Light Source in 2007
Masahiro KATOHUVSOR Facility, Institute for Molecular Science
1. Status of UVSOR-II
In the fiscal year 2007, we have operated the UVSOR-II accelerators from April ’07 to March ’08.
We had totally 36 weeks for the users operation, 34 weeks in multi-bunch mode and 2 weeks insingle-bunch mode. We had 9 weeks dedicated for machine studies, although one week was canceled
as described later. The monthly statistics of the operation time and the integrated beam current are
shown in Figure 1.
The weekly operation schedule is as follows. On Monday, the machine is operated for machinestudies. From Tuesday to Friday, the machine is operated for users, from 9am to 9pm. The beam
injection is twice a day, at 9am and 3pm. The filling beam current is 350 mA in the multi-bunchmode and 100 mA in the single bunch mode. Occasionally, we operate the machine after 9pm forbeam-line conditioning, free electron laser experiments and so on.
In this fiscal year, we had no major reconstruction on accelerators. Thus, we only had short
shut-downs for maintenance works and for holidays. We had three 1-week shut-down, in May,
September and March, and two 2-week ones in August and around the New Years Day.
In this fiscal year, we had two rather serious troubles. In May, the power supply for the septum
magnet of the storage ring was malfunctioned. Many power transistors were broken and it took about
one week to recover. We exchanged a machine study week, which had been planned in the next weekof this happening, with the users’ week. In October, we had a trouble on a booster synchrotron
magnet. We had an electrical short of a bus bar of the bending magnet to the ground. It was partly
melted down. Fortunately, it was recovered within a few days.

Fig. 1. Monthly statistics of the operation time (left) and of the integrated beam current (right).

92. Improvements
Full Energy Injection
The bending magnet power supply of the beam transport line was replaced in the last March, asshown in Figure 2. The new power supply is capable of transporting the full energy (750 MeV) beam
to the storage ring. The power supplies of the booster synchrotron had been already replaced lastyear, to be compatible with the full energy acceleration.
In April, we have started testing the full-energy acceleration on the booster synchrotron, the beamtransport and the injection to the storage ring [1]. In July, we have started operating the machine withthe full-energy injection in the users’ runs. The injection rate is about 0.5 mA/sec and to reach thefilling current, 350 mA, it takes about 15 minutes. The repetition rate of the injection at 750 MeV
was reduced to 1 Hz, which had been 3 Hz at 600 MeV, not to increase the peak electric power of thebooster synchrotron. Even with this lower repetition rate, the total time required for the injection
procedure is almost the same as before, partly because the acceleration on the storage ring was notnecessary and also because we re-fill the electrons on the remaining electrons at the second injectionof the day.
In the machine studies, we have tested the top-up injection. The electron beam current was
successfully kept constant for more than 30 minutes, as shown in Figure 3. This was just a
demonstration and there are many subjects that we must prepare before introducing this technique tothe users’ runs.

Fig. 2. New Magnet Power Supply for Bending Magnets on Beam Transport Line10

Fig. 3. Top-Up Operation Test. The beam current was kept constant for about 30 minutes.
Progress of New Undulator for BL7U
The new undulator for BL7U, a variable polarization undulator of APPLE-II type, is now opened
for users. A feed-forward system to correct the orbit movement caused by the pole gap changes is
successfully commissioned [2]. The orbit movement is corrected within 10 microns. The users canchange the pole gap from the beam line anytime. They also can change the polarization at a fixed
gap, 100 mm during the runs. A beam lifetime shortening is observed for vertically polarized mode,
which may be caused by the non-linear effect of the undulator on the electron dynamics. Some
sophisticated correction scheme should be introduced.
3. Researches and Developments
Free Electron Laser
The oscillating wavelength of the UVSOR-II Free Electron Laser is approaching the VUV region.
In this fiscal year, an oscillation at 199 nm was realized, as shown in Figure 4 [3]. Laser oscillation
around 190 nm, which seems promising, will be the target of the next fiscal year. By using this highpower laser in deep UV region, some users’ experiments are in progress [4].
To get coherent radiation in even shorter wavelength region, which seems hard to reach with theresonator type free electron laser, coherent harmonic generation (CHG) is under investigation,
collaborating with French researchers. Coherent 3rd harmonics of Ti:Sa laser was successfully
produced and the properties of the radiation and the mechanisms were investigated[5].

