgO:LiNbO3 (TEmode at the wavelength of 632.8nm). Sharp downward cusps in Fig.1 indicate guided optical modes. The
reason why the Er:Yb:Phosphate glass was no good is yet to be resolved.
After carefully polishing the end-faces of these waveguides, the near-field intensity distributions have beenmeasured by the end-fire coupling method. We have so far obtained the distributions for Nd:MgO:LiNbO3
and Nd:YAG. Figure 2 shows the result for Nd:YAG (TM0 mode at the wavelength of 632.8nm). As we cansee from the intensity distribution curve, only one mode (the fundamental mode) propagates in the
waveguide. This is requisite for waveguide laser operation and the finding is encouraging for our future
works.

Table 1 Substrates for swift ion implantation and possible applications
Substrate materials

Idea of applications

Nd:MgO:LiNbO3

Solid-State Laser with Emission at 1085nm

Nd:YAG

Solid-State Laser with Emission at 1030nm

Nd:YVO4

Solid-State Laser with Emission at 914, 1064
and 1342nm

KTP (KTiOPO4)

Second Harmonic Generation

Nd:GLS Glass

Solid-State Laser with Emission at 1080nm

Ho:GLS Glass

Solid-State Laser with Emission at 3040nm

Er:Yb:Phosphate Glass

Er Doped Waveguides Amplifier

Gallium Lanthanum Sulphide (GLS) andGallium Lanthanum Oxysulfide (GLSO)
Glasses

Infrared Transmission from Telecommunication
Windows to Long-Wavelength Infrared_________________________________________
1
Kochi University of Technology (KUT)
2
Japan Atomic Energy Agency (JAEA)- 121 -

Relative Intensity of Light (%)

JAEA-Review 2010-056

90

(a)

80
70
60
50
2 .3 02 .2 92 .2 82 .2 72 .2 6

E ffe c tiv e R e fr a c tiv e I n d e x(b)Fig. 1 Prism-coupling results for (a) GLSO glass (b) Nd:MgO:LiNbO3

Fig. 2 Near-field intensity distribution for Nd:YAG(The inset numbers are digitizer units and dimensionless)
In future works, we will measure the optical loss of these waveguides and the lasing properties. The
relationship of the refractive index change and the implantation-induced damages will also be studied.

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JAEA-Review 2010-056

7.13

Dynamic nuclear polarization study of meso-scale spatial distribution of free
radicals generated by carbon and electron beams
T. Kumada 1 , Y. Noda1 and N. Ishikawa1

Dynamic nuclear polarization (DNP) results from transferring spin polarization from electrons to nuclei by
microwave, thereby aligning the nuclear spins to the extent that electron spins are aligned. Polarization
PDNP achieved by DNP is determined by a balance between the build-up rate A of the nuclear polarizationand spin-lattice relaxation rate T1n-1 of nuclear spins,

PDNP AA  T1n

1

Pe ,

(1)

where Pe is the electron polarization at the thermal equilibrium. Both larger A and smaller T1n-1 are essential
for higher P. In most of DNP studies, the nuclear polarizations are built up by the cross effect (CE) andthermal mixing (TM), Both of the CE and TM rely on a three electron-electron-nucleus spin flip processes,
whose efficiency depends on two electron-electron spin interactions. High concentration Ce of free radicals
is essential not only to increase microwave absorbance for DNP but also to increase the electron-electron
spin interaction for the CE and TM. On the other hand, T1n-1 increases with increasing Ce. Ce should be
optimized based on a compromise over two conflicting requests for larger A and smaller T1n-1.
Because of multi-spin processes, DNP should be sensitive not only to Ce but also to the heterogeneity of thespatial distribution of the polarizing agents. We came up with the idea that the DNP technique can be used
for the study of meso-scale spatial distribution of free radicals produced by radiolysis of solid materials. In
this study, we compare DNP results of C6+- and electron-beam irradiated low-crystallinity polyethylene(e-LPE, C-LPE) with TEMPO-doped one (T-LPE), (2,2,6,6-tetramethylpiperidine 1-oxyl) to discuss thespatial distribution of free radicals produced by these beams by the analysis of DNP results.
C-LPE was prepared by irradiation of C6+ (100 MeV) ion beams to the total dose of 109 – 1013 ions / cm2 to
LPE sheets with the thickness of 0.5 mm on a bottom tip of a cryostat cooled by liquid nitrogen. Electron
beams (2 MeV, 0.2-2 mA, 2 s  30 min.) for e-LPE was irradiated at JAEA Takasaki in a similar manner.
T-LPE was prepared by a permeation of TEMPO vapor in glassware under vacuum at 330 K for 1 day. Ceof alkyl radicals for C-LPE and e-LPE, and that of TEMPO for T-LPE were determined by ESR at 77 K.
We took care to avoid absorption of oxygen molecules in air, which enhance nuclear spin relaxation andsuppress PDNP. The DNP measurements were carried out at 1.2 T and 1.5 K with microwave of 34.5 GHz.
Figure 1 shows enhancements of polarization compared with thermally equilibrated proton polarization at
1

Japan Atomic Energy Agency (JAEA)- 123 -

JAEA-Review 2010-056
4.2 K PTE(4.2K). The T-LPE showed a sharp maximum for Ce = 4  1019 spins / cm3. The e-LPE also
showed a maximum but less significant. The enhancement of PDNP for C-LPE was much less than that for
T-LPE and e-LPE, and poorly depended on Ce. We found that the build-up and decay rates of the proton
polarizations rather than PDNP more remarkably depend on Ce. Figs. 2 and 3 show the build-up rate andT1n-1 determined by grow and decay behaviors of PDNP after switching on and off of the microwave,
respectively. T1n-1  Ce2 was obtained for T-LPE, but T1n-1  Ce was for C-LPE. E-LPE showed T1n  Ce-1
below Ce = 7  1019 spins cm-3 but T1n  Ce-2 above. Although the relation for Ce was less clear, A for
C-LPE and e-LPE depend less on Ce than that for T-LPE.
The efficiency of DNP by CE and TM depends both on absorbance of microwave and dipolar electron
spin-spin interaction. The absorbance linearly increases with Ce. On the other hand, the dipolar spin-spin
interaction increases in proportional to local concentration of free radicals, where they are localized. It is
known that free radicals produced by C6+-beam are localized along the path of the track of the beams, andelectron-beams generate spur, blobs, and short tracks, where 3-4 or more free radicals are localized,
whereas the TEMPO free radicals are homogeneously distributed in T-LPE. Therefore, although it can bereferred to as Ce for T-LPE, the local concentration for C-LPE and e-LPE is independent of Ce as long as
the spurs, blobs and tracks do not overlap for each other, whereas it increases in proportional to Ce for
T-LPE. Since T1n-1 behaved in a similar manner as A, the main proton-spin relaxation path is also assigned
as the three electron-electron-nucleus spin flip process. The steeper dependence of T1n-1 on Ce above Ce = 7
 1019 spins cm-3 for e-LPE than that below is probably due to overlap of spurs, blobs, and short tracks at
higher radiation dose.

In this way, heterogeneity of free-radical distribution can be studied by the analysis of powerfunction of the build-up and decay of PDNP as a function of Ce. We hope that this techniquewould be a general technique to measure sizes of the spurs, blobs, and tracks produced byradiolysis of non-metallic solids.
100

10
T-LPE
C-LPE
e-LPE

80

10

10

-1

10

-2

T-LPE
C-LPE
e-LPE

20
10

0

18

10

Fig. 1

19

20

10
10
3
Ce (spins / cm )PDNP(1.5K) / PTE(4.2K).

10

-2

10

-3

10

-4

1

-1

-1

T 1n (s )

40

-1

1

A (arb.)

PDNP,1.5K / PTE,4.2K

10

T-LPE grow
T-LPE decay
C-LPE grow
C-LPE decay
e-LPE grow
e-LPE decay

0

2
60

0

-3

18

19

10

10
10
3
Ce (spins / cm )Fig. 220

Build-up rate.

- 124 -

10

2

18

19

10
10
3
Ce (spins / cm )Fig. 3T1n-1.

20

JAEA-Review 2010-056

7.14

Track characterization of oxygen ions in solid state track detector
M. Tampo 1 , K. Nishio2, Y. Fukuda1, H. Sakaki1, S. Mitsuoka2 and K. Kondo1

The ion track detector consisting of organic polymer is one of the highly sensitive detectors that can catch asingle ion and is insensitive to x-rays, gamma-rays and electrons. It is then appropriate to detect ion signals
from an ultra-intense-laser created plasma, which simultaneously generates intense electrons, x-rays andgamma-rays with p-sec bunch. The detector reveals the ions as a few micron pit by chemically etching an
ion damaged trail, which is created along ion incidental path. The diameter of pits depends on ion energy
and species. This ion track response has been investigated under the ambient air conditions. Track diameter
also has dependency on vacuum condition since a creation mechanism of ion track also depends on oxygen
dissolving into the detector [1]. However, track response under vacuum is not understood well in heavyions. Then, it is required to know what species ions are accelerated from the cluster gas target from theinteraction between an ultra-intense-laser light and a He-CO2 gas cluster target under the condition of
vacuum [2], In this report, we describe an experimental investigation to assign the vacuum effect of ion
track response for MeV Oxygen ions on the ion track detector in different energy range.
Irradiation by Oxygen ions of the ion track detectors was conducted in JAEA Tandem Accelerator. As ion
track detector, we used sheets of a plastic track detector called as CR-39 (BARYO TRACK delivered from
FUKUBI Co. Ltd.) with 0.1mm thickness. The detector was stacked with several sheets to resolve different
energy ranges by energy filtering due to the stopping power of each CR-39 sheet. The stacked CR-39
detector was irradiated with a 286 MeV Oxygen beam after being accelerated in booster line. The beam
fluence was reduced by as much as 106/cm2 with beam flipper. To investigate the vacuum effect, thestacked CR-39 was placed under vacuum at 10-7 torr, varying time durations during which the stacked
CR-39 is in vacuum before the irradiation by the Oxygen beam. The time durations were 1, 3, and 7 hour
before the irradiation. The stacked CR-39 was separated into the single sheets on removal from the chamber,and then etched by a 6N-KOH solution at 70 degree Celsius. The step of etching and pit observation by an
optical microscope was repeated with 3times so that we could obtained a time development of pit diameterswith 0.5, 1.5 and 3hour in different energy ranges as shown in Fig. 1.
Figure 1 shows that shorter time placement of the CR-39 in vacuum results in more effective enlargementof pit diameter. This result can be interpreted that sensitivity of track creation strongly depends on a densityof Oxygen gas dissolved into the CR-39 since such oxygen gas is degassed by vacuum. This oxygen effectfor track creation has been discussed in the case of protons and alpha particles, when decreasing of theoxygen1
2

Photo-Medical Research Center, Kansai Photon Science Institute of Japan Atomic Energy Agency (JAEA)
Advanced Science Research Center, Japan Atomic Energy Agency (JAEA)- 125 -

JAEA-Review 2010-056

B1 (vac pre 7hour) pit diameter at 0.5hour (um)B1 (vac pre 7hour ) pit diameter at 1.5hour (um)B1 (vac pre 7hour) pit diameter at 3.0hour (um)B2 (vac pre 3hour) pit diameter at 0.5hour (um)B2 (vac pre 3hour) pit diameter at 1.5hour (um)B4 (vac pre 1hour) pit diameter at 0.5hour(um)B4 (vac pre 1hour) pit diameter at 1.5hour (um)B4 (vac pre 1hour ) pit diameter at 3.0hour (um)Fig. 1

12

Pit diameters of Oxygenions related to ion energy,

10time duration of vacuum

Pit Diameter (um)placement

andetchingtime. Ion energies were

8

evaluated with stopping
energy range of CR-39

6

using SRIM code. Error ofpit diameter was 20% at
0.5hour etch and 5% at 1.5

4

and 3.0 hour etch.

