Ⅱ

Current Status ofLight Sources andBeamlinesⅡ . Current Status of Light Sources and Beamlines

Light Source in 2018
1. Status of UVSOR Accelerators

former case, it took about several days to completely
repair the power supply. In the latter, the chilling
water unit was malfunctioned. We gave up to use it
and alternatively we started supplying the chilling
water to the linac from the cooling water system forother part of accelerator system. It has been working
well without any trouble.
In February 2018, a cooling water leakage wasfound at a sextupole coil wound on a pole face of amultipole (quadrupole/sextupole) magnet. After about
one year, we have found similar leakage on nine ofsame coils. The hollow conductor used for these coils
has relatively thin wall. It is supposed that, after the
installation in 2003, the walls have been eroded by
the water flow. In the spring shutdown 2019, we areapplying liquid sealant for all the coils for life
prolonging. In parallel, we have started constructing
coils for replacement.

In the fiscal year 2018, we had scheduled to operate
UVSOR-III from May to March, for 36 weeks forusers. We had several machine troubles as describedlater. In July we had a trouble in the linac and we
could not operate the machine in the top-up mode
almost for one week, in adding to 12 hour loss. In
cases of other minor troubles, we extended theoperation time for compensation. We had a scheduled
shutdown period in April and May for about 6 weeks.
This was mainly for the scheduled maintenanceworks. We had one week shut down period in Augustand October, two week one around the New Years
day and one week one at the end of March. We had 2
weeks for machine and beamline conditioning in May
after the spring shut down. In addition, we had 4
weeks for machine conditionings and studies, in
October, November, January and March. The
machine study week in November was mainly for themachine conditioning after the annual planned power
outage.
We operated the machine for 34 weeks in themulti-bunch top-up mode at 300 mA, and 2 weeks inthe single-bunch top-up mode at approximately 40
mA. The monthly statistics of the operation time andthe integrated beam current are shown in Fig. 1.

Fig. 2. The sextupole main coil wound on the poleface of a quadrupole magnet.
2. Improvements and Developments
In the UVSOR accelerator system, there are stillsome components which have been used since theconstruction of the facility early in 1980’s. This year,
after more than 35 year operation, the pulse
transformer for the klystron modulator of the linac
was replaced (Fig. 3). The cooling water system for
the RF cavity in the booster synchrotron was also
replaced with the one which has a good temporalstability of 0.1 degree C. The control system of theundulator U6 was replaced after 15 year operation.
The signal generator as the master oscillator of theaccelerator complex was also replaced this year.
The chilling water system for the linac had troubles
several times in the past, which were mainly due tothe unstable cooling water supply from the facility.
This system provided 20 degree chilling water to thetemperature control system of the linac. We tried touse about 25 degree water from the facility instead ofFig. 1. Monthly statistics in FY2018.
The weekly operation schedule is as follows. On
Monday, from 9 am to 9 pm, the machine is operated
for machine conditionings and studies. On Tuesday andWednesday, from 9am to 9pm, the machine is operated
for users. From Thursday 9am to Friday 9pm, themachine is operated for 36 hours continuously forusers. Therefore, the beam time for users in a week is
60 hours. In the single bunch operation weeks, themachine is operated for 12 hours per day from Tuesday
to Friday.
We had a trouble in the high voltage power supplies
and the cooling water system for the linac in July. The

99Ⅱ

Ⅱ . Current Status of Light Sources and Beamlines

the 20 degree chilling water and found that the linac
could be operated stably without any problem. We
stopped using the chilling water system.

Light Source Developments and Beam Physics
Studies
We continue the efforts to develop novel lightsources technologies and their applications such as
free electron lasers, coherent harmonic generation,
coherent synchrotron radiation, laser Compton
scattering gamma-rays, intense polarized and vortex
UV radiation at the source development station BL1U,
which was constructed under the support of Quantum
Beam Technology Program by MEXT/JST. In theseyears, we continued studying the generations ofstructured light beam from undulators incollaboration with Hiroshima U., Nagoya U. andother institutes. Since the UVSOR electron beam isdiffraction-limited in the UV range, we could
precisely investigate the optical properties of thevortex beams from undulators using conventional
optical components. Moreover, we succeeded in
producing optical vector beam which has a tailored
distribution of the polarization in the transverse plane.
The laser Compton scattering gamma-rays are
powerful tools for nuclear science and technologies.
By using various external lasers, we havedemonstrated
generating
quasi-monochromatic
gamma-rays in the energy range from 1MeV toaround 10MeV. We continue the experiments incollaboration with Kyoto U., AIST and QST towards
imaging applications. We started new experiments on
positron lifetime spectroscopy experiments incollaboration with Yamagata U., Nagoya U. and
AIST.

Ⅱ

Fig. 3 New pulse transformer for the klystron
modulator of the linac.

