Ⅱ

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

Light Source in 2016
1. Status of UVSOR Accelerators

suspected that a leakage took place around the frontend
of a beam-line, BL3U. This was confirmed by opening
the vacuum system on 25th Nov. We found that thecooling water of a mask in the frontend of the beamline was leaking out to the ultrahigh vacuum. We
separated the beam-line from the storage ring by a gate
valve and started the recovery work, which involved
the baking of the entire ring. After the preparation
works, we started the baking of a half of the ring on 5th
Dec. and another half on 12th Dec., both of which we
continued for one week. We started the machine
operation for the vacuum conditioning by synchrotron
radiation on 19th Dec. We restarted the user operation
on 17th Jan. The beam lifetime recovery during thevacuum conditioning run is shown in Fig. 2.

In the fiscal year 2016, we had scheduled to operate
UVSOR-III from May to March, for 38 weeks forusers as usual. However, due to a vacuum leakage
trouble at the frontend of a beamline and the following
recovery works, we canceled the user runs for fourweeks and a half in November and December. We had
a scheduled shutdown period in April and May forabout 6 weeks. This was for the scheduled maintenanceworks and for replacing the RF power amplifier of thestorage ring and the power supply for the injection
septum of the booster-synchrotron.
We operated the machine for 31 weeks and a halfin the multi-bunch top-up mode, in which the beam
current was kept at 300 mA, and 1 week in the singlebunch mode, in which the machine was operated insingle-bunch top-up mode with the beam current ofapproximately 40 mA. The monthly statistics of theoperation time and the integrated beam current are
shown in Fig. 1. The deep dip around December was
due to the vacuum trouble and the recovery work.

Fig. 2. The lifetime recovery during the vacuum
conditioning runs in Dec. 2016 and Jan. 2017. The
horizontal axis is the integrated beam current and thevertical axis is the life time multiplied by the beam
current ( Iτ ). The lifetime just before the vacuum
accident is shown by a blue dotted line.

Fig. 1. Monthly statistics in FY2016.
The weekly operation schedule is as follows. On
Monday, from 9 am to 9 pm, the machine is operated
for machine studies. On Tuesday and Wednesday, from
9 am to 9 pm, the machine is operated for users. From
Thursday 9 am to Friday 9 pm, the machine is operated
for 36 hours continuously for users. Therefore, thebeam time for users in a week is 60 hours. We had 3
weeks dedicated for machine studies, in November,just after the New Year vacation and the last week inMarch. The machine study week in November ismainly dedicated for the accelerator conditioning after
the annual planned power outage.
As described above, the most serious trouble in thisyear was the vacuum leakage that happened on 23th
Nov. Just after the scheduled beam dump at 9 pm, thevacuum of the storage ring steeply rose. From therecord of the vacuum pressure around the ring, it was

In this year, other than the vacuum trouble describedabove, we had a few minor troubles on the power
supplies of the injection/extraction magnets. However,
fortunately, in all cases the beam time for users was not
lost. The water leakages from a quadrupole magnet in
the booster synchrotron happened but it was recoveredby replacing the water cooling pipe during the shutdown period.
2. Improvements and Developments
The solid state 90 MHz RF power amplifiers of thebooster synchrotron and of the storage ring had beenused for about 20 years. They had been working wellwithout any serious problem. However it became
difficult to maintain them because of the outage of

9

9

Ⅱ

Ⅱ . Current Status of Light Sources and Beamlines

Ⅱelectronic parts. We decided to replace the amplifierswith new ones which have basically same
performances but much smaller sizes and are watercooled. We expect that the water cooling would be
beneficial to stabilize the accelerator room temperature
and also to reduce the sound noise in the experimental
hall. In the spring shut down 2015, we replaced theamplifier for the booster synchrotron. It had beenworking well without any serious problem for one year.
Then, in this year, we have replaced that of the storage
ring. The new RF amplifier had an electric noiseproblem, however, it was soon improved by adding
some filters.