11Fig. 4. Spectrum of the UVSOR-II Free Electron Laser at 199 nm
Laser Bunch Slicing
Terahertz coherent synchrotron radiation has been intensively studied by using laser bunch slicing
technique [6]. In this scheme, ultra-short laser pulses are injected to the storage ring. As the result of
the interaction between the laser pulses and an electron bunch in an undulator, a part of the electron
bunch is energy-modulated. As this bunch is proceeding in the ring, the energy-modulated electrons
escape from the interacting part of the bunch and finally a dip is created. Such an electron bunchemits coherent synchrotron radiation in the wavelength region longer than the dip width. If we use afemto-second laser pulse, we can create a dip of sub-millimeter width, which corresponds to theterahertz radiation wavelength. We have demonstrated that, by changing the laser pulse width, we
could control the radiation spectra.
We have developed the laser slicing technique to produce periodic density structures by using
amplitude modulated laser pulses [7]. We have succeeded in producing narrow-band coherent
synchrotron radiation in the uniform magnetic field of the bending magnet. We have also
demonstrated that we could control the spectral peak by changing the modulation frequency, andalso that we could control the spectral width by changing the number of the modulation.

12

Fig. 5. Experimental set-up of the laser bunch slicing
REFERENCES[1] A. Mochihashi et al., in this report[2] K. Hayashi et al., in this report[3] M. Hosaka et al., in this report[4] K. Kobayashi et al., in this report[5] M. Labat, M. Hosaka, A. Mochihashi, M. Shimada, M. Katoh, G. Lambert, T. Hara, Y. Takashima,
M. E. Couprie, Euro. Phys. J. D Vol. 44, No. 1 (2007) 187-200[6] M. Shimada et al., in this report[7] M. Shimada et al., in this report

13

14

Parameters of Injection Linear Accelerator

EnergyLengthFrequency
Accelerating RF Field
Klystron Power
Energy Spread
Repetition Rate

15 MeV
2.5 m
2856 MHz
2π/3 Traveling Wave
1.8 MW~ 1.6 MeV
2.6 HzParameters of Booster Synchrotron

EnergyInjection Energy
Beam Current
Circumference
RF Frequency
Harmonic Number
Bending Radius
Lattice
Betatron Tune
Horizontal
VerticalMomentum Compaction
Repetition Rate

750 MeV
15 MeV
32 mA (uniform filling)
26.6 m90.1 MHz8
1.8 m
FODO × 8
2.25
1.25
0.138
1 Hz (750 MeV)

15

Parameters of UVSOR-II Storage Ring
EnergyInjection Energy
Maximum Stored Current

750 MeV
750 MeV
500 mA (multi bunch)
100 mA (single bunch)
27.4 nm-rad
53.2 m90.1 MHz16
2.2 m
Extended DBA  4(4 m  4) + (1.5 m  4)
100 kV

Natural Emittance
Circumference
RF Frequency
Harmonic Number
Bending Radius
Lattice
Straight Section
RF Voltage
Betatron Tune
Horizontal
VerticalMomentum Compaction
Natural Chromaticity
Horizontal
Vertical
Energy Spread
Natural Bunch Length

3.75
3.20
0.028
-8.1
-7.3
4.2  10-4
108 psElectron Beam Optics of UVSOR-II Storage Ring

Horizontal/verticalbetatronfunctionsanddispersion

function(left),

horizontal/vertical electron beam sizes and beam divergences (right) of UVSOR-II

16

and

Parameters of the insertion devices

Brilliance of radiation from the insertion devices (U3, U5, U6 and U7)
and a bending magnet of UVSOR-II
BL3U In-vacuum Undulator

BL6U In-vacuum Undulator

Number of Periods

50

Number of Periods

26

Period Length

38 mm

Period Length

36 mmPole Length

1.9 m

Pole Length

0.94 mPole Gap

15 - 40mm

Pole Gap

15 - 40 mm

Deflection Parameter2.00 - 0.24

Deflection Parameter

1.78 - 0.19

BL5U Helical Undulator / Optical Klystron

BL7U Apple-II variable polarization undulator

Number of Periods

21 / 9+9(Opt. Kly.)

Number of Periods

40

Period Length

110mm

Period Length

76mm

Pole Length

2.35 mPole Length

3.04 mPole Gap

30 - 150 mm

Pole Gap

24 - 200 mm

Deflection Parameter

4.6 - 0.07(Helical)

Deflection Parameter

5.4 (max. horizontal)

8.5 - 0.15(Linear)

3.6 (max. vertical)
3.0 (max. helical)