Masahiro KATOH(UVSOR Synchrotron Facility)

Fig. 4. New Control system for the undulator U6

10
10

Ⅱ . Current Status of Light Sources and Beamlines

UVSOR Accelerator Complex
Injection Linear Accelerator

Booster Synchrotron

EnergyLengthFrequency
Accelerating RF Field
Klystron Power
Energy Spread
Repetition Rate

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

15 MeV
2.5 m
2856 MHz
2π/3 Traveling Wave
1.8 MW~1.6 MeV
2.6 HzUVSOR-III Storage-Ring
Energy750 MeV
Injection Energy
750 MeV
Maximum Storage Current 500 mA (multi bunch)
100 mA (single bunch)Normal operation current 300 mA (multi bunch)(Top-up mode)
50 mA (single bunch)
Natural Emittance
17.5 nm-rad
Circumference
53.2 mRF Frequency
90.1 MHz
Harmonic Number
16
Bending Radius
2.2 m
Lattice
Extended DBA×4
Straight Section(4 m×4)+(1.5 m×4)
RF Voltage
120 kV
Betatron Tune
3.75
Horizontal
3.20
VerticalMomentum Compaction 0.030
Natural Chromaticity-8.1
Horizontal-7.3
Vertical
Energy Spread
5.26×10-4
Coupling Ratio
1%
Natural Bunch Length
128 ps

750 MeV
15 MeV
32 mA (uniform filling)
26.6 m90.1 MHz
8
1.8m
FODO×815 MeV
Linear
Accelerator
750 MeV
Booster
Synchrotron

2.25
1.25
0.138
1 Hz (750 MeV)

BL5B

BL5U

BL6U
BL6B

BL1U
BL7U

BL4B

3rd
Harmonic cavity
Main Cavity

BL7B

BL4U

750 MeVElectron
Storage Ring

BL3B

BL3U
BL1U

BL2B

BL1B
BL2A

Electron Beam Optics of UVSOR-III Storage Ring

Horizontal/verticalelectron beam sizeand beam divergences

σx,y [mm]σ'x,y [mrad]ηx√βx,y [√m]

Horizontal/verticalbetatron functions
and dispersion function

Position [m]Position [m]11ⅡⅡ . Current Status of Light Sources and Beamlines

Insertion Device

Ⅱ

Brilliance of radiationfrom the insertion devices(U3, U4, U5, U6 and U7)
and a bending magnet
of UVSOR-III

U5 Apple-II
Variable Polarization Undulator
Number of Periods
38
Period length
60 mm
Pole Length2.28 mPole Gap
24-190 mm
Deflection Parameter
3.4 (Max. Horizontal)
2.1 (Max. Vertical)
1.8 (Max. Helical)

U1 Apple-II Undulator /Optical Klystron
Number of Periods
Period length
Pole Length
Pole Gap
Deflection Parameter

10+10
88 mm
0.968 m + 0.968 m
24-200 mm
7.36 (Max.
Horizontal)
4.93 (Max. Vertical)
4.06 (Max. Herical)

U6 In-vacuum Undulator
Number of Periods
Period length
Pole Length
Pole Gap
Deflection ParameterU3 In-vacuum Undulator
Number of Periods
Period length
Pole Length
Pole Gap
Deflection Parameter

50
38 mm
1.9 m
16.5-40 mm
1.8-0.24

U7 Apple-II
Variable Polarization Undulator
Number of Periods
40
Period length
76 mmPole Length
3.04 mPole Gap
24-200 mm
Deflection Parameter
5.4 (Max. Horizontal)
3.6 (Max. Vertical)
3.0 (Max. Helical)

U4 In-vacuum Undulator
Number of Periods
Period length
Pole Length
Pole Gap
Deflection Parameter

26
36 mm
0.94 m13-40 mm
1.78 - 0.19

26
38 mm
0.99 m13-40 mm2.4-0.19

Bending Magnets
Bending Radius
Critical Energy

12

2.2 m
425 eVⅡ . Current Status of Light Sources and Beamlines

Beamlines in 2018
Kiyohisa TANAKAUVSOR synchrotron Facility, Institute for Molecular Science
Ⅱ
Among the synchrotron radiation facilities withelectron energies of less than 1 GeV, UVSOR is oneof the highest-brilliance light sources in theextreme-ultraviolet region. The natural emittance of
the UVSOR-III storage ring is as low as 17.5 nm-rad
after the successful completion of the storage ring
upgrade project (the UVSOR-III project) in 2012.
Eight bending magnets and six insertion devices
are available as synchrotron light sources at UVSOR.
As of 2017 there are a total of fourteen operational
beamlines, which are classified into two categories.
Twelve of them are the so-called “Open beamlines”,
which are open to scientists from universities andresearch institutes belonging to the government,
public organizations, private enterprises and also
those from foreign countries. The remaining two
beamlines are the “In-house beamlines”, and are
dedicated to the use of research groups within
Institute for Molecular Science (IMS).
There is one soft X-ray station equipped with adouble-crystal monochromator, seven extreme
ultraviolet and soft X-ray stations with grazing
incidence monochromators, three vacuum ultraviolet(VUV)
stationswithnormalincidence
monochromators, two infrared (IR) stations equippedwith Fourier-Transform interferometers, and one
direct radiation station located after two undulators
installed in tandem, as shown in the appended table(next page) for all available beamlines at UVSOR in
2018. The details of the updates for several beamlines
are the followings.
BL1U, which is one of the in-house beamlines, hasbeen partially open for general users from Oct. 2018.
Users can use UV/VUV light and gamma rays forirradiation experiments.
In BL3B, a new sample stage has been developed.
Samples can be heated up to ~500 K during the
VIS-VUV photoluminescence and reflection/
absorption spectroscopy measurements.
BL5U has been officially opened for users from2016 as high energy resolution angle-resolved
photoemission spectroscopy (ARPES) beamline.
Using a new mirror located close to the sample