UV range, we could precisely investigate the opticalproperties of the vortex beams from undulators in thiswavelength range using conventional opticalcomponents such as a UV-CCD camera, bandpass
filters and so on. In the spring shut down 2016, we
collaborated with the beamline staffs, and installed amirror and a monochromator at BL1U, which would be
used for exploring the applications of novel lightsources. By using this beam-line, we continued theexperimental study on the interaction between opticalvortex VUV light and atoms in collaboration with Saga
LS and Niigata U. [1]. As a theoretical work, we havesuccessfully shown that the origin of the vortex natureof the undulator radiation was in the radiation from anelectron in circular motion [2].
We are continuing the effort to reconstruct the
optical cavity for the resonator free electron laser at
BL1U, which has been investigated for many years at
UVSOR. This time, the main objective is the high flux
intra-cavity gamma-ray production for the nuclear
resonance fluorescence imaging in cooperation with
Kyoto University. Currently gamma-rays are produced
by using conventional fiber laser for the proof-ofprinciple study [3]. The gamma-rays are also used forinvestigating the origin of the homo-chirality of
biomolecules in nature in collaboration with HiroshimaU., Yokohama N. U. and others.
Irradiation experiments using polarized ultraviolet
light are being carried out in corporation with Tokyo U.
Sci. and with Yokohama N. U and Hiroshima U. In thelatter case, the circularly polarized UV-VUV light wasused for the study on the origin of homo-chirality [4]A spin polarized electron gun is being developed incollaboration with Nagoya U. and KEK. This year,
the temporal response of the photocathode wasinvestigated by using femto-second laser system at
BL1U [5].
We continued designing a new harmonic cavity incollaboration with Nagoya U., to replace the present
cavity which has a vacuum trouble. For this design
study, we have started investigating present beam
instabilities at UVSOR-III [6].

Fig. 3. An open space appeared in the storage ringafter removing the old RF power amplifier.

Light Source Developments and Beam Physics
Studies
We continue the efforts to develop light sources
technologies and their applications such as free electron
lasers, coherent harmonic generation, coherent
synchrotron radiation, laser Compton scattering gammarays, intense polarized and vortex UV radiation at the
new source development station BL1U, which wasconstructed under the support of Quantum BeamTechnology Program by MEXT/JST. This beam-line isdedicated to develop light source technologies and to
explore their applications.
This year, we continued studying the optical vortex
beam from a helical undulator in collaboration with
Hiroshima U., Nagoya U. and other institutes. Since
the UVSOR electron beam is diffraction-limited in the[1] T. Kaneyasu et al., in these reports[2] M. Katoh et al., in these reports[3] H. Zen et al., in these reports[4] K. Matsuo et al., in these reports[5] N. Yamamoto et al., in these reports[6] A. Mochihashi et al., in these reports
Masahiro KATOH (UVSOR Facility)

1010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

Ⅱ

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

Position [m]Horizontal/verticalelectron beam sizeand beam divergences

σx,y [mm]σ'x,y [mrad]ηx√βx,y [√m]

Horizontal/verticalbetatron functions
and dispersion function

11

11

Position [m]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
15-40 mm2.0-0.24

