Ⅲ-1

Accelerators andInstruments

BL3UⅢ -1. Accelerators and Instruments

BL3U

Development of Resonant Soft X-ray Scattering for Soft Materials at
UVSOR BL3U
2

H. Iwayama 1,2 and T. Horigome1

UVSOR Synchrotron Facility, Institute for Molecular Science, Okazaki 444-8585, Japan
School of Physical Sciences, The Graduate University for Advanced Studies, SOKENDAI, Okazaki 444-8585, Japan1

The liquid crystal is one of the most importantmaterials for display devices. Their molecules havecharacteristic shapes such as rod and disc. This enables
them to have both liquidity and symmetry of molecularalignments, which expresses interesting physicalproperty such as a birefringence. In particular, chiralliquid crystal materials can have various kinds of phase,
which are shown in Fig. 1. Depending on the phase, thesample is ferroelectric or anti-ferroelectric. In addition,
they have intermediate phases between ferroelectric andanti-ferroelectric. To understand these physical properties,
we need to know a periodic length of molecular layers,
d. A typical value of d is from several nm to 100 nm.
Since liquid crystal molecules mainly consist of lightelements such as carbon, nitrogen and oxygen, resonant
soft x-ray scattering is powerful tool.
We developed the equipment for resonant soft x-ray
scattering (RSoXS) measurements. Figure 2 shows aschematic draw of an experimental setup. Our sample is
S-MHPOBC and sandwiched between two 100 nmSi3N4 membranes to avoid evaporations in a vacuum
chamber. Sample can be heated up to 120 °C to observevarious kinds of chiral smetic phases. Experiments were
performed at UVSOR BL3U. Sample is irradiated with
soft x-rays and scattering x-rays are detected by x-ray
camera (Andor BN940P). We can measure scattering
angles from 15° to 45°.
Figure 3 shows diffraction images at resonance andnon-resonance photon energies and corresponding
scattering angles. Here resonance is C 1sπ* core
excitation, whose photon energy is hv = 285 eV (λ = 4.3
nm). For the resonance scattering, we found three ring
structures at y = -10, -4 and 8 mm. At the resonancephoton energy, intensities of ring structures at 8 mm
strongly increase. By using Bragg’s law, d =λ/2sinθ, we
obtained d spectra for resonance and non-resonance.
Here d is a periodic length, λ is a wavelength of photons,
and 2θ is a scattering angle. We find peaks at 6.4, 9.7
and 13.0 nm. Considering single molecular length of 3
nm, these peaks correspond to 2, 3 and 4 molecular layer.
Resonant enhancement of peak intensity for d = 6.4 nm
suggests that the phase of the sample is anti-ferroelectric.
Now we analyze the data in detail and investigate
intermediate phases between ferroelectric and antiferroelectric one.
The RSoXS technique enables us to probe meso-scale(nm - µm) structures with both elemental and chemical
environment sensitivity and is ideal tool to study mesoscale materials such as polymer, block copolymer,
composite morphology, particle assembly, organic

photovoltaic morphology, organic LEDs, membranes,
porous materials, batteries and fuel cells, biomaterials,
and so on [1].

Fig. 1. Schematic view of molecular alignments forvarious kinds of chiral smetic phases.

Fig. 2. Schematic draw of an new experimental setup
for resonant soft x-ray scattering.

Fig. 3. Diffraction images for resonance and offresonance and scattering angle map.
[1] F. Liu, M.A. Brady and C. Wang, Eur. Polym. J. 81(2016) 555.

33

Ⅲ -1

Others
Ⅲ -1. Accelerators
and Instruments

OthersDevelopment of Nuclear Emulsion with Different Silver Halide Crystal
Sizes for Cosmic-ray Imaging
A. Nishio, K. Morishima, K. Kuwabara, T. Yoshida and M. Nakamura
F-lab., Department of Physics, Nagoya University, Nagoya 464-8602, Japan

Ⅲ -1

Cosmic ray imaging is the a new non-destructive
inspection technique of large-scale constructions withcosmic ray muon. Cosmic ray muon has highpenetrating power and it always comes from the wholesky. In the same way of taking a X-ray photograph, we
can obtain integrated density of constructions which
thickness are several tens cm to several km. We had
ever applied this technique to the pyramid of khufu at
Egypt, and discovered a large void [1].
In cosmic-ray imaging observations, we usednuclear emulsion as a detector. Nuclear emulsion is akind of photographic film and has sensitivity forionizing radiation. The film records tracks of charged
particle with angular accuracy under several mrad. In
Nagoya University, started a emulsion gel production
machine in 2010. It was enabled us to develop new-type
emulsion gel by ourselves.
We have succeeded to develop the Large crystal
Nuclear Emulsion and the relationship between thesize of silver halide crystals in nuclear emulsion andtheir sensitivity to the minimum ionized particles wasinvestigated.
Gold-sulfur-sensitized silver iodobromide crystals
with a diameter of approximately 180 - 540 nm wereprepared (Fig.1), and their photo sensitivity andminimum ionized particle sensitivity were investigated.
First, we confirmed that the photo sensitivity was
proportional to the crystal volume and that the quantum
sensitivity to light was sufficiently high (Fig. 2).
After that, minimum ionized particle sensitivity wasinvestigated (Fig. 3). The grain density was found tobe 1.3 to 1.4 times higher with the same volume
occupancy of crystals by increasing the crystal size to
400 nm in diameter than the conventional size of 220
nm. It was also found that the grain density could not
be significantly increased due to the decrease in thenumber of crystals, even if the crystal size was larger
than 400 nm.