Bending Magnets
Bending Radius

2.2 m

Critical Energy

425 eV17

Beamlines in 2007
Eiji SHIGEMASAUVSOR Facility, Institute for Molecular Science
Since the successful accomplishment of the upgrade project on the UVSOR storage ring(UVSOR-II project), in which the creation of four new straight sections and the achievement of muchsmaller emittance (27 nm-rad) were planned, the UVSOR facility has become one of the highest
brilliance extreme-ultraviolet radiation sources among synchrotron radiation facilities with electronenergy less than 1 GeV. Eight bending magnets and three insertion devices are available for utilizing
synchrotron radiation at UVSOR. There is a total of fourteen operational beamlines in 2007, which
are classified into two categories. Nine of them are so-called "Open beamlines", which are open toscientists of universities and research institutes belonging to the government, public organizations,private enterprises and those of foreign countries. The rest of the five beamlines are so-called"In-house beamlines", and are dedicated to the use of research groups within IMS. We have one soft
X-rays station equipped with a double-crystal monochromator, seven extreme ultraviolet and soft
X-rays stations with a grazing incidence monochromator, three vacuum ultraviolet stations with anormal incidence monochromator, one infrared (IR) station equipped with Fourier-Transform
interferometers, one station with a multi-layer monochromator, and one non-monochromatized station
for irradiation of white-light, as shown in the appended table for all available beamlines at UVSOR.
Keeping pace with the upgrade project, the improvements and upgrades of the beamlines at
UVSOR have been continuously discussed with users in a series of UVSOR workshops. Newly
constructed (BL3U) as well as upgraded (BL5U and BL6B) beamlines synchronized with the
UVSOR-II project have routinely been operated, and a number of outcome has emerged through theutilization of these beamlines.
Concerning the utilization for the long straight section between B06
and B07, a UVSOR workshop has been held in March 2005. A high resolution and high flux
variable polarization beamline for spectroscopy in the VUV range has been proposed and possible
scientific cases performed on this beamline have been discussed there. The construction of the newbeamline BL7U has been completed during the regular summer shutdown in 2006 as planned. BL7U
is composed of a modified Wadsworth-type monochromator with three interchangeable sphericalgratings (R=10 m; 1200, 2400, and 3600 lines/mm), and a hemispherical photoelectron analyzer (MBS
‘Peter’ A-1), where high-resolution angle-resolved photoemission experiments can be performed. A
new APPLE-II type undulator for the light source of BL7U has successfully been installed at the endof October 2006. Practical utilization by users at BL7U has begun, including a sort of performance
tests for the experimental system by highly active and internationally appreciated users.
Regarding the utilization of the first in-vacuum type undulator, which has been relocated from thelong straight section U7 to the short one between B05 and B06, a new project for constructing theundulator beamline BL6U has been initiated. BL6U will be initially prepared as an in-housebeamline. The monochromator designed covers the photon energy ranging from 30 to 500 eV, withthe resolving power higher than 10000 and the photon flux more than 1010 photons/sec. The practicalconstruction of BL6U is expected to start from the summer of 2008. After the beamline
commissioning of BL6U, BL4B will be allocated to an open beamline, and all users’ activities
continued at BL8B1 will be accepted at BL4B. Further serious discussion toward utilizing the18

available straight sections most effectively and formulating a basic plan on the beamline construction,
will be continued.
All users are required to refer to the beamline manuals and the UVSOR guidebook (the latest
revision in PDF format was uploaded on the UVSOR web page in the summer of 2007), on theoccasion of conducting the actual experimental procedures. Those wishing to use the open andin-house beamlines are recommended to contact the station master/supervisor and the representative,
respectively. For updated information of UVSOR, http://www.uvsor.ims.ac.jp/.

19Table I. Station masters and supervisors of open beamlines
Beamline

Station Master

Sub MasterSupervisor

1A

N. Kondo

E. Shigemasa

E. Shigemasa

1B

M. Hasumoto

S. Kimura

S. Kimura

5U

T. ItoM. Sakai

S. Kimura

5B

M. Hasumoto

E. Nakamura

E. Shigemasa

6B

S. Kimura

E. Nakamura

S. Kimura

7U

T. ItoM. Sakai

S. Kimura

7B

M. Hasumoto

S. Kimura

S. Kimura

8B1

Y. Hikosaka

E. Nakamura

E. Shigemasa

8B2

M. Tsunekawa

E. Nakamura

S. Kimura

Table II. Representatives of in-house beamlines
Beamline

Representative

Affiliation

2B

K. Mitsuke

Dep. Photo-Molecular Science

3U

N. Kosugi

Dep. Photo-Molecular Science

4A

T. Urisu

Dep. Life & Coordination-Complex
Molecular Science

4B

E. Shigemasa

UVSOR

20

2 eV 30 eV
24 eV 205 eV

60 eV

Gas, Liquid, Solid(Absorption,
800 eV Photoemission,
Photon Emission)

25 eV

1 keV

6 eV

0.1 meV

25eV
800eV

6.2 eV
1.6 eV

21

BL1A
Soft X-Ray Beamline for Photoabsorption Spectroscopy
BL1A is a soft X-ray beamline for photoabsorption spectroscopy.