position, the beam spot size is successfully focused to~23 x 40 μm, which make users possible to performmeasurements on small samples or inhomogeneous
samples. A new software to precisely control thesample position has been developed, and users caneasily take intensity image from sample with 10 μm
step and move to some particular position of thesample in the obtained image.
In BL6U, which is one of the in-house beamlines,
the latest version of ARPES analyzer was installed(MB Scientific AB, A-1 analyzer Lens#5).
Manipulator was modified so that a mesh can be set
in front of the sample and the sample can be biased
voltages. By applying bias voltages to the sample, thewider acceptance angle (~ 60 deg.) with hν = 40-60
eV is available. We also have performed in situ
cleaning of mirrors by exposure to oxygen at apressure of 1x10-2 Pa under irradiation of
non-monochromated synchrotron radiation (SR). As aresult, the photon intensity around 280 eV has greatly
been improved.
In BL7U, a high energy resolution ARPES
beamline with low energy of photons, a new low
temperature 6-axis manipulator was developed andinstalled from FY2018. Samples can be cooled down
to 4.5 K with tilt angle -15 ~ 50 deg. and azimuth
angle ± 120 deg..
UVSOR is now planning to introduce so-called“Momentum microscope (MM)”, which is anelectronic spectroscopy with both the real space andmomentum space resolution. The original plan has
been modified and MM will be installed at BL6U.
Tender process for MM analyzer has been concluded
and it will be installed in FY2019.
All users are required to refer to the beamline
manuals and the UVSOR guidebook (the latest
revision in PDF format uploaded on the UVSOR web
site in June 2018), on the occasion of conducting theactual experimental procedures. Those wishing to
use the open and in-house beamlines arerecommended to contact the appropriate beamline
master (see next page). For updated information on
UVSOR, please see http://www.uvsor.ims.ac.jp.

13
13

Beamlines at UVSOR
Ⅱ

Beamline

Monochromator /Spectrometer

BL1U

Free electron laser

BL1B

Martin-Puplett FT-FIR

BL2A

Double crystal

BL2B

18-m spherical grating(Dragon)

BL3U

Varied-line-spacing
plane grating(Monk-Gillieson)

BL3B

2.5-m off-plane Eagle
Varied-line-spacing
plane grating(Monk-Gillieson)
Varied-line-spacing
plane grating(Monk-Gillieson)

BL4U
BL4B
BL5U

Spherical grating(SGM-TRAIN†)

BL5B

Plane grating

BL6U*

Variable-included-angle
varied-line-spacing
plane grating

BL6B

Michelson FT-IR

BL7U

10-m normal incidence(modified Wadsworth)BL7B

3-m normal incidence

Energy Range

Targets

585 – 4 keV
23 – 205 eV
40 – 800 eV
1.7 – 31 eV
50 – 770 eV
25 eV – 1 keV
20 – 200 eV
6 – 600 eV
45 – 600 eV
4 meV – 2.5 eV
6 – 40 eV
1.2 – 25 eV

Yellow columns represent undulator beamlines.
In-house beamline.

*

14
14

Contact(Irradiation)

M. Fujimoto

Solid

Reflection
Absorption

K. Tanaka

Solid

Reflection
Absorption

K. Tanaka

Solid

Photoemission

S. KeraGas
LiquidSolid

Absorption
Photoemission
Photon-emission
Reflection
Absorption
Photon-emission

1.6 – 13.9 eV
0.5 – 30 meVTechniquesSolidmfmoto@ims.ac.jp

k-tanaka@ims.ac.jp

k-tanaka@ims.ac.jp

kera@ims.ac.jp

M. Nagasaka

nagasaka@ims.ac.jp

K. Tanaka

k-tanaka@ims.ac.jp

Gas
LiquidSolid

Absorption(Microscopy)

T. Ohigashi

Gas
Solid

Photoionization
Photodissociation
Photoemission

H. Iwayama

Solid

Photoemission

K. Tanaka

Solid

Calibration
Absorption

K. Tanaka

Gas
Solid
Solid

Photoionization
Photodissociation
Photoemission
Reflection
Absorption
IR microscopeohigashi@ims.ac.jp

iwayama@ims.ac.jp

k-tanaka@ims.ac.jp

k-tanaka@ims.ac.jp

F. Matsui

matui@ims.ac.jp

K. Tanaka

k-tanaka@ims.ac.jp

Solid

Photoemission

S. Ideta

Solid

Reflection
Absorption
Photon-emission

K. Tanaka

idetas@ims.ac.jp

k-tanaka@ims.ac.jp

BL1U

Light Source Development Station
Ⅱ▼Description
BL1U is dedicated for developments and applications of various novel photon sources including free electron
laser in the range from visible to deep UV, coherent harmonic generation in the deep UV and VUV, laser
Compton scattering gamma-rays and undulator radiation with various polarization properties including opticalvortex beam and optical vector beam.
The beam-line is equipped with a dedicated twin polarization variable undulator system with a buncher section,
which can be used for a FEL oscillator and a VUV CHG. It is also equipped with a femto-second laser system
synchronized with the accelerator, which is used for CHG, slicing, LCS and coherent THz radiation generation.