2
0
0.1

2

4
6
8 10 12 14 16
Energy of Oxigen Ions (MeV/n)

18density from degassing by vacuum brings reduction of track creation sensitivity [3]. Our result also shows
the reduction of track creation sensitivity even for heavy ions such as oxygen, which means oxygen gas
effect plays an important role of track creations. On the other hand, we are discussing a track response atshort time etching in Fig. 1. While we varied time duration placing the CR-39 in vacuum as 1, 3, and 7 hour,difference of pit diameter at 0.5 hour etching was not big change. This can be discussed a possibility of
track creation mechanism independent on the density of Oxygen gas.
References[1] T. Yamauchi et al., Nucl. Instrum. Methods Phys. Res., B208 (2003) 489-494.
[2] Y. Fukuda et al., Phys. Rev. Lett., 103 (2009) 165002.
[3] B. Dorschel et al.,Radiation Measurerements., 40 (2004) 234-239.

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JAEA-Review 2010-056

CHAPTER 8
Publication in Journal and Proceedings andContribution to Scientific Meetings

8.1 Accelerator Operation and Development
8.2 Nuclear Structure
8.3 Nuclear Reaction
8.4 Nuclear Chemistry
8.5 Nuclear Theory
8.6 Atomic Physics and Solid-state Physics
8.7 Radiation Effects in Materials- 127 -

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JAEA-Review 2010-056

8.1 Accelerator Operation and Development
Journal/Proceedings
T. Ishii, M. Matsuda, H. Kabumoto and A. Osa
Recent Activities in Tandem, Booster and TRIAC at Tokai
Perspectives in Nuclear Physics, Proc. 6th Japan-Italy Symposium on Heavy-Ion Physics,(2008) ; AIP Conf. Proceedings, 1120 (2009) 235-240.
M. Okada, K. Niki, S. Arai and I. Katayama
Development of multi layer chopper
Proc. 6th Particle Accelerator Society Meeting of Japan, (2009) 1114-1116.
K. Niki, H. Ishiyama, M. Okada, H. Miyatake, Y.X. Watanabe, S. Arai and H. Makii
Design of the 2-4 MHz pre-bunch system at TRIAC
Proc. 6th Particle Accelerator Society Meeting of Japan, (2009) 1117-1119.
Y. Otokawa, A. Osa, T.K. Sato, M. Matsuda, S. Ichikawa and S.C. Jeong
Development of radioactive ion beam production systems for Tokai Radioactive Ion Acceleration Complex-High temperature ion source for short-lived isotopes
Rev. Sci. Instrum., 81 (2010) 02A902.
H. Kabumoto, S. Takeuchi, N. Ishizaki, T. Yoshida, T. Ishiguro and K. Yamaguchi
Recovery of acceleration field gradients of superconducting booster resonators by high pressure water jet
rinsing
Proc. 6th Particle Accelerator Society Meeting of Japan, (2009) 1120-1122.
H. Kabumoto, S. Takeuchi, M. Matsuda, N. Ishizaki and Y. Otokawa
Superconducting twin quarter wave resonator for acceleration of low velocity heavy ions
Proc. 14th Int. Conf. on RF superconductivity, (2009) 849-853.
H. Kabumoto, S. Takeuchi, M. Matsuda, N. Ishizaki and Y. Otokawa
Superconducting twin quarter wave resonator for acceleration of low velocity heavy ions
Nucl. Instrum. Methods Phys. Res., A612 (2010) 221-224.
H. Kabumoto, S. Takeuchi, N. Ishizaki, T. Yoshida, T. Ishiguro and K. Yamaguchi
Recovery of superconducting booster’s performance by high pressure water jet rinsing
Proc. 22nd Meeting for Tandem Accelerators and their Associated Technologies, UTTAC-J-18, (2009)129-132.
M. Matsuda, T. Ishii, Y. Tsukihashi, S. Hanashima, S. Abe, A. Osa, N. Ishizaki, H. Tayama, T. Nakanoya, H.

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Kabumoto, M. Nakamura, K. Kutsukake, Y. Otokawa and T. Asozu
Present Status of JAEA-Tokai Tandem Accelerator
Proc. 22nd Meeting for Tandem Accelerators and their Associated Technologies, UTTAC-J-18, (2009)10-14.
M. Matsuda, T. Asozu, K. Kutsukake, T. Nakanoya, S. Hanashima and S. Takeuchi
Use of an ECR ion source in the large electrostatic accelerator
Proc. 6th Particle Accelerator Society Meeting of Japan, (2009) 827-829.
M. Matsuda, T. Asozu, T. Nakanoya, K. Kutsukake, S. Hanashima and S. Takeuchi
Highly charged ion injector in the terminal of tandem accelerator
J. Phys. Conf. Ser., 163 (2009) 012112.
M. Matsuda
Use of an ECR ion source in the large electrostatic accelerator
J. Particle Accelerator Society of Japan, 6 (2009) 213-221.
S. Hanashima
Present status of the control system of JAEA-Tokai tandem accelerator
Proc. 22nd Meeting for Tandem Accelerators and their Associated Technologies, UTTAC-J-18 (2009) 65.
T. Asozu, M. Makoto, K. Kutsukake and M. Nakamura
Influence of the median potential in an electrostatic steerer
Proc. 22nd Meeting for Tandem Accelerators and their Associated Technologies, UTTAC-J-18 (2009)123-126.
T. Nakanoya, H. Tayama, H. Kabumoto, M. Matsuda and Y. Tsukihashi
Emission Management of SF6 gas at the JAEA-Tokai tandem accelerator
Proc. 22nd Meeting for Tandem Accelerators and their Associated Technologies, UTTAC-J-18 (2009) 66-68.

Meetings
T. Ishii
Recent Activities at Tokai Tandem Accelerator
Nuclear Physics Trends: 7th China-Japan Joint Nuclear Physics Symposium, Tsukuba, Japan (Nov. 9-13,
2009).
M. Okada, K. Niki, S. Arai and I. Katayama
Development of multi layer chopper
Particle Accelerator Society Meeting 2009, Tokai, Japan (Aug. 5-7, 2009).

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K. Niki, H. Ishiyama, M. Okada, H. Miyatake, Y. Watanabe, S. Arai and H. Makii
Design of the 2-4 MHz pre-bunch system at TRIAC
Particle Accelerator Society Meeting 2009, Tokai, Japan (Aug. 5-7, 2009).
K. Niki, H. Ishiyama, M. Okada, H. Miyatake, Y. Watanabe, S. Arai and H. Makii
Development of the 2-4 MHz pulsed ion beams for measurement of 12C(, )16O reaction
Annual meeting of the Physical Society of Japan, Okayama, Japan (Mar. 20-23, 2010).
Y. Otokawa, A. Osa, T. K. Sato, M. Matsuda, S. Ichikawa and S. C. Jeong
Development of radioactive ion beam production systems for Tokai Radioactive Ion Acceleration Complex-High temperature ion source for short-lived isotopes
13th Int. Conf. on Lon Sources, Gatlinburg, U.S.A. (Sep. 20-25, 2009).
H. Kabumoto, S. Takeuchi, N. Ishizaki, T. Yoshida, T. Ishiguro and K. Yamaguchi
Recovery of acceleration field gradients of superconducting booster resonators by high pressure water jet
rinsing
Particle Accelerator Society Meeting 2009, Tokai, Japan (Aug. 5-7, 2009).
H. Kabumoto, S. Takeuchi, M. Matsuda, N. Ishizaki and Y. Otokawa
Superconducting twin quarter wave resonator for acceleration of low velocity heavy ions14th Int. Conf. on RF superconductivity, Berlin, Germany (Sep. 20-25, 2009).
H. Kabumoto, S. Takeuchi, N. Ishizaki, T. Yoshida, T. Ishiguro and K. Yamaguchi
Recovery of superconducting booster’s performance by high pressure water jet rinsing
22nd Meeting for Tandem Accelerators and their Associated Technologies, Tsukuba, Univ. of Tsukuba,
Japan (Jul. 16- 17, 2009).
M. Matsuda, T. Ishii, Y. Tsukihashi, S. Hanashima, S. Abe, A. Osa, N. Ishizaki, H. Tayama, T. Nakanoya, H.
Kabumoto, M. Nakamura, K. Kutsukake, Y. Otokawa and T. Asozu
Present Status of JAEA-Tokai Tandem Accelerator
22nd Meeting for Tandem Accelerators and their Associated Technologies, Tsukuba, Japan (Jul. 16-17,
2009).
M. Matsuda, T. Asozu, K. Kutsukake, T. Nakanoya, S. Hanashima and S. Takeuchi
Use of an ECR ion source in the large electrostatic accelerator
Particle Accelerator Society Meeting 2009, Tokai, Japan (Aug. 5-7, 2009).
S. Hanashima
Present status of the control system of JAEA-Tokai tandem accelerator
22nd Meeting for Tandem Accelerators and their Associated Technologies, Tsukuba, Japan (Jul. 16-17,- 131 -

JAEA-Review 2010-056

2009).
T. Asozu, M. Makoto, K. Kutsukake and M. Nakamura
Influence and measures of the median potential in electrostatic steerers on beam optics
Particle Accelerator Society Meeting 2009, Tokai, Japan (Aug. 5-7, 2009).
T. Asozu, M. Makoto, K. Kutsukake and M. Nakamura
Influence of the median potential in an electrostatic steerer
22nd Meeting for Tandem Accelerators and their Associated Technologies, Tsukuba, Japan (Jul. 16-17,
2009).
M. Nakamura, M. Matsuda, M. Sataka, K. Takahiro and N. Matsunami
Heavy ion Rutherford backscattering spectrometry (HIRBS) at JAEA Tokai Tandem accelerator
Annual Meeting of the Physical Society of Japan, Okayama, Japan (Mar. 20-23, 2010).
T. Nakanoya, H. Tayama, H. Kabumoto, M. Matsuda and Y. Tsukihashi
Emission Management of SF6 gas at the JAEA-Tokai tandem accelerator
22nd Meeting for Tandem Accelerators and their Associated Technologies, Tsukuba, Japan (Jul. 16-17,
2009).

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8.2 Nuclear Structure
Journal/Proceedings
Y. H. Zhang, M. Hasegawa, W. T. Guo, M. L. Liu, X. H. Zhou, G. de Angelis, T. M. Axiotis,
A. Gadea, N. Marginean, Martinez, D. R. Napoli, C. Rusu, Zs. Podolyak, C. Ur, D. Bazzacco,
F. Brandolini, S. Lunardi, S. M. Lenzi, R. Menegazzo, R. Schwengner, A. Gargano, W. von Oertzen
and S. Tazaki
High-spin level structure in 94,95Mo
Phys. Rev., C79 (2009) 044316.
Y. H. Qiang, Y.H. Zhang, X.H. Zhou, Y. Liu, J. Hu, M.Oshima, H. Harada, M. Koizumi, K. Furutaka,
F. Kitatani, S. Nakamura, Y. Toh, A. Kimura, Y. Hatsukawa, M. Ohta, K. Hara, T. Kin and J. Meng
High-spin level structure of odd-odd 168Ta
Sciences in China, G39 (2009) 2-10.
W. Hua, X.H. Zhou, Y.H. Zhang, Y.X. Guo, M. Oshima, Y. Toh, M. Koizumi, A. Osa, B. Qi, S.Q. Zhang,
J. Meng and M. Sugawara
Study of the vi−113/2 band in 189Pt
Chinese Phys., C33 (2009) 743-747.
Y.H. Zhang
High-spin states of odd-odd nuclei in the A  170 mass region
Nucl. Phys., A 834 (2010) 32c–35c.
W. Hua, X. H. Zhou, Y. H. Zhang, Y. Zheng, M.L. Liu, F. Ma, S. Guo, L. Ma, S.T. Wang, N.T. Zhang,
Y.D. Fang, X.G. Lei, Y.X. Guo, M. Oshima, Y. Toh, M. Koizumi, Y. Hatsukawa, B. Qi, S.Q. Zhang,
J. Meng and M. Sugawara
Properties of the rotational bands in the transitional nucleus 189Pt
Phys. Rev., C80 (2009) 034303.
H. Iimura and F. Buchinger
Charge radii in modern macroscopic-microscopic mass models: The role of dynamic quadrupole
deformation
Eur. Phys. J., A42 (2009) 559-563.