The beamline is equipped with a focusing

premirror and a double crystal monochromator [1]. The monochromator serves soft X-rays in the energy region
from 585 to 4000 eV by using several kinds of single crystals such as E-Al2O3, beryl, KTP (KTiOPO4), quartz,
InSb, and Ge. The throughput spectra measured by a Si photodiode (AXUV-100, IRD Inc.) are shown in Fig. 1.
Typical energy resolution (E/'E) of the monochromator is about 1500 for beryl and InSb.

There are no

experimental setups specific of this beamline, except for a small vacuum chamber equipped with an electron
multiplier (EM) detector. Photoabsorption spectra for powdery samples are usually measured in a total electron
yield mode, with the use of the EM detector.

Photon Flux(photons/sec./100mA)[1] Hiraya at al, Rev. Sci. Instrum. 63 (1992) 1264.

4

Beta-alumina
Beryl
KTP
InSb
Ge

2
9

10 8
6
4
2
8
10 8
6
4

1000

2000

3000

4000

5000

Photon Energy(eV)Fig. 1. Throughput spectra of the double crystal

Fig. 2. A side view of BL1A.

monochromator at BL1A.

Beamline Specifications
Monochromator

Double crystal monochromator

Monochromator crystals:

E-Al2O3 (22.53 Å, 585-1609 eV), beryl (15.965 Å, 826-2271 eV),

(2d value, energy range)

KTP (10.95 Å, 1205-3310 eV), quartz (8.512 Å, 1550-4000 eV),InSb (7.481 Å, 1764-4000 eV), Ge (6.532 Å, 2094-4000 eV)Resolution

E/'E = 1500 for beryl and InSb

Experiments

Photoabsorption spectroscopy

22

BL1B
Seya-Namioka Monochromator for General Purposes
BL1B has been constructed to perform various spectroscopic investigations such as absorption, reflectivity,and luminescence in condensed matters. This beamline consists of a pre-focusing mirror, a 1-m Seya-Namioka
type monochromator, and post-focusing mirrors with different focal lengths.

Three gratings of 600, 1200, and2400 l/mm can cover the wavelength region ranging from 40 to 650 nm (hQ = 2 – 30 eV). The post mirror witha longer focal length is usually used with an LiF window to separate the vacuum condition of themonochromator from a main experimental station, which make experiments for liquids and bio-specimens
possible, while the other is mainly utilized for solid-state spectroscopy.

The output flux from thismonochromator is about 1010 photons/sec. around 200 nm with 0.1 mm slit openings. The spectral distributions
for two gratings measured by a conventional photomultiplyer are shown in Fig. 1. A second monochromator(Spex 270M) and a LN-cooled CCD detector (Princeton Inc.) are available for luminescence measurements,
together with a liquid helium-flow type cryostat. To perform time-resolved experiments, a TAC system is alsoavailable.

Fig. 1. Photocurrent at the sample position at BL1B.

Fig. 2. Photo of BL1B.
Beamline Specifications
Monochromator

1-m Seya-Namioka type

Wavelength Range

40 to 600 nm (2-30 eV)Resolution

E/¨E~1000 at 100 nm (10 eV)

Experiment

Absorption, reflection, luminescence
spectroscopy for solids

23

BL2B
Beamline for Gas Phase Photoionization and Reaction Dynamics
This beamline has been developed for the purpose of studying ionization, excitation and decay dynamics
involving inner-valence electrons, 2p electrons of the third row atoms, and 4d electrons of the lanthanides. The
monochromator is a spherical grating Dragon-type with 18-m focal length. High throughput (1 u 1010 photonss-1) and high resolution (E/'E = 2000 - 8000) are achieved simultaneously under the condition of the ring currentof 100 mA [1]. The optical system consists of two prefocusing mirrors, an entrance slit, three spherical gratings(G1 - G3), two folding mirrors, a movable exit slit and a refocusing mirror [2]. The monochromator is designed
to cover the energy range of 23 - 205 eV with the three gratings: G1 (2400 lines mm-1, R = 18 m) at 80 - 205 eV;
G2 (1200 lines mm-1, R = 18 m) at 40 - 100 eV; G3 (2400 lines mm-1, R = 9.25 m) at 23 - 50 eV. The percentageof the second-order light contamination at hQ = 45.6 eV is 23 % for G2 or 7 % for G3.
We have been taking the yield curves of various fullerene ions [3]. Geometrical structures and electronic
properties of fullerenes have attracted widespread attention because of their novel structures, novel reactivity,and novel catalytic behaviors as typical nanometer-size materials. However, spectroscopic information was very
limited in the extreme UV region, owing to difficulties in acquiring enough amount of sample. This situation has
been rapidly changed since the start of this century, because the techniques of syntheses, isolation, andpurification have been advanced so rapidly that appreciable amount of fullerenes can be readily obtained.