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

12

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

Beamlines in 2016
Kiyohisa TANAKAUVSOR 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 the extremeultraviolet 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 five insertion devices areavailable as synchrotron light sources at UVSOR. As
of 2015 there are a total of fourteen operational
beamlines, which are classified into two categories.
Eleven of them are the so-called “Open beamlines”,
which are open to scientists from universities andresearch institutes belonging to the government, publicorganizations, private enterprises and also those fromforeign countries. The remaining three beamlines are
the “In-house beamlines”, and are dedicated to the useof 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) stations with normal incidence monochromators,
two infrared (IR) stations equipped with FourierTransform interferometers, and one free electron laser
beamline with no monochromator, as shown in the
appended table (next page) for all available beamlines at
UVSOR in 2016.
In November 2016, there was a serious vacuum
leakage accident from water cooling line at a fourquadrant copper mask located at upstream of BL3U. It
was installed 10 years ago, and cooling water made ahole through 1 mm thick copper pipe. Since theaccident occurred just after user operation, all upper
most valves of beamlines were closed and the effectwas limited to the storage ring. The whole storage ringhas been baked after the four-quadrant copper mask
was removed. User operation was restarted from 17th
January, which means users lost beamtime for five
weeks. The pipe which made leakage will be modified
to 3 mm thickness one and will be installed during the
shutdown of 2017. There are three more similar type ofmasks installed in the storage ring, and they will bealso replaced during the shutdown. Users who lost
beamtime were reassigned to the open beamtime

according to their request. If there was no beamtime
left, users lost beamtime. The loss of beamtime will beconsidered during the peer review process of the next
beamtime request in FY 2017. In BL4U, where there
are many users from companies and minimum
beamtime is one day, the rest of the whole beamtime
was rescheduled.
BL2A equipped with a double-crystal monochromator,
where users can use the highest energy photons in
UVSOR (~4 keV), has been used mainly forphotoabsorption spectroscopy. Since there are users
who want to evaluate the sample surface, a newchamber for X-ray photoemission spectroscopy (XPS)
has been prepared offline. This system will be attached
to BL2A during the shutdown of 2017.
In BL3B, to achieve high efficiency VUV emission
spectroscopy, a new endstation chamber has been
designed and manufactured in 2016. It will be available
from FY 2017.
BL6B is an Infrared-THz beamline which has
confocal type micro-spectroscope station, reflection/transmission station, and IR microscope imaging
station. To solve serious long term drift of beam pathcaused by M0 magic mirror thermal load, the feedback
control system of M0 mirror angle by monitoring thereflection of visible laser from M0 mirror has beendeveloped. This feedback control system has beenroutinely operated and successfully provide stablebeam for users from this year.
BL5U has been officially opened for users from 2016as high energy resolution angle-resolved photoemission
spectroscopy (ARPES) beamline. It became one of themost popular beamline in UVSOR, whose beamtime
requests are about three times more than the beamtime.
Space-resolved and spin-resolved function will be
developed and installed in one year.
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 2010), on the occasion of conducting theactual experimental procedures. Those wishing to use
the open and in-house beamlines are recommended tocontact the appropriate beamline master (see nextpage). For updated information on UVSOR, pleasesee http://www.uvsor.ims.ac.jp.

1313

Ⅱ . Current Status of Light Sources and Beamlines

Beamlines at UVSOR
Beamline

Ⅱ

Monochromator /Spectrometer

BL1U

Free electron laser

BL1B

Martin-Puplett FT-FIR

BL2A

BL3U*

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

BL3B

2.5-m off-plane Eagle

BL4B
BL5U
BL5B

0.5 - 30 meV
585 eV - 4 keV

18-m spherical grating(Dragon)Varied-line-spacing
plane grating(Monk-Gillieson)
Varied-line-spacing
plane grating(Monk-Gillieson)
Varied-line-spacing
plane grating(Monk-Gillieson)
Plane grating

23 - 205 eV
60 - 800 eV

1.7 - 31 eV

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

BL6B

Michelson FT-IR

BL7U

10-m normal incidence(modified Wadsworth)BL7B

3-m normal incidence

Techniques

Contact
M. Katohmkatoh@ims.ac.jp

Solid

Reflection
Absorption

F. Teshima

Solid

Reflection
Absorption

N. Kondo

Solid

Photoemission

S. KeraGas
LiquidSolid

Absorption
Photoemission
Photon-emission
Reflection
Absorption
Photon-emission

Solidtetsu@ims.ac.jp

nkondo@ims.ac.jp

kera@ims.ac.jp

N. Kosugi

kosugi@ims.ac.jp

M. Hasumoto

hasumoto@ims.ac.jp

130 - 700 eV

Gas
LiquidSolid

Absorption(Microscopy)