Fig. 1. EM images of silver halide crystals ofdifferent sizes.

Fig. 2. Relationship between photo sensitivity S(relative value) and crystal volume.

Fig. 3. Crystal size dependence of sensitivity to theminimum ionized particles; Grain density, Fog density,and detection efficiency per crystal.
[1] K. Morishima et al., Nature 552 (2017) 386.

34
Ⅲ01- 2 -Accelerators

Ⅲ -1. Accelerators and Instruments

Accelerators

Survey of Low Emittance Optics for UVSOR-III
2

E. Salehi1 and M. Katoh1,2

UVSOR Synchrotron Facility, Institute for Molecular Science, Okazaki 444-8585, Japan
Hiroshima Synchrotron Radiation Center, Hiroshima University, Higashi-Hiroshima 739-0046, Japan
1

This is a study on a future plan of UVSOR
synchrotron to provide diffraction-limited light in thevacuum ultraviolet range. For this purpose, the small
emittance less than at 1 nm is required. UVSOR is alow energy synchrotron light source. After some major
upgrades [1-4], it is now called UVSOR-III, which has
a moderately small emittance of about 17 nm andprovide vacuum ultraviolet light of high brightness.
As the first step of the study, we have analyzed thepresent magnetic lattice of UVSOR III to seek apossible low emittance without major changes of thelattice. We draw a “tie diagram” of UVSOR III as
shown in Fig.1, which indicates the quadrupole
parameter region where a periodic solution exists, aswell as the emittance of each parameter set is shownby the color. In reality, UVSOR-III has four
quadrupole families. However, to draw the tie diagram,they are grouped into two families (QF and QD)
located symmetrically around the bending magnets.
The code, Elegant [5], was used and the twoquadrupole strengths are surveyed. Figure 1 shows that
there are a few areas which has significantly smaller
emittance around 10 nm than the present value, 17 nm.
However, there seems no solution which gives theemittance much smaller than 10 nm. The hardware
limitations of the quadrupole field strengths areindicated in the figure. For the operation energy, 750
MeV, a part of the low emittance region is out of thelimitation. However, if the machine is operated at 600
MeV, most of the low emittance area is within thelimitation. It should be noted that the emittance is
proportional to the square of the electron energy, thelow energy operation would give even smaller
emittance.
On the tie diagram, we can find some solutions
which give a smaller emittance than the present value.
Making these parameters as the initial values for four
quadrupole families, we designed some optics which
may be worth to investigate further. The optic presented
in Fig. 2 has an emittance smaller than 10 nm at theelectron energy, 750 MeV. In this optics, the verticalbetatron function at the straight sections are not as
small as the present optics. Therefore, this optics may
not be compatible with the operation of the narrow gap
undulators. In some special studies which requires asmall emittance as possible, this optics may be useful.
Another interesting optic is shown in Fig. 3, which
gives a small emittance, 13 nm, with a fewer numbersof quadrupoles. In this optics, we can remove one
quadrupole family at the short straight sections. Thismay be beneficial to install new devices for beamhandlings, beam monitors or light source developments.

Ⅲ -1

Fig. 1. Tie diagram of UVSOR-III magnetic lattice.
KF and KD are quadrupole strengths.

Fig. 2. An optic whit a small emittance of 9.4 nm at
750 MeV.