Fig. 1. 18-m spherical grating
monochromator at BL2B.

Fig. 2. End station of BL2B for gas phase
spectroscopy of refractory materials.

[1] M. Ono, H. Yoshida, H. Hattori, K. Mitsuke, Nucl. Instrum. Meth. Phys. Res. A 467-468 (2001) 577.
[2] H. Yoshida, K. Mitsuke, J. Synchrotron Radiat. 5 (1998) 774.
[3] J. Kou, T. Mori, Y. Kubozono, K. Mitsuke, Phys. Chem. Chem. Phys. 7 (2005) 119.
Beamline Specifications
Monochromator

18-m spherical grating Dragon-type

Wavelength Range

6 – 55 nm; 24 – 205 eVResolution

2000 – 8000 depending on the gratings

Experiment

Mass spectrom.; Photoelectron spectrosc.; Momentum imaging
spectrosc.; e--Ion coincidence spectrosc.; Fullerene beam source

24

BL3U
Varied-Line-Spacing Plane Grating Monochromatorfor Molecular Soft X-Ray Spectroscopy
The beamline BL3U is equipped with an in-vaccum undulator composed of 50 periods of 3.8 cm period length.
The emitted photons are monochromatized by the varied-line-spacing plane grating monochromator (VLS-PGM)
designed for various spectroscopic investigations in the soft x-ray range including soft x-ray emission studies.
Three holographically ruled laminar profile plane gratings are designed to cover the photon energy range from
60 eV to 800 eV. The beamline has two endstations, namely XES setup and Multi-purpose setup. The XES setup
is used for soft x-ray emission spectroscopy. The beam is horizontally focused onto the sample position byplane-elliptical mirror, M2X. In the Multi-purpose setup, the beam is focused by the toroidal mirror M2.
Between the sample position and M2, the differential pumping is placed.

Top View

XES Setup

S0

S1X
M1: Spherical G: VLSP
R=88.826 m

in-vacuum
M0: Cylindricalplane undulator R=47.253 m

sample176°

M2X: Plane-Elliptical
r1=11.7 m
r2=0.5 m
M2: Toroidal
R=81.65 m
ρ= 37.23 mm

Multi-purpose setup S1

sample

176°
700
0

5300

3100
6000

400
9100

Side View

2203

500

9500

11703

G

M2X

800
12203

13003

14603

S1X
sample

176°
177°

1600

173°

M1

S1

M0

M2

sample  Fig. 1. Schematic layout (left) and the photography (right) of the BL3U. The distances along the beam from thecenter of the in-vacuum plane undulator are shown in mm. S1X and M2X can be replaced with the other exit slit
S1 so that experiments can be carried out at either the XES or multi-purpose endstation. In the XES setup, thesample is placed at 5-10 mm downstream of S1X.

Beamline Specifications
Monochromator

Varied-line-spacing plane grating monochromator

Energy Range

60-800 eVResolution

E/'E > 10 000

Experiment

Soft X-ray spectroscopy (XPS, XES, XAS)

Beam Size

Gaussian shape(XES Endstation)

Vertical 5-20 Pm; Horizontal 41 Pm (FWHM)

25

BL4A
Multilayered Mirror Monochromator for Photochemistry
BL4A1 has been constructed to perform the synchrotron radiation induced etching of Si and SiO2 using XeF2
as an etching gas. This beam-line is composed of a multilayered mirror (MLM) monochromator, a beam
condenser system, and a differential pump system. The XeF2 pressure during the etching will reach to 0.5 Torr,so a differential pump apparatus is installed in the vacuum system and the etching chamber as shown in Fig. 1.
The etching chamber is evacuated independently and is designed to achieve high pressure (0.5 Torr) keeping
other vacuum system at low pressure (< 10-5 Torr) by an aperture flange and a sequence of pressure stages. The
condenser mirror focuses the divergent radiation onto the sample surface in the etching chamber, and obtains an
extreme higher photon flux can be obtained.

Fig. 1. Section view of differential pump apparatus installed in
the etching chamber (reaction cell) and the entrance of beam.

Fig. 2. A side view of the end-station at BL4A1.

Beamline Specifications
Monochromator

Multilayered mirror monochromator

Wavelength Range

13.3 ~ 22.5 nm

Resolution

5 ~ 9 eV (FWHM)

Experiment

Irradiation

Miscellaneous

Not-in-use for SR users

26

BL4B
Varied-Line-Spacing Plane Grating Monochromatorfor Molecular Soft X-Ray Spectroscopy
The beamline BL4B equipped with a varied-line-spacing plane grating monochromator (VLS-PGM) wasconstructed for various spectroscopic investigations in a gas phase and/or on solids in the soft X-ray range.
Three holographically ruled laminar profile plane gratings with SiO2 substrates are designed to cover the photon
energy range from 25 eV to 800 eV.