T. Ohigashi

25 eV - 1 keV

Gas
Solid

Photoionization
Photodissociation
Photoemission

E. Shigemasa

Solid

Photoemission

M. SakaiSolidCalibration
Absorption

M. Hasumoto

20 - 200 eV

6 - 600 eV

BL6U*

Targets

1.6 - 13.9 eV

Double crystal

BL2B

BL4U

Energy Range

40 - 800 eV
4 meV - 2.5 eV
6 - 40 eV
1.2 - 25 eV

Yellow columns represent undulator beamlines.
*
In-house beamline.

14
14

Gas
Solid
Solid

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

sigemasa@ims.ac.jp

sakai@ims.ac.jp

hasumoto@ims.ac.jp

E. Shigemasa

sigemasa@ims.ac.jp

F. Teshimatetsu@ims.ac.jp

Solid

Photoemission

S. Ideta

Solid

Reflection
Absorption
Photon-emission

M. Hasumoto

idetas@ims.ac.jp

hasumoto@ims.ac.jp

BL1U

Light Source Development Station
Ⅱ▼Description
BL1U has being constructed for developments and applications of various photon sources including freeelectron 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 opticalvortices.
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
Wavenumber range

Martin-Puplett (JASCO FARIS-1)
4-240 cm-1

(Energy range)(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-A l2O3, 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 th e
monochromator 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.

Photon Flux(photons/sec./100mA)[1] Hiraya et 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
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.

▼Technical Data
Monochromator
Wavelength Range
Resolution
Experiments

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

18 m spherical grating Dragon-type
23-205 eV
2000-8000 depending on the gratings
Angle-resolved ultraviolet photoemission 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 including soft X-ray emission studies.
Three holographically ruled laminar profile plane gratings are designed to cover the photon energy range from60 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 by aplane-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. XAS of liquid samples and the application of in
operando observations are performed at the experimental stage of the multi-purpose setup.

S0

Top View
in-vacuum
plane undulator

M0: Cylindrical
R=47.253 m

XES Setup
M1: Spherical G: VLSP
R=88.826 m

S1X
sample176°

M2X: Plane-Elliptical
r1=11.7 m
r2=0.5 m

M2: Toroidal
R= 81.65 m
 = 37.23 mm

Multi-purpose setup S1

sample

176°
700
0

5300

3100
6000

400
9100

2203
9500

G

Side View
177°

S0

176°

500
11703

800
12203

1600
13003

14603

S1X

M2X

sample

173°

M1

S1

M0

M2

sampleFig. 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 millimeters. S1X and M2X can be replaced with the otherexit slit S1 so that experiments can be carried out at either the XES or the multipurpose endstation. In the XES
setup, the sample is placed 5–10 mm downstream of S1X.

▼Technical Data
Monochromator
Energy Range
Resolution
Experiments
Beam Size(XES Endstation)

Varied-line-spacing plane grating monochromator
60-800 eV
E / ΔE > 10 000
Soft X-ray spectroscopy (XPS, XES, XAS)
Gaussian shape
Vertical 5-20 μm; Horizontal 41 μm (FWHM)

19
19

Ⅱ

BL3B (HOTRLU)▼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.

9

Photon Number (x10 /s/300mA)

Ⅱ

VIS-VUV Photoluminescence and Reflection/Absorption
Spectroscopy

(b)

(a)

3.0
2.5

G3
G2
G1

2.0
1.5
1.0
0.5
0.0

0

10

20

30

40

Photon Energy (eV)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 100 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 100-nm thickness; therefore, sample folders can be handled in vacuum or in helium.