Meetings
D. Nagae, T. Ishii, R. Takahashi, M. Asai, H. Makii, A. Osa, T.K. Sato, S. Ichikawa, Y.R. Shimizu and
T. Shoji
Lifetime Measurements for the First 2+ States in 162, 164Gd Populated by the  Decay of 162, 164Eu
Int. Symp. on Exotic Nuclei, Sochi, Russia (Sep. 29, 2009).

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H. Hayashi, M. Shibata, M. Asai, A. Osa, T.K. Sato, M. Koizumi, A. Kimura and M. Oshima
Beta decay energy measurements of 160-165Eu with a total absorption clover Ge detector
Symp. on Slow and Stop Radioisotope, Tokyo, Japan (Mar. 2, 2010).
H. Hayashi, M. Shibata, M. Asai, A. Osa, T.K. Sato, M. Koizumi, A. Kimura and M. Oshima
Beta decay energy measurements of A~160 nuclei using total absorption detector
Annual meeting of the Physical Society of Japan, Okayama, Japan (Mar. 20-23, 2010).
H. Hayashi, M. Shibata, M. Asai, A. Osa, T.K. Sato, M. Koizumi, A. Kimura and M. Oshima
Study on nuclear data by using a high intensity pulsed neutron source for advanced nuclear system: (10)
Measurements of beta-decay energies
Spring meeting of the Atomic Energy Society of Japan, Mito, Japan (Mar. 26-28, 2010).
M. Asai, K. Tsukada, Y. Kasamatsu, T. K. Sato, A. Toyoshima, Y. Ishii, R. Takahashi, Y. Nagame, T. Ishii, I.
Nishinaka, D. Kaji, K. Morimoto and Y. Kojima
Alpha-gamma coincidence spectroscopy of 259Rf using a mixed Cf target
3rd Joint Meeting of the Nuclear Physics Division of the APS and JPS, Waikoloa, U.S.A. (Oct. 13-17,2009).
M. Asai, K. Tsukada, Y. Kasamatsu, T. K. Sato, A. Toyoshima and Y. Nagame
Production of long-lived Fm and Es tracers using a Cf target and its application to nuclear spectroscopy
53th Symp. on Radiochemistry, Tokyo, Japan (Sep. 28-30, 2009).
N. Imai, Y. Hirayama, H. Ishiyama, S.C. Jeong, H. Miyatake, Y.X. Watanabe, H. Makii, S. Mitsuoka,
D. Nagae, I. Nishinaka, K. Nishio and K. Yamaguchi
Isobaric analog resonance of 69Zn by thick target inverse kinematics proton resonance scattering
Direct Reaction with Exotic Beams 2009, Tallahassee, U.S.A. (Dec. 16-19, 2009).
N. Imai, Y. Hirayama, H. Ishiyama, S.C. Jeong, H. Miyatake, Y.X. Watanabe, H. Makii, S. Mitsuoka,
D. Nagae, I. Nishinaka, K. Nishio and K. Yamaguchi
Neutron single particle states in neutron-rich nuclei studied by proton resonance scattering
Int. workshop on “Physics with Stopped and Slow Radioisotope Beams”, Tokyo, Japan (Mar. 1-2, 2010).

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8.3 Nuclear Reaction
Journal/Proceedings
K. Nishio, H. Ikezoe, S. Mitsuoka, I. Nishinaka, Y. Watanabe, Y. Nagame, T. Ohtsuki, K. Hirose andS. Hofmann
Effects of nuclear orientation on fusion and fission process in heavy ion reactions
Proc. 6th Japan-Italy symposium on Heavy-Ion Physics, ASR2008, AIP Conf. Proc., 1120 (2009) 275- 279.
K. Nishio, H. Ikezoe, S. Mitsuoka, I. Nishinaka, Y. Watanabe, Y. Nagame, T. Ohtsuki, K. Hirose andS. Hofmann
Effects of nuclear orientation on fission fragment mass distributions in the reactions of 34,36S + 238U.
Proc. New Aspects of heavy Ion Collisions Near the Coulomb Barrier, AIP Conf. Proc., 1098 (2009) 289–294.
K. Nishio, H. Ikezoe, S. Mitsuoka, I. Nishinaka, Y. Watabnabe, Y. Nagame, T. Ohtsuki, K. Hirose andS. Hofmann
Effects of nuclear orientation on fission fragment mass distributions for the reactions using actinide
target nuclei
Proc. 4th Int. Workshop on Nuclear Fission and Fission Products Spectroscopy, AIP Proc. Conf., 1175
(2009) 111-118.

I. Nishinaka
Nuclear-charge polarization at scission in fission from moderately excited light-actinide nuclei
Proc. 2009 Int. Congress on Advances in Nuclear Power Plants, The Atomic Energy Society of Japan,
CD-ROM (2009) 93112-1-6.
I. Nishinaka, M. Tanikawa, Y. Nagame and H. Nakahara
Nuclear-charge polarization at scission in proton-induced fission of light actinides
AIP Conf. Proc., 1098 (2009) 320-325.
H. Ikezoe, S. Mitsuoka, K. Nishio, Y. Watanabe, S. C. Jeong, I. Nishinaka, T. Ohtsuk and K. Hirose
Dependence of barrier distribution and fusion-fission process on entrance channel
Nucl. Phys., A834 (2010) 172c-175c.
A.N. Andreyev, S. Antalic, D. Ackermann, L. Bianco, S. Franchoo, S. Heinz, F.P. Hessberger, S. Hofmann,
M. Huyse, I. Kojouharov, B. Kindler, B. Lommel, R. Mann, K. Nishio, R.D. Page, J.J. Ressler, P. Sapple,
B. Streicher, S. Saro, B. Sulignano, J. Thomson, P. Van Duppen and M. Venhart
Alpha decay of 194At
Phys. Rev., C79 (2009) 064320(1-12).

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F. P. Heßberger, S. Antalic, B. Sulignano, D. Ackermann, S. Heinz, S. Hofmann, B. Kindler,
J. Khuyagbaatar, I. Kojouharov, P. Kuusiniemi, M. Leino, B. Lommel, R. Mann, K. Nishio, A. G. Popeko,
Š. Šáro, B. Streicher, J. Uusitalo, M. Venhart and A. V. Yeremin
Decay studies of K isomers in 254No
Eur. Phys. J., A43 (2010) 55-66.
H. Ishiyama, T. Hashimoto, K. Yamaguchi, Y.X. Watanabe, N. Imai, Y. Hirayama, H. Miyatake,
M.H. Tanaka, N. Yoshikawa, S.C. Jeong, Y. Fuchi, I. Katayama, T. Nomura, T. Ishikawa, S.K. Das,
Y. Mizoi, T. Fukuda, K. Nishio, S. Mitsuoka, H. Ikezoe, M. Matsuda, S. Ichikawa, T. Shimoda, K. Otsuki
and T. Kajino
A Systematic Study of Astrophysical Reaction Rates through Li
AIP Conf. Proc., 1120 (2009) 177-182.
T. Hashimoto, H. Ishiyama, Y.X. Watanabe, Y. Hirayama, N. Imai, H. Miyatake, S.C. Jeong, M.H. Tanaka,
N. Yoshikawa, T. Nomura, S. Mitsuoka, K. Nishio, T.K. Sato, A. Osa, S. Ichikawa, M. Matsuda, H. Ikezoe,
S.K. Das, Y. Mizoi, T. Fukuda, A. Sato, T. Shimoda, K. Otsuki and T. Kajino
A new measurement of the astrophysical 8Li(d, t)7Li reaction
Phys. Lett., B674 (2009) 276-280.
H. Ishiyama, T. Hashimoto, T. Ishikawa, K. Yamaguchi, Y.X. Watanabe, Y. Hirayama, N. Imai, H. Miyatake,
M-H. Tanaka, N. Yoshikawa, S.C. Jeong, Y. Fuchi, T. Nomura, I. Katayama, H. Kawakami, S. Arai,
M. Okada, M. Oyaizu, S. Mitcuoka, A. Osa, T.K. Sato, K. Nishio, M. Matsuda, S. Ichikawa, H. Ikezoe,
Y. Mizoi, S.K. Das, T. Fukuda, T. Shimoda, K. Otsuki and T. Kajino
Determination of astrophysical nuclear reaction rates using light neutron-rich RNBs
Proc. Science (NIC X), (2009) 134 (5pp).

Meetings
K. Nishio, H. Ikezoe, S. Mitsuoka, I. Nishinaka, H. Makii, Y. Watanabe, Y. Nagame, T. Ohtsuki, K. Hirose
and S. Hofmann
Measuremet of the quasifission properties in the reactions of 30Si, 31P, 40Ar + 238U
Fall meeting of the Atomic Energy Society of Japan, Sendai, Japan (Sep.16-18, 2009).
K. Nishio, S. Hofmann, F.P. Hessberger, D. Ackermann, S. Antalic, V.F. Comas, Ch.E. Duellmann,
A. Gorshkov, R. Graeger, S. Heinz, J.A. Heredia, K. Hirose, H. Ikezoe, J. Khuyagbaatar, B. Kindler,
I. Kojouharov, B. Lommel, R. Mann, S. Mitsuoka, Y. Nagame, I. Nishinaka, T. Ohtsuki, A.G.. Popeko,
S. Saro, M. Schaedel, A. Tuerler, Y. Watanabe and A.V. Yeremin
Effects of nuclear deformation of 238U on the fission fragment mass distribution in the reaction of 30Si +238

U

Annual meeting of the Physical Society of Japan, Okayama, Japan (Mar.20-23, 2010).