The gratings with the groove densities of 100, 267, and 800 l/mm cover

the spectral ranges of 25-100, 60-300, and 200-1000 eV, respectively, and are interchangeable without breaking
the vacuum.

Fig. 1 shows the absolute photon flux for each grating measured by a Si photodiode (IRD Inc.),with the entrance- and exit-slit openings set at 50 and 50 Pm, respectively.

The maximum resolving power(E/'E) achieved for each grating is more than 5000.

㻌
㻝㻱㻝㻞

㻝㻱㻝㻝

㻿㼘㼕㼠㻦㻌㻡㻜P㼙㻙㻡㻜P㼙

㻳㻞

㻝㻱㻝㻜

㻌

㻵㼚㼠㼑㼚㼟㼕㼠㼥㻌㻔㼜㼔㼛㼠㼛㼚㼟㻛㼟㻕

㻳㻟

㻳㻝
㻝㻱㻥

㻝㻱㻤
㻜

㻞㻜㻜

㻠㻜㻜

㻢㻜㻜

㻤㻜㻜

㻝㻜㻜㻜

㻝㻞㻜㻜

㻼㼔㼛㼠㼛㼚㻌㻱㼚㼑㼞㼓㼥㻌㻔㼑㼂㻕

Fig. 1. Throughput from the VLS-PGM monochromator on

Fig. 2. Photo of BL4B.

BL4B.

Beamline Specifications
Monochromator

Varied-line-spacing Plane Grating Monochromator

Energy range

25-1000 eVResolution

E/'E ! 5000 (at maximum)

Experiments

Soft X-ray spectroscopy (mainly, angle-resolved photoion spectroscopy forgaseous targets and photoelectron spectroscopy for gaseous and solid targets)

27

BL5U
Photoemission Spectroscopy of Solids and Surfaces
This beamline is designed for a high-resolution angle-resolved photoemission study on solids and surfaces
with horizontal-linearly and circularly (CW, CCW) polarized synchrotron radiation from a helical undulator.
The beamline consists of a Spherical Grating Monochromator with Translational and Rotational Assembly
Including a Normal incidence mount (SGM-TRAIN), and a high-resolution angle-resolved photoemission
spectrometer.
The SGM-TRAIN is an improved version of a constant-length SGM to aim the following points; (1) covering
the wide energy range of 5-250 eV, (2) high energy resolving power, (3) use of linearly and circularly polarized
undulator light, (4) reduction of higher order light, and (5) two driving modes (rotation and translation ofgratings) by computer control.

The second-order light is well suppressed by using laminar profile gratings andombinations of mirrors and gratings.

Fig. 1. Throughput spectra from the SGM-TRAIN monochromator at BL5U.
Beamline Specifications
Monochromator
Energy Range
Resolution
Experiment
Flux

SGM-TRAIN
5-250 eV

Main Instruments

Hemisphericalphotoelectron
analyzer (MBS-Toyama ‘Peter’A-1), LEED of reverse type
(OMICRON), Liq-He flow cryostat(5 – 400 K)

hQ/'E >2,000 for < 40Pm slits
ARPES, AIPES, XAS<1011 photons/s for < 40Pm slits (atthe sample position)

Fig.

2.

High-resolution

angle-resolved

photoemission apparatus at BL5U.

28

BL5B
Calibration Apparatus for Optical Elements and Detectors
BL5B has been constructed to perform calibration measurements for optical elements and detectors.
beamline is composed of a plane grating monochromator (PGM) and three end stations in tandem.

ThisThe most

upstream station is used for calibration measurements of optical elements, the middle one for opticalmeasurements for solids and the last for photo-stimulated desorption experiments.

The experimental chamberat the most downstream station is sometimes changed to a chamber for photoemission spectroscopy.
The calibration chamber shown in Fig. 2 is equipped with a goniometer for the characterization of opticalelements, which has six-degree-of-freedom; X-Y translation of a sample, and interchange of samples and filters.
These are driven by pulse motors in vacuum.

Since the polarization of synchrotron radiation is essential forsuch measurements, the rotation axis can be made in either horizontal or vertical direction (s- or p-polarization).

G1M0
G1M1
G1M2
G2M1
G2M2
G2M3
G2M4
G3M3
G3M4
G3M5
G3M6

Photocurrent (A)

10 -9

10

-10

10

-11

1

2

3

4

5

6

7 8 9

10

2

3

4

Wavelength (nm)

5

6

7 8 9

100

2

Fig. 2. A side view of the experimental chamber
for calibration measurements.