Fig. 1. Configuration of the free electron laser (under reconstruction)

Fig. 2. Twin Apple-II Undulator

Fig. 3. Accelerator synchronized Laser System▼Technical Data of FEL▼Technical Data of Ti:Sa Laser

Wave Length

199-800 nm

Wave Length

800 nmSpectral Band Width~10

Pulse Length

130 fsec

Polarization

Circular/Linear

Oscillator

90.1 MHz

Pulse Rate

11.26 MHz

Pulse Energy

2.5mJ

10mJ

50mJ

Max. Ave. Power~1W

Repetition Rate

1kHz

1kHz

10Hz

-4

15
15

BL1B

Terahertz Spectroscopy Using Coherent Synchrotron Radiation
Ⅱ▼Description
Coherent synchrotron radiation (CSR) is a powerful light source in the terahertz (THz) region. This beamline
has been constructed for basic studies on the properties of THz-CSR. However, it can be also used formeasurements of reflectivity and transmission spectra of solids using conventional synchrotron radiation.
The emitted THz light is collected by a three-dimensional magic mirror (3D-MM, M0) of the same type as
those already successfully installed at BL43IR in SPring-8 and BL6B in UVSOR-II. The 3D-MM was installed
in bending-magnet chamber #1 and is controlled by a 5-axis pulse motor stage (x, z translation; x, y, zrotation). The acceptance angle was set at 17.5-34 degrees (total 288 mrad) in the horizontal direction. The
vertical angle was set at 40 mrad to collect the widely expanded THz-CSR.
The beamline is equipped with a Martin-Puplett type interferometer (JASCO FARIS-1) to cover the THz
spectral region from 4 to 240 cm-1 (h = 500 eV-30 meV). There is a reflection/absorption spectroscopy (RAS)
end-station for large samples ( several mm). At the RAS end-station, a liquid-helium-flow type cryostat with aminimum temperature of 4 K is installed.

Fig. 1. Schematic top view of the beam extraction part of
the THz-CSR beamline, BL1B. The three-dimensional
magic mirror (3D-MM, M0) and a plane mirror (M1) arelocated in the bending-magnet chamber. A parabolic mirror(M2) is installed to form a parallel beam. The straightsection (BL1U) is used for coherent harmonic generation(CHG) in the VUV region.

Fig. 2. Obtained intensity spectra with the
combination of a light source (UVSOR),
interferometer (FARIS-1), and detectors (Sibolometer and InSb hot-electron bolometer).

▼Technical Data
Interferometer

Martin-Puplett (JASCO FARIS-1)

Wavenumber range(Energy range)

4-240 cm-1
(500 eV-30 meV)

Resolution in cm-1

0.25 cm-1

Experiments

Reflection/transmission spectroscopy

Miscellaneous

Users can use their experimental system in this beamline.

16
16

BL2A

Soft X-Ray Beamline for Photoabsorption Spectroscopy
Ⅱ▼Description
BL2A, which was moved its previous location as BL1A in 2011, 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 using several types of single
crystals, such as β-Al2O3, beryl, KTP (KTiOPO4), quartz, InSb, and Ge. The throughput spectra measured usinga Si photodiode (AXUV-100, IRD Inc.) are shown in Fig. 1. The typical energy resolution (E / ΔE) of themonochromator is approximately 1500 for beryl and InSb.
A small vacuum chamber equipped with an electron multiplier (EM) detector is available. Photoabsorption
spectra for powdery samples are usually measured in total electron yield mode, with the use of the EM detector.
A silicon drift detector is also available for measuring partial fluorescence yields from solid samples.
[1] Hiraya et al., Rev. Sci. Instrum. 63 (1992) 1264.

Fig. 1. Throughput spectra of the double-crystal
monochromator at BL2A.

▼Technical Data

Monochromator
Monochromator crystals:(2d value, energy range)
Resolution
Experiments

Fig. 2. Side view of BL2A.