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JAEA-Review 2010-056

K. Nishio, S. Hofmann, F.P. Hessberger, D. Ackermann, S. Antalic, V.F. Comas, Ch.E. Duellmann,
A. Gorshkov, R. Graeger, S. Heinz, J.A. Heredia, K. Hirose, H. Ikezoe, J. Khuyagbaatar, B. Kindler,
I. Kojouharov, B. Lommel, R. Mann, S. Mitsuoka, Y. Nagame, I. Nishinaka, T. Ohtsuki, A.G.. Popeko,
S. Saro, M Schaedel, A. Tuerler, Y. Watanabe and A.V. Yeremin
Effects of nuclear deformation of 238U on the fission fragment mass distribution in the reaction of 30Si +238

U

Spring meeting of the Atomic Energy Society of Japan, Mito, Japan (Mar.26-28, 2010).
K.Nishio, H.Ikezoe, S. Mitsuoka, I. Nishinaka, Y. Nagame, K. Hirose, T. Ohtsuki, S.Hofmann,
Effects of nuclear orientation on fusion and fission in the reaction using 238U target nucleus
Compound Nuclear Reactions and Related Topics, Bordeaux, France (Oct.05-08, 2009).
K. Nishio
Effects of nuclear orientation on fusion and fission process for reactions using actinide target nucleus
Workshop on Super-heavy Element Chemistry, RIKEN, Wako, Japan (Feb.2, 2010).
K. Nishio, H. Ikezoe, S. Hofmann, F.P. Heßberger, D. Ackermann, S. Antalic, V.F. Comas, Ch.E. Düllmann,
A. Gorshkov, R. Graeger, S. Heinz, J.A. Heredia, K. Hirose, J. Khuyagbaatar, B. Kindler, I. Kojouharov,
B. Lommel, H. Makii, R. Mann, S. Mitsuoka, Y. Nagame, I. Nishinaka, T. Ohtsuki, A.G. Popeko, S. Saro,
M. Schädel, A. Türler, Y. Watanabe, A. Yakushev and A.V. Yeremin
Effects of nuclear orientation on fusion and fission process for reactions using uranium target nuclei
Int. Symp. on Exotic Nuclei, Sochi, Russia (Sep.28-Oct.2, 2009).
K. Nishio, H. Ikezoe, S. Hofmann, F.P. Heßberger, D. Ackermann, S. Antalic, V.F. Comas, Ch.E. Düllmann,
A.Gorshkov, R. Graeger, S. Heinz, J.A. Heredia, K.Hirose, J. Khuyagbaatar, B. Kindler, I. Kojouharov,
B. Lommel, H. Makii, R. Mann, S. Mitsuoka, Y. Nagame, I. Nishinaka, T. Ohtsuki, A.G. Popeko, S. Saro,
M. Schädel, A. Türler, Y. Watanabe, A. Yakushev and A.V. Yeremin
Effects of nuclear orientation on fusion and fission process for reactions using 238U target nucleus
Tours Symposium on Nuclear Physics and Astrophysics VII, Kobe, Japan (Nov.16-20, 2009).

I. Nishinaka
Nuclear-charge polarization at scission in fission from moderately excited light-actinide nuclei
Int. Congress on Advances in Nuclear Power Plants, Tokyo, Japan (May 10-14, 2009).
I. Nishinaka, Y. Kasamatsu, M. Tanikawa, S. Goto and M. Asai
Sub-barrier fusion hindrance in 19F + 209Bi reaction
Annual Meeting of the Japan Society of Nuclear and Radiochemical Sciences, Tokyo, Japan (Sep.
28-30, 2009).
I. Nishinaka, Y. Kasamatsu, M. Tanikawa, S. Goto, and M. AsaiRadiochemical study of sub-barrier fusion hindrance in 19F + 209Bi reaction- 137 -

JAEA-Review 2010-056

Asia-Pacific Symposium on Radiochemistry '09, Napa, California, USA (Nov. 29-Dec.1, 2009).
S. Mitsuoka, H. Ikezoe, K. Nishio, Y. Watanabe, S.C. Jeong, H. Ishiyama, Y. Hirayama, N. Imai and
H. Miyatake
Barrier distribution of quasi-elastic backward scattering in very heavy reaction systems
Int. Conf. on Nuclear Reactions on Nucleons and Nuclei, Messina, Italy (Oct. 4-9, 2009).
H. Ikezoe, S. Mitsuoka, K. Nishio, Y. Watanabe, S. C. Jeong, I. Nishinaka, T. Ohtsuki and K. Hirose
Dependence of barrier distribution and fusion-fission process on entrance channel
Int. Conf. on Nucleus-Nucleus Collisions, Beijing, China (Aug. 16-21, 2009).
K. Yamaguchi, H. Ishiyama, Y. Mizoi, Y.X. Watanabe, T. Hashimoto, M.-H. Tanaka, H. Miyatake,Y. Hirayama, N. Imai, Y. Fuchi, S.C. Jeong, T. Nomura, S.K. Das, T. Fukuda, H. Makii, S. Mitsuoka, I. Arai,
H. Yamaguchi, S. Kubono, Y. Wakabayashi and S. Hayakawa
Development of the GEM-MSTPC for studies of astrophysical nuclear reaction rates
10th Int. Symp. on Origin of Matter and Evolution of the Galaxies, Osaka, Japan(Mar. 8-Mar. 10, 2010).

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8.4 Nuclear Chemistry
Journal/Proceedings
A. Toyoshima, Y. Kasamatsu, K. Tsukada, M. Asai, Y. Kitatsuji, Y. Ishii, H. Toume, I. Nishinaka, H. Haba,
K. Ooe, W. Sato, A. Shinohara, K. Akiyama and Y. Nagame
Oxidation of element 102, nobelium, with flow electrolytic column chromatography on an atom-at-a-timescale

J. Am. Chem. Soc., 131 (2009) 9180.
Z.J. Li, A. Toyoshima, K. Tsukada and Y. Nagame
Ion-exchange behavior of Zr and Hf as homologues of element 104, Rf, in H2SO4 and H2SO4/HClO4 mixed
solutionsRadiochim. Acta, 97 (2009) 1-6.
Y. Kasamatsu, A. Toyoshima, M. Asai, K. Tsukada, Z.J. Li, Y. Ishii, H. Toume, T.K. Sato, T. Kikuchi,
I. Nishinaka, Y. Nagame, H. Haba, H. Kikunaga, Y. Kudou, Y. Oura, K. Akiyama, W. Sato, K. Ooe,
H. Fujisawa, A. Shinohara, S. Goto, T. Hasegawa, H. Kudo, T. Nanri, M. Araki, N. Kinoshita, A. Yokoyama,
F. Fan, Z. Qin, C.E. Düllmann, M. Schädel, and J.V. Kratz
Anionic fluoro complex of element 105, Db

Chem. Lett., 38 (2009) 1084.

Meetings
Y. Nagame, M. Asai, H. Haba, Y. Kasamatsu, Z.J. Li, T.K. Sato, A. Toyoshima and K. Tsukada
Chemical equilibrium in atom-at-a-time chemistry2009 Asia-Pacific Symposium on Radiochemistry, Napa, U.S.A. (Nov. 29-Dec. 4, 2009).
Y. Nagame, M. Asai, Y. Ishii, T. Kikuchi, Z.J. Li, T.K. Sato, A. Toyoshima, K. Tsukada, Y. Kasamatsu,
H. Haba and K. Akiyama
Chemical investigation of Rf and Db at JAEA
2009 Asia-Pacific Symposium on Radiochemistry, Napa, U.S.A. (Nov. 29 – Dec. 4, 2009).
K. Sueki, Y. Nagasaki, T. Kamitsukasa, K. Akiyama, K. Tsukada, M. Asai, A. Toyoshima and Y. Nagame

Synthesis of water-soluble encapsulated-radioisotope fullerenes
2009 Asia-Pacific Symposium on Radiochemistry, Napa, U.S.A. (Nov. 29-Dec. 4, 2009).
Y. Nagame, K. Akiyama, M. Asai, H. Haba, Y. Ishii, Y. Kasamatsu, Z.J. Li, T.K. Sato, A. Toyoshima and
K. Tsukada,
Aqueous chemistry of Rf and Db
7th Workshop on the Chemistry of the Heaviest Elements, Mainz, Germany (Oct. 11-13, 2009).

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Y. Kasamatsu, A. Toyoshima, M. Asai, K. Tsukada, Z.J. Li, Y. Ishii, T.K. Sato, I. Nishinaka, T. Kikuchi,
Y. Nagame, H. Haba, H. Kikunaga, Y. Kudou, N. Sato, Y. Oura, K. Akiyama, W. Sato, K. Ooe,
H. Fujisawa, A. Shinohara, S. Goto, H. Kudo, M. Araki, N. Kinoshita, M. Nishikawa, A. Yokoyama,
F. Fan, Z. Qin and Ch. E. Düllmann
Anion-exchange experiment of Db with AIDA-II
7th Workshop on the Chemistry of the Heaviest Elements, Mainz, Germany (Oct. 11-13, 2009).
K. Tsukada, Y. Kasamatsu. M. Asai, A. Toyoshima, Y. Ishii, Z.J. Li, T. Kikuchi, T.K. Sato, I. Nishinaka,
Y. Nagame, S. Goto, T. Hasegawa, H. Kudo, H. Haba, Y. Kudou, K. Ooe, H. Fujisawa, W. Yahagi,
W. Sato, A. Shinohara, Y. Oura, T. Nanri, M. Araki, A. Yokoyama and F. L. FanAnion-exchange behavior of Db in HF/HNO3 mixed solution using a new on-line chemical apparatus
8th Actinides Conference (Actinides2009), San Francisco, U.S.A. (July 12-17, 2009).
A. Toyoshima, K. Tsukada, M. Asai, T.K. Sato, Z.J. Li, N. Sato, T. Kikuchi, Y. Kitatsuji, Y. Nagame,
K. Ooe, A. Shinohara, Y. Kasamatsu, H. Haba and E. Julia
Reduction of mendelevium (Md) with electrochemistry
Spring Meeting of the Chemical Society of Japan, Higashi-Osaka, Japan (Mar. 26 -29, 2010).
A. Toyoshima, K. Tsukada, M. Asai, Y. Kitatsuji, Y. Ishii, T.K. Sato, Z.J. Li, N. Sato, T. Kikuchi,
I. Nishinaka, Y. Nagame, Y. Kasamatsu, H. Haba, K. Ooe, A. Shinohara, W. Sato and K. Akiyama
Electrochemistry of the heaviest elements at JAEA
2009 Asia-Pacific Symposium on Radiochemistry, Napa, U.S.A. (Nov. 29-Dec. 4, 2009).
R. Takayama, K. Ooe, W. Yahagi, H. Fujisawa, K. Komori, H. Kikunaga, T. Yoshimura, N. Takahashi,
K. Takahisa, H. Haba, Y. Kudou, Y. Ezaki, A. Toyoshima, M. Asai, Y. Nagame, T. Saito, T. Mitsugashiraand A. Shinohara
Solvent extraction of trivalent actinides with di(2-ethylhexyl) phosphoric acid and thenoyltrifluoroacetone
2009 Asia-Pacific Symposium on Radiochemistry, Napa, U.S.A. (Nov. 29-Dec. 4, 2009).
A. Toyoshima, K. Tsukada, M. Asai, Y. Kitatsuji, T.K. Sato, Z.J. Li, N. Sato, T. Kikuchi, Y. Ishii,
I. Nishinaka, Y. Nagame, Y. Kasamatsu, H. Haba, K. Ooe, A. Shinohara, H. Haba, K. Akiyama and
W. SatoElectrochemical studies of the heaviest actinides
7th Workshop on the Chemistry of the Heaviest Elements, Mainz, Germany (Oct. 11-13, 2009).
A. Toyoshima, K. Tsukada, M. Asai, T.K. Sato, Z.J. Li, N. Sato, T. Kikuchi, Y. Kitatsuji, Y. Nagame,
K. Ooe, A. Shinohara, Y. Kasamatsu and H. Haba
Reduction of element 101, mendelevium, with flow electrolytic column chromatography
53rd Symp. on Radiochemistry, Tokyo, Japan (Sep. 28-30, 2009).

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JAEA-Review 2010-056

Z.J. Li, A. Toyoshima, K. Tsukada, M. Asai, T.K. Sato, T. Kikuchi, N. Sato and Y. Nagame
Cation-exchange behavior of Zr, Hf, and Th in H2SO4/HNO3 mixed solutions–towards to study on sulfate
complexation of 104Rf
53rd Symp. on Radiochemistry, Tokyo, Japan (Sep. 28-30, 2009).
T. K. Sato, K. Tsukada, M. Asai, A. Toyoshima, Y. Kasamatsu, Y. Ishii, Z.J. Li, N. Sato, T. Kikuchi, H.
Haba, S. Goto, H. Kudo and Y. Nagame
Development of an On-line Isothermal Gas Chromatographic Appratus for Db and Sg
2009 Asia-Pacific Symposium on Radiochemistry, Napa, U.S.A (Nov. 29-Dec. 4, 2009).
T.K. Sato, K. Tsukada, M. Asai, A. Toyoshima, Y. Kasamatsu, Z.J. Li, N. Sato, T. Kikuchi, and Y. Nagame
On-line Isothermal Gas Chromatographic Behaviour of Group-5 Elements Nb and Ta as Homologues ofDb
53rd Symp. on Radiochemistry, Tokyo, Japan (Sep. 28, 2009).
N. Sato, M. Asai, K. Tsukada, T.K. Sato, A. Toyoshima, Z.J. Li, X. H. Liang, T. Kikuchi, Y. Nagame andS. Ichikawa
Measurement of the ionization potential of Lr (Z = 103)
6th Int. Workshop on "Physics with Stopped and Slow Radioisotope Beams, Tokyo, Japan (Mar. 1-2, 2010).