Slit

PinholeM0 mirror

M1 mirror andGrating

M2 mirror

Fixed exit slit

Fig. 1. Schematic image of BL4U
Fresnel zone plate

Order sorting aperture
Photo multiplier tube
with scintillator

Monochromatized X-ray
SampleFig. 2. Schematic image of the STXM

▼Technical Data
Energy range (E)100-770 eVResolving power (E/E)~6,000Focusing optical element

Fresnel zone plate

Spatial resolution~30 nmExperiments

2-dimensinal absorption spectroscopy

Measurement environment

standard sample folder in vacuum or in helium,
specially designed sample cell in ambient condition

21

21

STXM

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. Fig. 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/E) 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 / E > 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
This beamline was originally used for angle-resolved photoemission spectroscopy (ARPES) study of solids
and surfaces. After Jan 2014, the beamline had been shutdown for upgrade. The whole beamline, including theundulator and the endstation, is renewed to perform higher energy resolution ARPES experiments. This beamline
will also have new capability to obtain spin- and spatial-dependence of the electronic structure of solids using
new spin detector and micro-focused beam. This beamline is opened for users from 2016.

Fig. 1. Pictures of BL5U on May 2014.

▼Technical Data (Expected Performance)
Monochromator
Energy Range
Resolution
Experiment
Flux

Monk-Gillieson VLS-PGM
20-200 eVh / E > 10,000 for < 10 µm slits
ARPES, Spin-resolved ARPES, Space-resolved ARPES<1012 photons/s for <10 µm slits (at the sample position)

Beam spot size
Main Instruments

400 (H) x 5-20 (V) µm, 10 (H) x 4-6 (V) µm (microscope)
Hemispherical photoelectron analyzer (MBS A-1), Liq-He flow cryostat with
5-axis manipulator (5-400 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 / E500

Experiments

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

24
24

BL6U

Variable-Included-Angle VLS-PGM for Molecular Soft X-Ray
Spectroscopy▼Description
The beamline BL6U equipped with a variable-included-angle Monk-Gillieson mounting monochromator with avaried-line-spacing plane grating was constructed for various spectroscopic investigations requiring high-brilliancesoft X-rays in a gas phase and/or on solids. Through a combination of undulator radiation and sophisticatedmonochromator design (entrance slit-less configuration and variable-included-angle mechanism), using a single
grating, the monochromator can cover the photon energy ranging from 30 to 500 eV, with resolving power ofgreater 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, whichcorresponds to the theoretical resolving power of 10000 at 80 eV.
There is no fixed endstation on this beamline.

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
at various included angles.

Fig. 2. Photo of BL6U

▼Technical Data
Monochromator

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

Energy range

40-500 eVResolution

E / E > 10000 (at maximum)

Experiments

High-resolution soft X-ray spectroscopy (mainly photoelectron
spectroscopy for gaseous and solid targets)

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 awide spectral region from 30 to 20,000 cm-1 (h = 4 meV-2.5 eV), reflection/absorption spectroscopy measurements oflarge 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-helium-flow type cryostat with aminimum 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 canalso perform ATR measurements using diamond ATR prism.

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

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(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

-1

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 hν = 10, 2 0, and 33 eV). The energy resolution of the light (hν/Δhν 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 (AVC Co., Ltd., i-GONIO). The main function of the beamline is to determine the electronic structure ofsolids and its temperature dependence 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 hν)Monochromator
Photon energy range
Resolution (hν/Δhν)

10 m normal-incidence monochromator (modified Wadsworth type)6-40 eV (λ = 30-200 nm)
E / ΔE > 10000-50000

Photon flux on sample
Beam size on sample
Experiments

 1012-1011 ph/s (depending on hν)
200 (H) × 50 (V) µm2
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, andinfrared, 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 a silicon
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 / ΔE = 4000-8000 for 0.01 mm slits

Experiments

Absorption, reflection, and fluorescence spectroscopy, mainly for solids

28
28

UVSOR User 1

UVSOR User 2