Double crystal monochromator
β-Al2O3 (22.53 Å, 585–1609 eV), beryl (15.965 Å, 826–2271 eV),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)
E/ΔE = 1500 for beryl and InSb
Photoabsorption spectroscopy (total electron yield using EM and partial
fluorescence yield using SDD)

17
17

BL2B

Photoelectron spectroscopy of molecular solids
Ⅱ▼Description
This beamline previously dedicated for experiments in the field of gas phase photoionization and reaction
dynamics. Then, the beamline has been reconstructed for photoelectron spectroscopy of molecular solids with a
new end station, and experiments can be performed from May 2014. The monochromator is a spherical grating
Dragon type with 18-m focal length. High throughput (1  1010 photons s-1) and high resolution (E/E = 2000 8000) are achieved simultaneously under the condition of the ring current of 100 mA [1]. The optical system
consists of two pre-focusing mirrors, an entrance slit, three spherical gratings (G1 - G3), two folding mirrors, amovable 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 = 18m) at 40–100 eV; G3 (2400 lines mm-1, R = 9.25 m) at 23–50 eV. The percentage of the second-order light
contamination at h = 45.6 eV is 23% for G2 or 7% for G3.
A UHV chamber is placed downstream of the refocusing mirror chamber and equipped silicon photodiode,sapphire plate Au mesh and filters for absolute photon flux measurement, monitor the photon-beam position,
relative photon flux measurements and attenuate higher order light, respectively.
The new end station consists of a main chamber with a hemispherical analyzer (SCIENTA R3000) and aliquid-He-cooled cryostat (temperature range of 15-400 K) with 5-axis stage, a sample preparation chamber witha fast-entry load-lock chamber and a cleaning chamber with LEED, ion gun for sputtering and IR heating unit.
[1] M. Ono, H. Yoshida, H. Hattori and K. Mitsuke, Nucl. Instrum. Meth. Phys. Res. A 467-468 (2001) 577.
[2] H. Yoshida and K. Mitsuke, J. Synchrotron Radiation 5 (1998) 774.

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

Fig. 2. End station of BL2B for photoelectron
spectroscopy of molecular solids.

▼Technical Data
Monochromator

18 m spherical grating Dragon-type

Wavelength Range

23-205 eVResolution

2000–8000 depending on the gratings

Experiments

Angle-resolved ultraviolet photoelectron spectroscopy

18
18

BL3U

Varied-Line-Spacing Plane Grating Monochromatorfor Molecular Soft X-Ray Spectroscopy▼Description
The beamline BL3U is equipped with an in-vacuum 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. Three holographically ruled laminar
profile plane gratings are designed to cover the photon energy range from 40 to 800 eV. The beamline has liquidcells for soft X-ray absorption spectroscopy (XAS) in transmission mode as shown in Fig. 1. The liquid cell is in
the atmospheric helium condition, which is separated by a 100 nm thick Si3N4 membrane with the window sizeof 0.2 × 0.2 mm2 from the beamline in an ultrahigh vacuum condition. The thin liquid layer is assembled byusing two 100 nm thick Si3N4 membranes. The thickness of the liquid layer is controllable from 20 to 2000 nm
by adjusting the helium pressures around the liquid cell in order to transmit soft X-rays. Liquid samples areexchangeable in situ by using a tubing pump. The liquid cell has two types of windows: one is the liquid part toobtain the soft X-ray transmission of liquid (I), and the other is the blank part to obtain the transmission withoutliquid (I0). We can obtain the reliable XAS spectra based on the Lambert-Beer law ln(I0/I). Since the liquid cell isin the atmospheric condition, we can measure XAS of liquid samples in the real environment. Operando XAS
observation of several chemical reactions such as catalytic, electrochemical reactions are also possible by using
our liquid cells developed for these purposes.

Fig. 1. (a) Schematics of a liquid cell for XAS in transmission mode settled in BL3U. The blowup shows a thinliquid layer assembled by two Si3N4 membranes with the thickness of 100 nm. (b) Photograph of a XAS
measurement system for liquid samples at the end station of BL3U.

▼Technical Data
Monochromator
Energy Range
Resolution
Experiments

Varied-line-spacing plane grating monochromator
40-800 eV
E / ΔE > 10 000
Soft X-ray absorption spectroscopy of liquid in transmission mode

19
19

Ⅱ

BL3B (HOTRLU)Ⅱ

VIS-VUV Photoluminescence and Reflection/Absorption
Spectroscopy▼Description
BL3B has been constructed to study photoluminescence (PL) in the visible (VIS) to vacuum ultraviolet (VUV)
region. This beamline consists of a 2.5 m off-plane Eagle type normal-incidence monochromator, which covers
the VUV, UV, and VIS regions, i.e., the energy (wavelength) region of 1.7-31 eV (40-730 nm), with threespherical gratings having constant grooving densities of 1200, 600, and 300 l/mm optimized at the photon
energies of ~20, ~16, and ~6 eV, respectively. The schematic side view and top view layouts are shown in Figs.
1(a) and 1(b), respectively. The FWHM of the beam spot at the sample position is 0.25 mm (V) × 0.75 mm (H).
Low energy pass filters (LiF, quartz, WG32, OG53) can be inserted automatically to maintain the optical purity
in the G3 (300 l/mm) grating region (1.7~11.8 eV). Figure 2 shows the throughput spectra (photon numbers at abeam current of 300 mA) for each grating with entrance and exit slit openings of 0.1 mm (resolving power E /E of ~2000 (G3, ~6.8 eV)). Since both slits can be opened up to 0.5 mm, a monochromatized photon flux of1010 photons/s or higher is available for PL measurements in the whole energy region.
The end station is equipped with a liquid-helium-flow type cryostat for sample cooling and two detectors; oneof which is a photomultiplier with sodium salicylate and the other a Si photodiode for reflection/absorption
measurement. For the PL measurements in the wide energy region from VIS to VUV, two PL monochromators,
comprising not only a conventional VIS monochromator but also a VUV monochromator with a CCD detector,
are installed at the end station.