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JAEA-Review 2010-056

8.5

Nuclear Theory

Journal/Proceedings
Y. Aritomo

Analysis of dynamical processes using the mass distribution of fission fragments in heavy-ion
reactionsPhys. Rev., C80 (2009) 064604.
Y. Aritomo

Analysis of dynamical process with mass distribution of fission fragment in heavy ion reactions
Eur. Phys. J., Web of Conferences 2(2010) 07004.
R. Kanungo, C. Nociforo, A. Prochazka, T. Aumann, D. Boutin, D. Cortina-Gil, B. Davids, M. Diakaki,
F. Farinon, H. Geissel, R. Gernhauser, J. Gerl, R. Janik, B. Jonson, B. Kindler, R. Knobel, R. Krucken,
M. Lantz, H. Lenske, Y. Litvinov, B. Lommel, K. Mahata, P. Maierbeck, A. Musumarra, T. Nilsson,
T. Otsuka, C. Perro, C. Scheidenberger, B. Sitar, P. Strmen, B. Sun, I. Szarka, I. Tanihata, Y. Utsuno,
H. Weick and M.Winkler
One-Neutron Removal Measurement Reveals 24O as a New Doubly Magic Nucleus
Phys. Rev. Lett., 102 (2009) 152501-1-4.
Y. Utsuno, T. Otsuka, B.A. Brown, M. Honma and T. Mizusaki
Shell evolution in the sd-pf shell studied by the shell model
6th Japan-Italy Symposium on Heavy-Ion Physics, Tokai, Japan (Nov. 11-15, 2008)
AIP Conf. Proc., 1120 (2009) 81-86.
M. De Rydt, G. Neyens, K. Asahi, D.L. Balabanski, J.M. Daugas, M. Depuydt, L. Gaudefroy, S. Grevy,
Y. Hasama, Y. Ichikawa, P. Morel, T. Nagatomo, T. Otsuka, L. Perrot, K. Shimada, C. Stodel, J.C. Thomas,
H. Ueno, Y. Utsuno, W. Vanderheijden, N. Vermeulen, P. Vingerhoets and A. Yoshimi
Precision measurement of the electric quadrupole moment of 31Al and determination of the effective proton
charge in the sd-shell
Phys. Lett., B678 (2009) 344-349.
M. Ionescu-Bujor, A. Iordachescu, S.M. Lenzi, D.R. Napoli, N. Marginean, N.H. Medina, D. Bazzacco,
D. Bucurescu, G.de Angelis, F. Della Vedova, E. Farnea, A. Gadea, R. Menegazzo, S. Lunardi, C.A. Ur,
S. Zilio, T. Otsuka and Y. Utsuno
High-spin structure of 37Cl, intruder excitations, and the sd-fp shell gap
Phys. Rev., C80 (2009) 034314-1-12.

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JAEA-Review 2010-056

T. Nakamura, N. Kobayashi, Y. Kondo, Y. Satou, N. Aoi, H. Baba, S. Deguchi, N. Fukuda, J. Gibelin,
N. Inabe, M. Ishihara, D. Kameda, Y. Kawada, T. Kubo, K. Kusaka, A. Mengoni, T. Motobayashi,
T. Ohnishi, M. Ohtake, N.A. Orr, H. Otsu, T. Otsuka, A. Saito, H. Sakurai, S. Shimoura, T. Sumikama,
H. Takeda, E. Takeshita, M. Takechi, S. Takeuchi, K. Tanaka, K.N. Tanaka, N. Tanaka, Y. Togano,Y. Utsuno, K. Yoneda, A. Yoshida and K. Yoshida
Halo Structure of the Island of Inversion Nucleus 31Ne
Phys. Rev. Lett., 103 (2009) 262501-1-4.
T. Otsuka, T. Suzuki, M. Honma, Y. Utsuno, N. Tsunoda, K. Tsukiyama and M. Hjorth-Jensen
Novel Features of Nuclear Forces and Shell Evolution in Exotic Nuclei
Phys. Rev. Lett., 104 (2010) 012501-1-4.
J.Y. Lee, I. Hahn, Y. Kim, S.W. Hong, S. Chiba and E.S. Soukhovitskii
Optical potentials for nuclear level structures and nucleon interactions data of tin isotopes based on thesoft-rotator model
Phys. Rev., C79 (2009) 064612.

O. Iwamoto, T. Nakagawa, N. Otuka, S. Chiba, K. Okumura, G. Chiba, T. Ohsawa and K. Furutaka
JENDL Actinoid File 2008
J. Nucl. Sci. Tech., 46 (2009) 510.

S. Kunieda, S. Chiba, K. Shibata, A. Ichihara, O. Iwamoto, N. Iwamoto, T. Fukahori and
E.Sh. Soukhovitski
An Extensive Study of the Soft-rotator Model Hamiltonian Parameters for Medium and Heavy Even-even
NucleiJ. Nucl. Sci. Technol., 46 (2009) 914.
F. Minato, S. Chiba and K. Hagino
Fission of heavy Λ hypernuclei with the Skyrme-Hartree-Fock approach
Nucl. Phys., A 831 (2009) 150.
T. Maruyama, T. Tatsumi and S. Chiba
Liquid-gas phase transition in asymmetric nuclear matter at finite temperature
Nucl. Phys., A834 (2010) 561.
M. Kohno and S. Hashimoto

Ξ-nucleus potential and (K-,K+) inclusive spectrum at Ξproduction threshold region
Prog. Theor. Phys., 123 (2010) 157-167.

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JAEA-Review 2010-056

S. Hashimoto, K. Ogata, S. Chiba and M. Yahiro
New Approach for Evaluating Incomplete and Complete Fusion Cross Sections with Continuum-Discretized
Coupled-Channels Method
Prog. Theor. Phys., 122 (2009) 1291-1300.

O.V. Bespalova, I.N. Boboshin, V.V. Varlamov, T.A. Ermakova, B.S. Ishkhanov, S.Yu. Komarov, H. Koura,
E.A. Romanovskii and T.I. Spasskaya
Energies of the Single-Particle Proton 1f and 2p States in the 58,60,62,64Ni Isotopes
Bull. Russian Academy of Science: Physics, 73 (2009) 820-823.
K. Morita, K. Morimoto, D. Kaji, H. Haba, K. Ozeki, Y. Kudou, N. Sato, T. Sumita, A. Yoneda, T. Ichikawa,Y. Fujimori, S. Goto, E. Ideguchi, K. Katori, Y. Komori, H. Koura, H. Kudo, K. Ooe, A. Ozawa,F. Tokanai, K. Tsukada, T. Yamaguchi and A. Yoshida
Decay properties of 266Bh and 262Db produced in the 248Cm + 23Na reaction
J. Phys. Soc. Jpn, 78 (2009) 064201.
T. Tachibana, H. Koura and S. Chiba
Calculation of beta-delayed fission and neutron emission probabilities with the use of gross theory and
KTUY mass formula
JAEA-Conf 2009-004 (2009)129-134.
H. Koura, T. Tachibana and S. Chiba,
Global Properties of Nuclear Decay Modes
JAEA-Conf 2009-004 (2009) 135-140.

Meetings
Y. Aritomo
Analysis of Dynamical process with mass distribution of fission fragments using actinide target nuclei
Int. symp. on Exotic Nuclei, Sochi, Russia (Sep. 28, 2009).

Y. Aritomo
Analysis of dynamical process with mass distribution of fission fragment in heavy ion reactions
2nd Int. Workshop on Compound Nuclear Reactions and Related Topics, Bordeaux, France (Oct. 5,2009).
Y. Aritomo
Fusion-fission and quasi-fission processes in reactions using actinide target nuclei
Int. Conf. on Nuclear Reactions on Nucleons and Nuclei, Messina, Italy (Oct. 8, 2009).

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JAEA-Review 2010-056

Y. Aritomo
Potential energy surface and fission dynamics for heavy and superheavy mass nuclei
Workshop of nuclear data 2009, Tokai, Japan (Nov. 26, 2009).
Y. Aritomo, S. Chiba and S. Hashimoto
Analysis of surrogate reaction with unified model
Annual meeting of the Physical Society of Japan, Okayama, Japan (Mar. 20-23, 2010).
Y. Aritomo, S. Chiba, S. Hashimoto, Y. Utsun and H. Koura
Description of surrogate reaction with unified model
Annual Meeting of the Atomic Energy Society of Japan, Mito, Japan (Mar. 26-28, 2010).
Y. Utsuno, T. Otsuka, B.A. Brown, M. Honma and T. Mizusaki
Shell evolution in N~28 unstable nuclei studied by the shell model
Arctic FIDIPRO-EFES Workshop “Future Prospects of Nuclear Structure Physics”, Saariselkä, Finland(Apr. 20, 2009).
Y. Utsuno and S. Chiba
Towards a microscopic nuclear-structure calculation of medium-heavy and heavy nuclei for the practical
purpose2nd Japan Forum of Nuclear Astrophysics Workshop “Nuclear Data in Japan—Nuclear Energy in the Heaven
and the Earth,” Wako, Japan (Jul. 27, 2009).
Y. Utsuno
Evolution of shell and nuclear structure in the neutron rich region
Third Joint Meeting of the Nuclear Physics Divisions of the APS and JPS, Waikoloa, U.S.A. (Oct. 13-17,2009).
Y. Utsuno, T. Otsuka, B.A. Brown, M. Honma and T. Mizusaki
Shell evolution of exotic nuclei beyond N=28 described by the universal monopole picture
EFES-NSCL Workshop on Perspectives on the Modern Shell Model and Related Experimental Topics, East
Lansing, U.S.A. (Feb. 4, 2010).
Y. Utsuno, T. Otsuka, B.A. Brown, M. Honma and T. Mizusaki
Structure of exotic nuclei around and beyond N=28
Workshop on Exotic Nuclei and Modern Shell Model, Tokyo, Japan (Feb. 9, 2010).
Y. Utsuno and S. Chiba
Description of multi-particle multi-hole states around oxygen isotopes with the p-sd shell model
Annual Meeting of the Physical Society of Japan, Okayama, Japan (Mar. 20-23, 2010).