Fig. 1. Throughput spectra for possible combinations ofgratings and mirrors at BL5B measured by a gold mesh.

Beamline Specifications
Monochromator

Plane Grating Monochromator

Energy range

6-600 eV (2-200 nm)

Resolution

E/'E a 500

Experiments

Calibration of optical elements, absorption of solids, photo-stimulated
desorption from rare gas solids

29

BL6B
Infrared and Terahertz Spectroscopy of Solids
SR has a good performance (high brilliance and high flux) not only in VUV and SX regions but also in IR andterahertz regions. This beamline covers in the IR and terahertz regions.

The previous beamline BL6A1 thathas been constructed in 1985 is the pioneer of the infrared SR research. The beamline was upgraded in thespring of 2004 and the name was changed to be BL6B (IR).

The front-end part including the bending duct #6

was replaced to a new one with higher acceptance angle using a magic mirror as shown in Fig. 1.
The beamline is equipped with two interferometers, one is Michelson-type (Bruker IFS-66v) and the otherMartin-Puplett-type (JASCO FARIS-1), for the wide spectral region from several to 20,000 cm-1 (hQ = several
100 PeV – 2.5 eV) as shown in Fig. 2. The experimental chamber in which users bring can be equipped at thefree port. In the near future, an IR microscope covering down to terahertz region will be set up.

Magic mirror
B6
BL6U
First focusing
point
Martin-Puplett
FT-FIR

Radiation
shieldMichelson
FT-IR
Free
port

Fig. 1. The design of optics and front end of
BL6B.

Interferometer
Wavenumber Range(Energy range)
Resolution in cm-1
Experiments
MiscellaneousFig. 2. Schematic figure of top view of BL6B.

Beamline Specifications
Michelson (Bruker IFS66v),
Martin-Puplett (JASCO FARIS-1)
several – 20,000 cm-1
(several 100 PeV – 2.5 eV)
0.1cm-1 for IFS66v
0.25cm-1 for FARIS-1
Reflectivity and transmission
Magneto-optics(Microspectroscopy)
Users can bring their experimental system inthis beamline.

30

IR microscope(planned)

BL7U
Angle-Resolved Photoemission of Solids in the VUV Region
The beamline 7U is constructed to provide the photon flux with high energy resolution and high flux mainly
for high-resolution angle-resolved photoemission spectroscopy of solids. An APPLE-II-type variable
polarization undulator is equipped for the light source. The undulator can make high intense VUV light withhorizontal/vertical linear and right/left circular polarization. The undulator light is monochromatized by themodified Wadsworth-type monochromator with three gratings (R = 10 m; 1200, 2400 and 3600 lines/mm
optimized at hQ = 10, 20, and 33 eV). The energy resolution of light (hQ/'hQ) is more than 104 with the photon
flux of more than 1011 a 1012 ph/s on samples in the whole energy region.
The beamline has a photoemission end station which equips a 200-mm-radius hemispherical photoelectron
analyzer (MB Scientific AB, A-l analyzer) and a liquid-helium-cooled cryostat with a 6-axes pulse motor control(A-VC Co. Ltd., i-GONIO). The main purpose is to determine the three-dimensional Fermi surface andelectronic structure of solids at low temperatures and their temperature dependence to reveal the origin of thephysical properties.

Fig.1. Schematic figure of BL7U.

Beamline Specifications
Light source
Monochromator
Photon energy range
Resolution (hQ/' hQ)
Photon flux on sample
Beam size on sample
Experiments

APPLE-II type undulator (Ou = 76mm, N = 36)
10-m Normal Incidence Monochromator(modified Wadsworth-type)6 a 40 eV (O = 30 a 200 nm)
1u104 a5u104
t1012 a 1011 ph/s (depend on hQ)
200(H)u50(V) Pm2
Angle-resolved photoemission of solids(MB Scientific A-1 analyzer)

31

BL7B
3-m Normal Incidence Monochromator for Solid-State Spectroscopy
BL7B has been constructed to provide sufficiently high resolution for conventional solid-state spectroscopy,
enough intensity for luminescence measurements, a wide wavelength coverage for Kramers-Kronig analyses,
and the minimum deformation to the polarization characteristic of the incident synchrotron radiation.

Thisbeamline consists of a 3-m normal incidence monochromator which covers the vacuum ultraviolet, ultraviolet,
visible and infrared, i.e. the wavelength region of 40 -1000 nm, with three gratings (1200, 600, and 300 l/mm).
Two interchangeable refocusing mirrors provide two different focusing positions.