Fig. 1. Schematic layout of the BL3B (a) side view and (b)top view.

Fig. 2. Throughput spectra for eachgrating (G1:1200 l/mm, G2:600 l/mm andG3:300 l/mm) with S1 = S2 = 0.1 mm.

▼Technical Data
Monochromator-2.5 m normal-incidence monochromator

Energy range

1.7-31 eV (40~730 nm)

Resolution (h/ h) 12000 (at ~ 6.9 eV, 0.02 mm slits, G1 (1200 l/mm)

Experiments

Photoluminescence, reflection, and absorption spectroscopy, mainly for solids

20
20

BL4U

Scanning Transmission X-ray Microscopy in the Soft X-ray Region
Ⅱ▼Description
In the soft x-ray region, there are several absorption edges of light elements and transition metals. The nearedge X-ray absorption fine structure (NEXAFS) brings detailed information about the chemical state of target
elements. A scanning transmission X-ray microscope (STXM) in the soft X-ray region is a kind of extended
technique of the NEXAFS with high spatial resolution. The STXM has a capability of several additional options,for example, in-situ observations, 3-dimensional observation by computed tomography and ptychography, byutilizing the characteristics of the X-rays. The STXM can be applied to several sciences, such as polymer science,material science, cell biology, environmental science, and so on.
This beamline equips an in-vacuum undulator, a varied-line-spacing plane grating monochromator and a fixed exit
slit. The soft X-ray energy range from 50 to 770 eV with the resolving power (E/E) of 6,000 is available. The
aperture size of the fixed exit slit determines not only the resolving power but also the size of a microprobe. A Fresnel
zone plate is used as a focusing optical device through an order select aperture and its focal spot size of ~30 nm isavailable at minimum. An image is acquired by detecting intensities of the transmitted X-rays by a photomultipliertube with scintillator with scanning a sample 2-dimensionally. By changing the energy of the incident beam, each2-dimensional NEXAFS image is stacked. A main chamber of STXM is separated from the beamline optics by asilicon nitride membrane of 50-nm thickness; therefore, sample folders can be handled in vacuum or in helium.

PinholeSlit

M0 mirror

M1 mirror andGrating

M2 mirror

Fixed exit slit

STXM

Fig. 1. Schematic image of BL4U

Monochromatized X-rays

Fresnel zone plate
Order Sorting Aperture
SamplePhoto multiplier tube
with scintillator P-43

Central stopper
Fig. 2. Schematic image of STXM

▼Technical Data
Energy range (E)50 -770 eVResolving power (E/E)~6,000Focusing optical element

Fresnel zone plate

Spatial resolution~30 nmExperiments

2-dimensional absorption spectroscopy
standard sample folder in vacuum or in helium,
specially designed sample cell in ambient condition

Measurement environment

21
21

BL4B

▼Description
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 to 800 eV. The gratings with 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 thevacuum. Figure 1 shows the absolute photon flux for each grating measured using a Si photodiode (IRD Inc.),with the entrance- and exit-slit openings set at 50 and 50 μm, respectively. The maximum resolving power(E/ΔE) achieved for each grating exceeds 5000.
There is no fixed endstation on this beamline. A small vacuum chamber equipped with an electron multiplier(EM) detector is available. Soft X-ray absorption spectra of solid samples are usually measured by means of
the total electron yield method using EM, and the partial fluorescence yield method using a silicon drift detector(SDD).

1E12

G3
Intensity (photons/s)

Ⅱ

Varied-Line-Spacing Plane Grating Monochromatorfor Molecular Soft X-Ray Spectroscopy

1E11

Slit: 50m-50m

G2

1E10

G1
1E9

1E8
0

200

400

600

800

1000

1200

Photon Energy (eV)Fig. 1. Throughput from the VLS-PGM monochromatoron BL4B.

Fig. 2. Photo of BL4B.

▼Technical Data
Monochromator

Varied-line-spacing Plane Grating Monochromator

Energy range

25-1000 eVResolution

E / ΔE > 5000 (at maximum)

Experiments

Soft X-ray spectroscopy (mainly, photoabsorption spectroscopy for solid targets
by means of total electron yield method using EM and partial fluorescence yield
method using SDD)

22
22

BL5U

Photoemission Spectroscopy of Solids and Surfaces
Ⅱ▼Description
Since the monochromator of BL5U was an old-style spherical grating type SGMTRAIN constructed in 1990s
and the throughput intensity and energy resolution were poor, the whole beamline has been replaced tostate-of-the-art monochromator and end station. The new beamline has been opened to users from FY2016 as
high-energy resolution ARPES beamline. Samples can be cooled down to 3.8 K with newly developed 5-axis
manipulator to perform high energy resolution measurements. Users can also obtain spatial-dependence of theelectronic structure of solids using micro-focused beam (~ 50 μm). The new electron lens system makes it
possible to obtain ARPES spectra without moving samples. This beamline will also have new capability toperform high-efficient spin-resolved ARPES in the future.