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JAEA-Review 2010-056

Y. Utsuno and S. Chiba
Theoretical research on surrogate reaction—4. Unified description of multi-particle multi-hole states inoxygen isotopes by the shell model
Annual Meeting of the Atomic Energy Society of Japan, Mito, Japan (Mar. 26-28, 2010).
S. Chiba, E. Sh. Soukhovitskij, R. Capote and J.M. Quesada
A Dispersive, Lane-consistent Coupled-channel Optical Model Based on Soft-rotator Theory for Accurate
Calculation of Nuclear Reaction Data
Int. Cong. on Advances in Nuclear Power Plants, Tokyo, Japan (May 12, 2009).
S. Chiba
Surrogate Project at JAEA
Fall Meeting of the Atomic Energy Society of Japan, Sendai, Japan (Sep. 16-18, 2009).
S. Chiba
Fission Fragment Mass Distribution and r-process Nucleosynthesis
Tours Symp. on Nuclear Physics and Astrophysics VII, Kobe, Japan (Nov. 18, 2009).
S. Chiba
Application of the Surrogate Method to Researches in Nuclear Energy
Annual Meeting of the Physics Society of Japan, Okayama, Japan (Mar. 20-23, 2010).
S. Chiba and O. Iwamoto
Verification of the Surrogate Ratio Method
Annual Meeting of the Atomic Energy Society of Japan, Mito, Japan (Mar. 26-28, 2010).
D. Ichinkhorloo, T. Matsumoto, Y. Hirabayashi, K. Kato and S. Chiba
6

Li+n Inelastic Reactions in the continuum Discretized Coupled channels (CDCC) method

Annual Meeting of the Atomic Energy Society of Japan, Mito, Japan (Mar. 26-28, 2010).
S. Hashimoto, S. Chiba, Y. Aritomo and Y. Utsuno
Theoretical Research on Surrogate Reaction -3. Study of excited states produced by direct reaction processSpring Meeting of the Atomic Energy Society of Japan, Mito, Japan (Mar. 26-28, 2010).
S. Hashimoto, K. Ogata, S. Chiba and M. Yahiro
Analysis of deuteron induced incomplete fusion reactions on heavy targets with Continuum-Discretized
Coupled-Channels method
Annual Meeting of the Physical Society of Japan, Okayama, Japan (Mar. 20-23, 2010).

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JAEA-Review 2010-056

S. Hashimoto, K. Ogata, S. Chiba and M. Yahiro
New Approach with CDCC for Evaluating Incomplete and Complete Fusion Cross Sections
Int. Workshop on Direct Reactions with Exotic Breams, Florida, U.S.A.(Dec. Dec. 13-17, 2009).
H. Koura
Global properties of nuclei and nuclear data -- nuclear masses and related ones -Workshop on Nuclear Data and its Application to Nuclear Astrophysics, Wako, Japan (Apr. 20, 2009).
M.S. Smith, E. Lingerfelt, K. Bucker, C.D. Nesaraja, H. Koura and F. Kondev
Masses of Unstable Nuclei: Visualization and Analysis at nuclearmasses.org
8th Int. Conf. of Radioactive Nuclear Beams, Grand Rapids, U.S.A. (May. 26-30,2009).
K. Morimoto, K. Morita, D. Kaji, H. Haba, K. Ozeki, Y. Kudou, N. Sato, T. Sumita, A. Yoneda, T. Ichikawa,Y. Fujimori, S. Goto, E. Ideguchi, Y. Kasamatsu, K. Katori, Y. Komori, H. Koura, H. Kudo, K. Ooe, A.
Ozawa, F. Kokanai, K. Tsukada, T. Yamaguchi and A. Yoshida
Production and decay properties of 266Hs and its daughter nuclei
53rd Symp. on Radiochemistry, Tokyo, Japan (Sep.28-30, 2009).
D. Kaji, K. Morimoto, N. Sato, H. Haba, T. Ichikawa, E. Ideguchi, H. Koura, Y. Kudou, A. Ozawa, K.
Ozeki, T. Sumita, T. Yamaguchi, A. Yoneda, A. Yoshida and K. Morita
Production and decay properties of a new isotope of 263Hs
53rd Symp. on Radiochemistry, Tokyo, Japan (Sep. 28-30, 2009).
H. Koura
Decay modes and a limit of existence of nuclei in the superheavy mass region
4th Asia-Pacific Symposium on Radiochemistry '09, Napa, U.S.A. (Nov. 29-Dec. 5, 2009).
H. Koura
Decay modes and a limit of existence of nuclei in the heavy and superheavy mass region
Annual Meeting of the Physical Society of Japan, Okayama, Japan (Mar. 20-23, 2010).
M.S. Smith , E.J. Lingerfelt, C.D. Nesaraja, H. Koura and F.G. Kondev
Nuclear Masses: Sharing, Visualization, and Analysis at nuclearmasses.org
APS Spring Meeting in Feb. 2010, Washington DC, U.S.A. (Feb.13-16, 2010).
M.S. Smith, E. Lingerfelt, C.D. Nasaraja, H. Koura and P.G. Kondev
Nuclear Mass Visualization and Analysis at nuclearmsses.org
10th Int. Symp. on Origin of Matter and Evolution of Galaxies, Osaka, Japan (Mar.8-10, 2010).

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JAEA-Review 2010-056

8.6

Atomic Physics and Solid-state Physics

Journal/Proceedings
K. Kawatsura, K. Takahiro, M. Sataka, M. Imai, H. Sugai, K. Ozaki, K. Kawaguchi, H. Shibata andK. Komaki
Coster-Kronig electrons from Nq+ and Oq+ Rydberg states produced in high-energy collisions with He
J. Phys.: Conference Series, 163 (2009) 012048(1-6).
M. Imai, M. Sataka, K. Kawatsura, K. Takahiro, K. Komaki, H. Shibata, H. Sugai and K. Nishio
Equilibrium and non-equilibrium charge-state distributions of 2 MeV/u sulfur ions passing through carbon
foils
Nucl. Instrum. Methods Phys. Res., B267 (2009) 2675.
S.C. Jeong, H. Sugai and M. Yahagi
Diffusion experiment with the accelerated, short-lived radioactive beam of 8Li
BUTSURI, 64 (2009) 687-691 (in Japanese).
N. Matsunami, H. Kakiuchida, M. Tazawa, M. Sataka, H. Sugai and S. Okayasu
Electronic and atomic structure modifications of copper-nitride films by ion impact and phase separation
Nucl. Instrum. Methods Phys. Res., B267 (2009) 2653.

Meetings
N. Matsunami, J. Fukushima, M. Sataka, S. Okayasu H. Sugai and H. KakiuchidaElectrical property modifications of In-doped ZnO films by ion irradiation
15th Int. Symp. Radiation Effects in Insulators, Padova, Italy (Aug. 30-Sept. 4, 2009).
N. Matsunami, M. Sataka, S. Okayasu and H. Kakiuchida
Ion irradiation effects on tungsten-oxide films and charge state effect on electronic erosion
15th Int. Symp. Radiation Effects in Insulators, Padova, Italy (Aug. 30-Sept. 4, 2009).
N. Matsunami, H. Kakiuchida, M. Tazawa, M. Sataka, H. Sugai and S. Okayasu,
Ion irradiation effects on tungsten-oxide films and charge state effect on electronic erosion
Annual Meeting of the Physical Society of Japan, Okayama, Japan (Mar. 20-23, 2010).

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JAEA-Review 2010-056

8.7

Radiation Effects in Materials

Journal/Proceedings
Y.Sasaki and T.Suzuki,
Formation of Ag Clusters by Electron Beam Irradiation on Ag-Zeolite
Materials Transactions, 50 (2009) 1050.
S. Kosugi, Nao Fujita, Y. Zushi, T. Matsui, A. Iwase, N. Ishikawa and Y. Saito
Modification of magnetic properties of FeRh intermetallic compounds by energetic ion beam bombardment
Nucl. Instrum. Methods Phys. Res., B267 (2009) 1612-1615.
A. Iwase, H. Ohno, N. Ishikawa, Y. Baba, N. Hirao, T. Sonoda and M. Kinoshita
Study on the behavior of oxygen atoms in swift heavy ion irradiated CeO2 by means of synchrotron
radiation X-ray photoelectron spectroscopy
Nucl. Instrum. Methods Phys. Res., B267 (2009) 969-972.
M. Shirai , K. Tsumori, M. Kutsuwada, K. Yasuda and S. Matsumura
Morphological change in FePt nanogranular thin films induced by swift heavy ion irradiation
Nucl. Instrum. Methods Phys. Res., B267 (2009) 1787-1791.

Meetings
H. Amekura, N. Ishikawa, K. Mitsuishi, Y. Nakayama, D. Tsuya, Ch. Buchal, S. Mantl and N.Kishimoto
Irradiation effects of swift heavy ions on Zn and ZnO nanoparticles
15th Int. Symp. on Radiation Effects in Insulators, Padova, Italy (Aug. 30-Sept. 4, 2009).
H. Amekura, N. Ishikawa, K. Mitsuishi, Y. Nakayama, D. Tsuya, Ch. Buchal, S. Mantl and N.Kishimoto
Irradiation effects of swift heavy ions on Zn and ZnO nanoparticles
16th Int. Conf. on Surface Modification of Materials by Ion Beams, Tokyo, Japan (Sep. 13-18, 2009).
H. Amekura, N. Ishikawa, K. Mitsuishi, Y. Nakayama, D. Tsuya, Ch. Buchal, S. Mantl and N.Kishimoto
Irradiation effects of swift heavy ions on Zn and ZnO nanoparticles
19th MRS-J Academic Symposium, Yokohama, Japan (Dec. 7-9, 2009).
M. Sasase, K. Shimura, K. Yamaguchi, H. Yamamoto, S. Shamoto and K. Hojou
Sputter etching effect of the substrate on the microstructure of β-FeSi2 thin film prepared by ion beam
sputter deposition method
17th Int. Vacuum Congress, Stockholm, Sweden (July 2-6, 2007).
S. Kosugi, Nao Fujita, Y. Tahara, N. Ishikawa, T. Matsui, F. Horiand and A. Iwase
Effect of high temperature annealing on the irradiation-induced magnetic properties of FeRh alloy- 149 -

JAEA-Review 2010-056

Fall Meeting of the Physical Society of Japan, Kumamoto, Japan (Sep. 25-28, 2009).
M. Shirai, K. Tsumori, K. Yasuda and S. Matsumura,
Modification of Structure and Composition of FePt Nanoparticles Embeded in Amorphous Al2O3 Matrix by
Swift Heavy Ions Irradiation
12th Frontiers of Electron Microscopy in Materials Sciemnce, Sasebo, Japan (Sep.27-Oct.2, 2009).
S. Matsumura, T. Yamamoto and K. Yasuda
Atomic-scale Analysis of Irradiation-induced Structural Change in Magnesium Aluminate Spinel
Compound2009 MRS Fall Meeting, Boston, U.S.A. (Nov. 30-Dec. 4, 2009).
K. Yasuda, M. Etoh, S, Kawasoe, T. Yamamoto and S. Matsumura,
Accumulation of disordered zone in MgAl2O4 irradiated with swift heavy ions
15th Int. Symp. on Radiation Effects in Insulators, Padova, Italy (Aug. 30-Sept. 4, 2009).
N. Ishikawa and K. Takegahara
Radiation damage due to high-density electronic excitation in CeO2 irradiated with high-energy ions
Fall Meeting of the Physical Society of Japan, Kumamoto, Japan (Sep. 25-28, 2009).
N. Ishikawa, H. Sugai and T. Sonoda
Irradiation damage in CeO2 irradiated with high-energy heavy ions
15th Int. Symp. on Radiation Effects in Insulators, Padova, Italy (Aug. 30-Sept. 4, 2009).
T. Sueyoshi, S. Yutani, T. Sogo, A. Adachi, K. Yonekura, T. Fujiyoshi, F. Mitsugi, T. Ikegami, N.
Ishikawa, S. Awaji and K. Watanabe

Angular dependence of critical current densities in YBCO thin films with crossed columnar defects
22nd Int. Symp. on Superconductivity, Tsukuba, Japan (Nov. 3, 2009).
T. Sonoda, M. Kinoshita, N. Ishikawa, M. Sataka, A. Iwase and K. Yasunaga
Clarification of high density electronic excitation effects on the microstructural evolution in UO2
15th Int. Conf. of Radiation Effects in Insulators, Padova, Italy (Aug. 30-Sept. 4, 2009).
T. Kumada, Y. Noda, S. Koizumi and T. Hashimoto
Spatial distribution of electron spins studied by polarized protons and polarized neutrons
Annual Meeting of the Japanese Society of Neutron Science, Tokai, Japan (Dec. 9, 2009).