For the mirror with thelonger focal length, an LiF or a MgF2 window valve can be installed in between the end valve of the beamline
and the focusing position. Figure 1 shows absolute photon intensity for each grating with the entrance and exit
slit openings of 0.5 mm.

A silicon photodiode (AXUV-100, IRD Inc.) was utilized for measuring the photon

intensity and the absolute photon flux was estimated, taking the quantum efficiency of the photodiode into
account.

Fig. 2. Photo of BL7B.

Fig. 1. Throughput spectra of BL7B measured by asilicon photodiode.

Beamline Specifications
Monochromator

3-m Normal Incidence Monochromator

Wavelength Range

50 to 1000 nm (1.2 - 25 eV)Resolution

E/'E = 4000 8000 for 0.01 mm slits

Experimentabsorption, reflection, fluorescence
spectroscopy, mainly for solids

32

BL8B1
Spherical Grating Monochromator for Soft X-Ray Spectroscopic
Studies on Solids and Surfaces
The beamline BL8B1 equipped with a constant-deviation constant-length spherical grating monochromator[1] provides soft X-ray photons in the energy range 30-800 eV with medium energy resolution.

The photon

energy range is covered by using three gratings (R=15 m; 1080 l/mm, R=15 m; 540l/m, and R=7.5m; 360 l/mm)
which are interchangeable in vacuum.
exit-slit openings of 10 Pm.

Figure 1 shows a throughput spectrum measured with the entrance- andUnder this condition, the achievable resolving power is about 4000 at 400 eV and3000 at 245 eV, respectively.
An experimental chamber is equipped for conventional measurements of electron yield spectra, or
pseudo-photoabsorption spectra, under a ~1×10-6 Torr vacuum condition.
[1] Hiraya et al., Rev. Sci. Instrum. 66 (1995) 2104.

Flux (Photons/sec./100mA)

1010

Slits: 10 μm

G3: 360 l/mm

910

G2: 540 l/mm
8

10

107

G1: 1080 l/mm
6

10

0

200

400
600
800
Photon Energy (eV)1000

Fig. 2. Throughput of the monochromator at BL8B1.

Fig. 1. Photo of BL8B1.

Beamline Specifications
Monochromator

Constant-deviation constant-length spherical grating type

Energy range

30-800 eVResolution

E/'E = 4000 at 400 eV and 3000 at 245 eVExperiments

Photoabsorption

spectroscopy,

electron

spectroscopy

coincidence spectroscopy for solids and surfaces

33

and

electron-ion

BL8B2
Angle-Resolved Ultraviolet Photoelectron Spectrometer for Solids
BL8B2 is a beamline for angle-resolved ultraviolet photoemission spectroscopy (ARUPS) system which isdesigned for measuring various organic solids such as molecular crystals, organic semiconductors, andconducting polymers. This beamline consists of a plane-grating monochromator (PGM), a sample preparationchamber with a fast entry Load-Lock chamber, a measurement chamber with an accurate for temperaturedependence (base pressure 1×10-10Torr), a cleaning chamber (base pressure 1×10-10Torr), and a sample
evaporation chamber (base pressure 3×10-10Torr). The cleaning chamber is equipped with a back-view
LEED/AUGER, an ion gun for Ar+ sputtering, and an infrared heating unit. The PGM consists of premirrors, aplane grating, focusing mirror, and a post-mirror, with an exit slit. It covers the wide range from 2 to 130eV withexchanging two gratings (G1: 1200l/mm, G2: 450l/mm) and five cylindrical mirrors. The toroidal mirror focuses
the divergent radiation onto the sample in the measurement chamber. The spot size of the zeroth-order visible
light at the sample surface is about 1×1mm2. Figure 1 shows the throughput spectra of PGM (slit=100ȝm). Theenergy resolution at a slit width of 100ȝm was found to be E/ǻE = 1000 in the wavelength range from 2 to130eV. A hemi-spherical electron energy analyzer of 75mm mean radius with an angular resolution less than 2°
can be rotated around vertical and horizontal axes. The sample mounted on a manipulator can be also rotatedaround two axes.

Sample Current / A / R.C(100mA=1)

1E-8

1E-9

1E-10

GM[24]
GM[13]
GM[12]
GM[11]

1E-11

1E-12

0

20

40

60

80

100 120 140

Photon Energy / eV

Fig. 2. A photo of BL8B2.

Fig. 1. Throughput spectra of plane-grating
monochromator at BL8B2 (slit=100ȝm).
Beamline Specifications
Monochromator

Plane-grating monochromator

Wavelength Range

9- 600nm

Resolution

E/ǻE = 1000

Experiment

Angle-resolved ultraviolet photoemission spectroscopy

34