Fig. 1. Pictures of BL5U.

▼Technical Data (Expected Performance)
Light source

APPLE-II type undulator (λu = 60 mm, N = 38)
vertical/horizontal, right/left circular (depending on hv)

Monochromator

Monk-Gillieson VLS-PGM

Energy Range

20-200 eVResolution

hv/ ΔE > 10,000 for < 10 μm slits

Experiment

ARPES, Space-resolved ARPES, Spin-resolved ARPES

Flux<1012 photons/s for <10 μm slits (at the sample position)

Beam spot size

23 (H) x 40 (V) µm

Main Instruments

Hemispherical photoelectron analyzer with deflector scan (MBS A-1 Lens#4),
Liq-He flow cryostat with 5-axis manipulator (3.8 K-350 K)

23
23

BL5B

Calibration Apparatus for Optical Elements and Detectors
Ⅱ▼Description
BL5B has been constructed to perform calibration measurements for optical elements and detectors. This
beamline is composed of a plane grating monochromator (PGM) and three endstations in tandem. The most
upstream station is used for the calibration measurements of optical elements, the middle one for opticalmeasurements for solids, and the last for photo-stimulated desorption experiments. The experimental chamber at
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 optical elements,
which has six degrees of freedom, X-Y translation of a sample, and interchanging of samples and filters. These
are driven by pulse motors in vacuum. Because the polarization of synchrotron radiation is essential for suchmeasurements, the rotation axis can be made in either the horizontal or vertical direction (s- or p-polarization).

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

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

▼Technical Data
Monochromator

Plane Grating Monochromator

Energy range

6-600 eV (2-200 nm)

Resolution

E / ΔE ~500

Experiments

Calibration of optical elements, reflection and absorption spectroscopy mainly
for solids

24
24

BL6U

Variable-Included-Angle / Variable-Line-Spacing Plane Grating
Monochromator for Soft X-Ray photoelectron Spectroscopy▼Description
The beamline BL6U equipped with a variable-included-angle Monk-Gillieson mounting monochromator witha varied-line-spacing plane grating was constructed for various spectroscopic investigations requiringhigh-brilliance soft X-rays on solid surfaces. Through a combination of undulator radiation and sophisticatedmonochromator design (entrance slit-less configuration and variable-included-angle mechanism), using asingle grating, the monochromator can cover the photon energy ranging from 40 to 500 eV, with resolving powerof greater than 10000 and photon flux of more than 1010 photons/s. Figure 1 shows an example of themonochromator throughput spectra measured using a Si photodiode, with the exit-slit opening set at 30 μm,
which corresponds to the theoretical resolving power of 10000 at 80 eV.
The end station is equipped with an electron energy analyzer for angle-resolved photoelectron spectroscopy(MB Scientific AB, A-1 analyzer Lens#5). This spectrometer consists of a hemispherical electron analyzer
with a mechanical deflector and a mesh electrostatic lens near the sample to make the acceptance cone tunable. A
constant energy angular distribution of the valence band dispersion cross section in the large k range can be
efficiently obtained by applying a negative bias voltage to the sample and using the mechanical deflector.

Throughput spectra of the BL6U (Gap=13 mm, Slit=30m)

Flux(Photons/s/100mA:PD-AXUV100G)

1E13

3rd

1E12

5th

1st

1E11

168170
172174

1E10
1E9
1E8
1E7

30

100

Photon energy(eV)Fig. 1. Throughput spectra of the BL6U monochromator atvarious included angles.

Fig. 2. Photograph of BL6U end station.

▼Technical Data
Monochromator

Variable-included-angle Varied-line-spacing Plane Grating Monochromator

Energy range

45-600 eV(practical)

Resolution

E / ΔE > 10000 (at maximum)

Experiments

High-resolution soft X-ray spectroscopy (photoelectron spectroscopy for solid surfaces)

25
25

Ⅱ

BL6B

Infrared and Terahertz Spectroscopy of Solids
Ⅱ▼Description
Synchrotron radiation (SR) has good performance (high brilliance and high flux) not only in the VUV and soft
X-ray (SX) regions but also in the infrared (IR) and THz regions. BL6B covers the IR and THz regions. The
previous beamline, BL6A1, which was constructed in 1985, was the pioneer in IRSR research. The beamline
was deactivated at the end of FY2003 and a new IR/THz beamline, BL6B (IR), was constructed in FY2004. The
front-end part including bending duct #6 was replaced with a new part having a higher acceptance angle (215
(H)  80 (V) mrad2) using a magic mirror, as shown in Fig. 1.
There are two Michelson type interferometers in this endstation; with first one (Bruker Vertex70v), which
covers a wide spectral region from 30 to 20,000 cm-1 (h = 4 meV-2.5 eV), reflection/absorption spectroscopy
measurements of large samples (up to several mm) and IR/THz microscopy measurements of tiny samples (up to
several tens of m) can be performed. For reflection/absorption spectroscopy measurements, a liquid-heliumflow type cryostat with a minimum temperature of 4 K is installed. The other interferometer (Jasco FT/IR-6100),
which covers 350 to 15,000 cm-1 (h = 45 meV-1.8 eV), has been available for IR microscopy imaging
measurements from FY2014. One can also perform ATR measurements using diamond ATR prism.