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CHAPTER 9
Personnel and Committee

9.1

Personnel

9.2

Research Planning and Assessment Committee- 151 -

This is a blank page.

JAEA-Review 2010-056

9.1

Personnel
Department of Research Reactor and Tandem Accelerator
Kiyonobu Yamashita

Director

Tsuyoshi

Kusunoki

Deputy Director

YuichiTerakado

Manager of Administration Section

Masao

SatakaSuehiroTakeuchiDepartment of Research Reactor and Tandem Accelerator
Tandem Accelerator Section ( * General Manager )Scientific Staff
TetsuroIshii*

AkihikoOsa

MakotoMatsudaTechnical Staff
Yoshihiro Tsukihashi
SusumuHanashima

Shin-ichi

Abe

Nobuhiro Ishizaki
Hidekazu Tayama
Takamitsu Nakanoya
Hiroshi

Kabumoto

Masahiko Nakamura
Ken-ichiKutsukake

Yoshinori Otokawa
Takuhiro

Asozu

Entrusted Operators
Takahiro

YoshidaTakayuki

Ishiguro

Kazushi

Yamaguchi

Nobuo

Seki

Teruo

OnoderaHikaruNisugi

Department of Radiation Protection
Facility Radiation Control Section I
Kunio

Kawarai

KatsujiYasu- 153 -

JAEA-Review 2010-056

HayatoHiragaDaisukeHigashiSusumuKinaseAdvanced Science Research Center
Yoshihiko Hatano

Director

Hiroshi

Deputy Director

IkezoeAdvanced Science Research Center
Research Group for Shell Structure and Reaction Properties of Heavy Nuclei far from
Stability ( * Group Leader )Hiroari

Miyatake*

SatoshiChiba

ToshikiMaruyama

Shin-ichi

Mitsuoka

Katsuhisa Nishio
Hiroyuki

Koura

YutakaUtsunoIchiroNishinaka

Hiroyuki

Makii

Daisuke

Nagae(Post Doc. to July 31)

Shintaro

Hashimoto(Post Doc.)

Yasuo

Wakabayashi(Post Doc)Shin-ichi

Ichikawa(to Aug. 31)

Ryuta

Takahashi(Student)

Advanced Science Research Center
Research Group for Nuclear Chemistry of the Heaviest Elements ( * Group Leader )Yuichiro

Nagame*Kazuaki

TsukadaMasatoAsai

Tetsuya K. Sato
AtsushiToyoshima(Senior Post Doc.)Zi JieLi(Post Doc.)

Nozomi

Sato(Post Doc.)

Takahiro

Kikuchi(Student)

Advanced Science Research Center
Research Group for Material Design under Extreme Conditions
SatoruOkayasu- 154 -

JAEA-Review 2010-056

NoritoIshikawa

Hiroyuki

Sugai

Teruo

Kato

(to Sep. 30 )Advanced Science Research Center
Research Group for Strongly Correlated Supermolecules
Takayuki

Kumada

Yohei

Noda

(Post Doc.)

Nuclear Science and Engineering Directorate
Innovative Nuclear Science Research Group ( * Group Leader )Masumi

Oshima*Hideo

HaradaHideki

IimuraMitsuoKoizumiKazuyoshi Furutaka
FumitoKitatani

Shoji

Nakamura

YosukeToh

Atsushi

KimuraYasuki

Nagai(Invited Researcher)

Kaoru

Hara

(Senior Post Doc.)

Tadahiro

Kin(Senior Post Doc.)

FutoshiMinato(Post Doc.)

Nuclear Science and Engineering Directorate
Research Group for Irradiation Field Materials ( * Group Leader )Shiro

Jitsukawa*Nariaki Okubo

Quantum Beam Science Directorate
Laser Accelerator Group
Toshiyuki Shizuma
Takehito

Hayakawa

Quantum Beam Science Directorate
Neutron Imaging and Activation Analysis Group
Yuichi

Hatsukawa

Nuclear Safety Research Center- 155 -

JAEA-Review 2010-056

Reactor Component Reliability Research Group
Yasuhiro

Chimi

Tohru

TobitaHigh Energy Accelerator Research Organization (KEK)- Institute of Particle and Nuclear Studies –Radioactive Nuclear Beams Project Group ( * Group Leader )Sun-Chan Jeong*
Hiroari

Miyatake

Hironobu Ishiyama
YutakaWatanabeNobuakiImai

Yoshikazu Hirayama
Michihiro Oyaizu
IchiroKatayama

Hirokane

Kawakami

Shoji

SuzukiHigh Energy Accelerator Research Organization (KEK)- Accelerator Laboratory Kazuaki

Niki

MasashiOkada- 156 -

JAEA-Review 2010-056

9.2

Research Planning and Assessment Committee

Chairman

Shigeru

KubonoVice Chairman

Ken-ichiro Komaki(Professor, The University of Tokyo)(Professor, National Center for University
Entrance Examination)

MemberTadashiKambara(Senior Scientist, RIKEN)

Kenji

Kimura(Professor, Kyoto University)

NoriakiMatsunami(Associate Professor, Nagoya University)

TetsuoNoro(Professor, Kyushu University)

Tsutomu

Ohtsuki(Associate Professor, Tohoku University)

Tadashi

Shimoda(Professor, Osaka University)

Koichi

Hagino(Associate Professor, Tohoku University)

Motoharu Mizumoto(Adjunct Professor, Tokyo Institute of Technology)

Naotaka

Yoshinaga(Professor, Saitama University)

Yuichi

Hatsukawa(Quantum Beam Science Directorate, JAEA)

Shiro

Jitsukawa(Nuclear Science and Engineering Directorate,
JAEA)

Kazumasa Narumi(Advanced Science Research Center, JAEA)

Tetsuro(Deputy Director, Dep. Research Reactor and

Ishii

Tandem Accelerator, JAEA)
SuehiroTakeuchi(Dep. Research Reactor and Tandem Accelerator,
JAEA)

Masao

Sataka(Dep. Research Reactor and Tandem Accelerator,
JAEA)

Kiichi

Hojo(Advanced Science Research Center, JAEA)

Organizer SecretaryShin-ichi Mitsuoka(Advanced Science Research Center, JAEA)

NoritoIshikawa(Advanced Science Research Center, JAEA)

MasatoAsai(Advanced Science Research Center, JAEA)

HiroshiIkezoe(Deputy Director, Advanced Science ResearchCenter, JAEA)- 157 -

This is a blank page.

JAEA-Review 2010-056

CHAPTER 10
Cooperative Researches and Common Use in JAEA
10.1 Cooperative Research Programs
10.2 Common Use Programs in JAEA

- 159 -

This is a blank page.

JAEA-Review 2010-056

10.1 Cooperative Research Programs
Title

Contact Person & Organization

1. Production of neutron-deficient actinide nuclei with closed
neutron shell 126

Hiroari MIYATAKEHigh Energy Accelerator Research
Organization (KEK)

2. Study of new fission channels populated by quai-fission

Tsutomu OHTSUKI
Tohoku University

3. Reduction of mendelevium using an electrochemistry
apparatus

Atsushi SHINOHARA
Osaka University

4. Sulfate complexation of rutherfordium in H2SO4/HNO3
mixed solution

Hisaaki KUDO
Niigata University

5. Mechanism of grain subdivision process due to irradiation

Takeshi SONODA
Central Research Institute of Electricof FP in UO2Power Industry
6. Metal-semiconductor transition control on a FeSi2 thin filmwith high energy heavy ion irradiations

Masato SASASE
The Wakasa-wan Energy ResearchCenter

7. Nano-fabrication of zeolite with high energy ion
irradiations

Yukichi SASAKI
Japan Fine Ceramics Center

8. Effects on clad material by swift heavy ion irradiation

Takeshi SONODA
Central Research Institute of ElectricPower Industry

9. Electrical property modifications of In-doped ZnO films byhigh-energy ion impact

Noriaki MATUNAMI
Nagoya University

10. Heavy ion irradiation effects on CeO2 including otherelements

Akihiro IWASE
Osaka Prefecture University

11. Charge state evolution of heavy ions passing through solid
targets

Makoto IMAI
Kyoto University- 161 -

JAEA-Review 2010-056

10.1 Cooperative Research Programs (cont.) from FY2007 and FY2008
12. Barrier distribution derived from quasi-electric

Sun-Chan JEONG

backscattering in heavy nucleus-nucleus collision leadingHigh Energy Accelerator Researchto superheavy element production

Organization(KEK)

13. Laser Spectroscopy of the Neutron Deficient Isotopes in
Tungsten Region

Takayashi HORIGUCHI
Hiroshima International University

14. Study of nuclear fission from excited states of heavy
actinide nuclei

Akihiko YOKOYAMA
Kanazawa University

15. Development of spectrometer for in-beam γ-ray
spectroscopy of super-heavy nuclei

Toshiyuki KOUNOTokyo Institute of Technology

16. Development of a method for indirect determination of the(n,) cross sections by in-beam gamma-ray spectroscopy

Hiroari MIYATAKE
KEK

10.1 Cooperative Research Programs (cont.) using TRIAC
Title

Contact Person & Organization

17. Development of accelerator technology for short-lived
radioactive nuclear beam

Sun-Chan JEONG
KEK

18. Development of the GEM-MSTPC for the measurement of
the 8Li(, n)11B reaction

Tomokazu FUKUDA
Osaka Electro-Communication
University

19. Search for highly excited 11Be states in 9Li+d reactions

Takashi TERANISHI
Kyushu University

20. Diffusion coefficient measurements on perovskite-type
lithium ion conductor

Tottori University

21. Diffusion coefficient measurements of perovskite-type
lithium ion conductive oxides
22. Coulomb excitation of

Shigeomi TAKAI

Sun-Chan JEONG
KEK

130

Ba at 1.1 MeV/nucleon

Nobuaki IMAI
KEK

- 162 -

JAEA-Review 2010-056

10.2 Common Use Programs in JAEA
Title

Contact Person & Organization

1. Heavy ion irradiation induced ferromagnetism in
FeRh alloys

Akihiro IWASE
Osaka Prefecture University

2. Elongation of Au nanoparticle in SiO2 matrix irradiated

Syo MATSUMURA
Faculty of Engineering, Kyushu

with swift heavy ions

University
3. High-energy ion impact effects on atomic structure andoptical property of In-doped ZnO films

Noriaki MATUNAMI
Nagoya University

4. Decay study on fission products with on-line isotope

Michihiro SHIBATA
Nagoya University

separator

5. Gas-phase chemistry of Zr and Hf using carbon clustertransport system

Shin-ichi GOTO
Niigata University

6. Zero-degree electron spectroscopy of collision induced
highly charged ions and electronic processes
7. Fission properties of the neutron-deficient nucleus 180Hg
produced in heavy ion reactions

Makoto IMAI
Kyoto University
Andrei N. ANDREYEVThe University of the West of
Scotland8. Shape and property control of Zn and ZnO nanoparticles byswift heavy ions

Hiroshi AMEKURA
National Institute for Materials
Science

9. Angular dependences of flux pinning properties in YBCO
thin films with crossed columnar defects

Tetsuro SUEYOSHI
Graduated School of Kumamoto
University
Yoshiyuki YAMADA

10. Radiation damage test for Virtex5 FPGA

Graduate School of Kyoto University
11. High energy alpha particles emitted from nuclear reaction

Nobuaki IMAI
KEK

12. Swift ion implantation for fabrication of opticalwaveguides

Tadashi NARUSAWA
Kochi University of Technology

13. Indirect determination of neutron radioactive capture crosssection on medium nuclei

Nobuaki IMAI
KEK

14. Systematic study of signature inversion and shapecoexistence in high-spin states of medium-heavy nuclei

Xiao Hong ZHOU
Institute of Modern Physics Chinese
Academy of Science- 163 -

This is a blank page.