Reflection/absorption
end station

Michelson FT-IR(Jasco FT/IR-6100)

IR microscopy imaging(Jasco IRT-7100)

Fig. 1. Design of the optics and front end of BL6B.

Michelson FT-IR(Jasco FT/IR-6100)

Fig. 2. Schematic top view of BL6B.

▼Technical Data
Interferometer

Michelson (Bruker Vertex70v)

Michelson (Jasco FT/IR-6100)

Wavenumber Range(Energy range)

30-20,000 cm-1
(4 meV-2.5 eV)

350-15,000 cm-1
(45 meV-1.8 eV)Resolution in cm-1

0.1 cm-1

0.5 cm-1

Experiments

Reflectivity and transmission
spectroscopy
THz Microspectroscopy

IR microscopy imaging (JASCO IRT-7000)
ATR spectroscopy

26
26

BL7U (SAMRAI)

Angle-Resolved Photoemission of Solids in the VUV Region
Ⅱ▼Description
Beamline 7U, named the Symmetry- And Momentum-Resolved electronic structure Analysis Instrument(SAMRAI) for functional materials, was constructed to provide a photon flux with high energy resolution andhigh flux mainly for high-resolution angle-resolved photoemission spectroscopy, so-called “ARPES”, of solids[1]. An APPLE-II-type variable-polarization undulator is installed as the light source. The undulator can produce
intense VUV light with horizontal/vertical linear and right/left circular polarization. The undulator light ismonochromatized by a modified Wadsworth type monochromator with three gratings (10 m radius; 1200, 2400,
and 3600 lines/mm optimized at hv = 10, 20, and 33 eV). The energy resolution of the light (hv/Δhv) is more than
104 with a photon flux of 1011-1012 ph/s or higher on samples in the entire energy region. The beamline has aphotoemission end-station equipped with a 200 mm-radius hemispherical photoelectron analyzer (MB Scientific
AB, A-l analyzer) with a wide-angle electron lens and a liquid-helium-cooled cryostat with 6-axis pulse motor
control. The main function of the beamline is to determine the electronic structure of solids and its temperaturedependence in order to reveal the origin of their physical properties.
[1] S. Kimura, T. Ito, M. Sakai, E. Nakamura, N. Kondo, K. Hayashi, T. Horigome, M. Hosaka, M. Katoh, T. Goto,
T. Ejima and K. Soda, Rev. Sci. Instrum. 81 (2010) 053104.

Fig. 1. SAMRAI beamline [(a), (b)]consisting of an APPLE-II typeundulator (U7), a modified Wadsworth
type monochromator (M0-S), and ahigh-resolution photoemission analyzer
at the focal point. The monochromator
has five major optical components: twoplane mirrors (M0 and M1) with watercooling, one set of three sphericalgratings (G), an exit slit (S), and one
toroidal refocusing mirror (M3). (c)Example of flux intensity versus photon
energy [1]▼Technical Data
Light source

APPLE-II type undulator (λu = 76 mm, N = 36)vertical/horizontal, right/left circular (depending on hv)

Monochromator

10 m normal-incidence monochromator (modified Wadsworth type)

Photon energy range

6 – 40 eV (λ = 30 – 200 nm)

Resolution (hv/Δhv)

E / ΔE > 10000-50000

Photon flux on sample

 1011-1012 ph/s (depending on hv)

Beam size on sample

200 (H) × 50 (V) μm2

Experiments

Angle-resolved photoemission of solids(MV Scientific A-1 analyzer, acceptance angle: ± 18 deg)

27
27

BL7B

3 m Normal-Incidence Monochromator for Solid-State Spectroscopy
Ⅱ▼Description
BL7B has been constructed to provide sufficiently high resolution for conventional solid-state spectroscopy,
sufficient intensity for luminescence measurements, wide wavelength coverage for Kramers–Kronig analyses,
and minimum deformation to the polarization characteristic of incident synchrotron radiation. This beamline
consists of a 3-m normal incidence monochromator, which covers the vacuum ultraviolet, ultraviolet, visible,
and infrared, i.e., the wavelength region of 50–1000 nm, with three gratings (1200, 600, and 300 l/mm). Twointerchangeable refocusing mirrors provide two different focusing positions. For the mirror with the longer focal
length, an LiF or a MgF2 window valve can be installed between the end valve of the beamline and the focusing
position. Figure 1 shows the 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 to measure the photon intensity and theabsolute photon flux was estimated, taking the quantum efficiency of the photodiode into account.

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

Fig. 2. Photo of BL7B.

▼Technical Data
Monochromator

3 m Normal-Incidence Monochromator

Wavelength Range

50-1000 nm (1.2-25 eV)Resolution

E / E = 4000-8000 for 0.01 mm slits

Experiments

Absorption, reflection, and fluorescence spectroscopy, mainly for solids

2828