国際単位系（SI）
表１．SI 基本単位
SI 基本単位

基本量

名称
記号
長
さメ ートル m
質
量 キログラム kg
時
間秒s
流ア ンペア A
電
熱力学温度 ケ ル ビ ン K
ル mol
物 質 量モ光
度 カ ン デ ラ cd

表２．基本単位を用いて表されるSI組立単位の例
SI 基本単位
組立量
名称
記号
面
積 平方メートルm2
体
積 立法メートルm3
速 さ ， 速 度 メートル毎秒m/s
加速度 メートル毎秒毎秒
m/s2
波
数 毎メートルm-1
密 度 ， 質 量 密 度 キログラム毎立方メートル
kg/m3
面
積
密
度 キログラム毎平方メートル
kg/m2
比
体
積 立方メートル毎キログラム
m3/kg
電
流
密
度 アンペア毎平方メートル
A/m2
磁 界 の 強 さ アンペア毎メートル
A/m
(a)
量 濃度
， 濃 度 モル毎立方メートル
mol/m3
質量
濃度 キログラム毎立法メートル
kg/m3
輝
度 カンデラ毎平方メートル
cd/m2
1
屈
折
率 (b) （数字の） １(b)（数字の） １1
比 透 磁 率

乗数
1024
1021
1018
1015
1012
109
106
103
102
101

活

性 カタール

kat

d

Ｚ
Ｅ

10-2

セ ン チ
ミ
リ

c
m

ペ
テ

タ
ラ

Ｐ
Ｔ

µ
n

ギ
メ

ガ
ガ

Ｇ
Ｍ

マイクロ
ノ
10-9 ナコ
10-12 ピ
10-15 フェムト

キ
ロ
ヘ ク ト
デ
カ

ｋ
ｈ

ト
10-18 ア
10-21 ゼ プ ト
10-24 ヨ ク ト

a
z
y

da

d
°
’

10-3
10-6

p
f

1 d=24 h=86 400 s
1°=(π/180) rad1’=(1/60)°=(π/10800) rad1”=(1/60)’=(π/648000) rad”ha 1ha=1hm2=104m2
L，l 1L=11=1dm3=103cm3=10-3m3t
1t=103 kg

秒
ヘクタール
リットル
トン

表７．SIに属さないが、SIと併用される単位で、SI単位で表される数値が実験的に得られるもの
名称
記号
SI 単位で表される数値
1eV=1.602 176 53(14)×10-19J

電 子 ボ ル ト
ダ ル ト ン
統一原子質量単位eVDa
u

1Da=1.660 538 86(28)×10-27kg
1u=1 Da天

ua

1ua=1.495 978 706 91(6)×1011m

文

単

位

表８．SIに属さないが、SIと併用されるその他の単位
名称
記号
SI 単位で表される数値
バー
ル bar １bar=0.1MPa=100kPa=105Pa
水銀柱ミリメートル mmHg 1mmHg=133.322Pa

s-1 mol(a)SI接頭語は固有の名称と記号を持つ組立単位と組み合わせても使用できる。しかし接頭語を付した単位はもはや
コヒーレントではない。
(b)ラジアンとステラジアンは数字の１に対する単位の特別な名称で、量についての情報をつたえるために使われる。
実際には、使用する時には記号rad及びsrが用いられるが、習慣として組立単位としての記号である数字の１は明示されない。
(c)測光学ではステラジアンという名称と記号srを単位の表し方の中に、そのまま維持している。
(d)ヘルツは周期現象についてのみ、ベクレルは放射性核種の統計的過程についてのみ使用される。
(e)セルシウス度はケルビンの特別な名称で、セルシウス温度を表すために使用される。セルシウス度とケルビンの単位の大きさは同一である。したがって、温度差や温度間隔を表す数値はどちらの単位で表しても同じである。
(f)放射性核種の放射能（activity referred to a radionuclide）は、しばしば誤った用語で”radioactivity”と記される。
(g)単位シーベルト（PV,2002,70,205）についてはCIPM勧告2（CI-2002）を参照。

表４．単位の中に固有の名称と記号を含むSI組立単位の例
SI 組立単位
組立量
SI 基本単位による
名称
記号
表し方
-1
粘
度 パスカル秒
Pa s
m kg s-1
力 の モ ー メ ン ト ニュートンメートル
Nm
m2 kg s-2
表面
張力 ニュートン毎メートル
N/m
kg s-2角
速度 ラジアン毎秒
rad/s
m m-1 s-1=s-1
角
加速度 ラジアン毎秒毎秒
rad/s2
m m-1 s-2=s-2
熱 流 密 度 , 放 射 照 度 ワット毎平方メートル
kg s-3
W/m2
熱 容 量 , エ ン ト ロ ピ ー ジュール毎ケルビン
J/K
m2 kg s-2 K-1
比 熱 容 量 ， 比 エ ン ト ロ ピ ー ジュール毎キログラム毎ケルビン J/(kg K)
m2 s-2 K-1
比 エ ネ ルギ ー ジュール毎キログラム
J/kg
m2 s-2
熱伝
導率 ワット毎メートル毎ケルビン W/(m K) m kg s-3 K-1
体 積 エ ネ ル ギ ー ジュール毎立方メートル J/m3
m-1 kg s-2
電界の強さ ボルト毎メートル
V/m
m kg s-3 A-1
電荷密
度 クーロン毎立方メートル C/m3
m-3 sA
表面
電
荷 クーロン毎平方メートル C/m2
m-2 sA
電 束 密 度 ， 電 気 変 位 クーロン毎平方メートル C/m2
m-2 sA誘
電率 ファラド毎メートル
F/m
m-3 kg-1 s4 A2
透磁率 ヘンリー毎メートル
H/m
m kg s-2 A-2
モ ル エ ネ ル ギ ー ジュール毎モル
J/mol
m2 kg s-2 mol-1
モルエントロピー, モル熱容量 ジュール毎モル毎ケルビン J/(mol K) m2 kg s-2 K-1 mol-1
照 射 線 量 （ Ｘ 線 及 び γ 線 ） クーロン毎キログラム
C/kg
kg-1 sA
吸収線
量率 グレイ毎秒
Gy/s
m2 s-3放射
強度 ワット毎ステラジアン
W/srm4 m-2 kg s-3=m2 kg s-3
放射輝
度 ワット毎平方メートル毎ステラジアン W/(m2 sr) m2 m-2 kg s-3=kg s-3
酵 素 活 性濃 度 カタール毎立方メートル kat/m3
m-3 s-1 mol

記号

ゼ
タ
エ ク サ

日
度
分

表３．固有の名称と記号で表されるSI組立単位
SI 組立単位
組立量
他のSI単位による SI基本単位による
名称
記号
表し方
表し方
（ｂ）
平
面
角 ラジアン(ｂ)
rad
m/m
1
（ｂ）
2/ 2
立
体
角 ステラジアン(ｂ) sr(c)
1
m m
周
波
数 ヘルツ（ｄ）
Hz
s-1
力
ニュートン
N
m kg s-2
圧力
応
力 パスカル,Pa
m-1 kg s-2
N/m2
エ ネ ル ギ ー , 仕 事 , 熱 量 ジュールJNm
m2 kg s-2
仕 事 率 ， 工 率 ， 放 射 束 ワット
WJ/s
m2 kg s-3
電
荷
電気量 クーロン,
CsA
電 位 差 （ 電 圧 ） , 起 電 力 ボルト
VW/A
m2 kg s-3 A-1
静電
容量 ファラドF
C/V
m-2 kg-1 s4 A2
電
気
抵
抗 オーム
Ω
V/A
m2 kg s-3 A-2
コ ン ダ ク タ ン ス ジーメンス
S
A/V
m-2 kg-1 s3 A2
磁
束 ウエーバWb
Vs
m2 kg s-2 A-1
磁
束
密
度 テスラ
T
Wb/m2
kg s-2 A-1
イ ン ダ ク タ ン ス ヘンリーH
Wb/A
m2 kg s-2 A-2
セ ル シ ウ ス 温 度 セルシウス度(ｅ)℃K
光
束 ルーメンlm
cd
cd sr(c)
2
照
度 ルクス
lx
lm/m
m-2 cdBqs-1
放 射 性 核 種 の 放 射 能 （ ｆ ） ベクレル（ｄ）
吸収線量, 比エネルギー分与,
グレイ
Gy
J/kg
m2 s-2カーマ
線量当量, 周辺線量当量, 方向
Sv
J/kg
m2 s-2シーベルト（ｇ）
性線量当量, 個人線量当量
素

表５．SI 接頭語
記号 乗数
接頭語
Ｙ
シ
10-1 デ

表６．SIに属さないが、SIと併用される単位
名称
記号
SI 単位による値
分
min 1 min=60s
時h
1h =60 min=3600 s（a）量濃度（amount concentration）は臨床化学の分野では物質濃度（substance concentration）ともよばれる。
（b）これらは無次元量あるいは次元１をもつ量であるが、そのことを表す単位記号である数字の１は通常は表記しない。

酸

接頭語
ヨ
タ

オングストローム
海
里
バ
ー
ン

Å
Ｍ

１Å=0.1nm=100pm=10-10m
１M=1852m

b

ノ
ネ
ベ

ト
パ
ル

kn
Np
Ｂ

１b=100fm2=(10-12cm)2=10-28m2
１kn=(1852/3600)m/s

ル

dB

ッ
ー

デ

ジ

ベ

SI単位との数値的な関係は、対数量の定義に依存。

エ

表９．固有の名称をもつCGS組立単位
名称
記号
SI 単位で表される数値
ル
グ erg 1 erg=10-7 J

ダ
ポ

イ
ア

ス
ス

ト ー ク
チ
ル

フ
ガ

ォ

ン dyn 1 dyn=10-5N
ズ P 1 P=1 dyn s cm-2=0.1Pa s
ス St 1 St =1cm2 s-1=10-4m2 s-1
ブ sb 1 sb =1cd cm-2=104cd m-2
ト ph 1 ph=1cd sr cm-2 104lx
ル Gal 1 Gal =1cm s-2=10-2ms-2

マ ク ス ウ ｪ ルガ
ウス
エルステッド（ ｃ）

Mx
G
Oe

1 Mx = 1G cm2=10-8Wb
1 G =1Mx cm-2 =10-4T
1 Oe (103/4π)A m-1（c）３元系のCGS単位系とSIでは直接比較できないため、等号「は対応関係を示すものである。

キ
レ
ラ

名称
ュ
リ
ン

レ
ガ

ト

表10．SIに属さないその他の単位の例
記号
SI 単位で表される数値
ー Ci 1 Ci=3.7×1010Bq

ゲ

ン

ン R
ド rad
ム rem
マ γ

1 R = 2.58×10-4C/kg
1 rad=1cGy=10-2Gy
1 rem=1 cSv=10-2Sv
1γ=1 nT=10-9T
1フェルミ=1 fm=10-15m

フェルミ
メートル系カラット

1メートル系カラット = 200 mg = 2×10-4kg

気

ル Torr 1 Torr = (101 325/760) Pa
圧 atm 1 atm = 101 325 Pa

ロ

リ

ー

cal

ク

ロ

ン

µ

ト
標

準

カ
ミ

大

」

1cal=4.1858J（｢15℃｣カロリー），4.1868J（｢IT｣カロリー）4.184J（｢熱化学｣カロリー）

1 µ =1µm=10-6m（第8版，2006年改訂）

この印刷物は再生紙を使用しています