Fig. 3. An optic which gives a moderately small
emittance of 13.3 nm with less numbers of quadrupoles.
[1] M Katoh, K Hayashi, et al., Nucl. Instr. Meth. A
467 (2001) 68.
[2] M Katoh, M Hosaka, et al, AIP Conf. Proc. 705(2004) 49.
[3] M Adachi, H Zen, et al., J. Phys. Conf. Ser. 425(2013) 04201.
[4] M. Katoh, M. Adachi, et al, AIP Conf. Proc. 1234
(2010) 531.
[5] M. Borland, APS LS-287 (2000).
https://www.aps.anl.gov/Accelerator-Operations-Physics/Software

35
Ⅲ01- 3 -BL1U
Ⅲ -1. Accelerators
and Instruments

BL1U

Selective Isotope 3D-CT Imaging in UVSOR-BL1U
H. Ohgaki1, K. Ali1, H. Zen1, T. Kii1, T. Hayakawa2, T. Shizuma2, H. Toyokawa3,
M. Fujimoto4, Y. Taira4 and M. Katoh4,5Institute of Advanced Energy, Kyoto University, Uji 611-0011, Japan
Tokai Quantum Beam Science Center, National Institutes for Quantum and Radiological Science andTechnology, Tokai-mura 319-1106, Japan
3
National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 3058568, Japan
4
UVSOR Synchrotron Facility, Institute for Molecular Science, Okazaki 444-8585, Japan
5
Hiroshima University, Higashi-Hiroshima 739-8511, Japan
1

2

Ⅲ -1

A Nuclear Resonance Fluorescence (NRF) method is
a powerful tool for investigating nuclear physics andisotope imaging inside the spent nuclear fuel canisters
and nuclear wastes. We have been developing an
isotope imaging technique using the NRF scattering
method in AIST [1] and transmission method in
UVSOR-III [2].
We successfully got 2D NRF-CT images by using
an LCS gamma-ray beam with two enriched isotope
targets, 206Pb (>93.3 %) and 208Pb (>97.8 %), inserted
in an aluminum holder at the beamline BL1U in
UVSOR-III in 2019 [3]. In 2020, we tried to obtain a
3D image of the same CT target. The geometry of theCT target is shown in Fig.1.
The LCS gamma-ray beam with a maximum energyof 5.528 MeV was generated by using a fiber laser(wavelength of 1,896 μm, 50 W). The gamma-ray beamwith a 10 photon·s-1·eV-1 flux density was used to excite
Jπ=1- state at 5.512 MeV of 208Pb with a 2-mm leadcollimator. The gamma-ray absorption by the CT target
was measured at 4-mm step in the horizontal direction(x= –12 to +12 mm) and 30° step in the rotation angle(θ=0° to 150°). Three vertical positions (z=3, 11, and 17mm from the holder's bottom) were taken. Two HP-Ge
detectors measured the NRF signals from the witness
target (208Pb enriched) with 100 % and 130 % relative
efficiencies. The transmission gamma-rays have beenmeasured by a 3.5” × 4” LaBr3(Ce) detector, which
gives a density distribution by the atomic absorption
process of the sample target at the same time. After
suppressing the atomic absorption process measured by
the LaBr3(Ce) detector, the NRF-CT images, which
selectively indicate the distributions of 208Pb, wereobtained. Figure 2 shows a typical one-layer CT image(z=3 mm case). By stacking 3-layer NRF-CT images, arough 3D NRF-CT image of 208Pb distribution in the CT
target was successfully obtained, as shown in the Fig. 3.

Fig. 1. Geometry of the CT target. Right figure shows
the configuration of enriched rods inserted to thealuminium cylinder shown in the left figure.

Fig. 2. NRF-CT image at z= 3 mm

Fig. 3. 3D NRF-CT image[1] N. Kikuzawa et al., Appl. Phys. Express 2 (2009)
036502.
[2] H. Zen et al., AIP Advances 9 (2019) 035101.
[3] K. Ali et al., IEEE Trans. Nucl. Sci. 67 (2020) 1976.

36
Ⅲ01- 4 -BL1U

Ⅲ -1. Accelerators and Instruments

BL1U

Elastic Scattering of Gamma-rays with Energies of 10 MeV
1

T. Hayakawa1, K. Kawase1, T. Shizuma1, R. Hajima1, J. K. Koga2, H. Zen3, T. Kii3,
H. Ohgaki3, M. Fujimoto4, Y. Taira4 and M. Katoh4,5National Institutes for Quantum and Radiological Science and Technology, Tokai-mura 319-1106, Japan
National Institutes for Quantum and Radiological Science and Technology, Kizugawa 619-0215, Japan
3
Institute of Advanced Energy, Kyoto University, Kyoto 611-0011, Japan
4
UVSOR Synchrotron Facility, Institute for Molecular Science, Okazaki 444-8585, Japan
5
Hiroshima University, Higashi-Hiroshima 739-8511, Japan2

QED theory predicted unresolved nonlinear effects
such as photon-photon interactions [1,2]. Recently,
virtual photon – virtual photon scattering with energiesof 5 TeV has been measured using a high energy
accelerator [1]. One of the photon- photon interactions
is Delbrück scattering, which is an elastic scattering of
gamma-rays. However, there was a critical problem
that one cannot calculate the scattering using only the
amplitude of Delbrück scattering due to theinterference of other elastic scattering. Koga andHayakawa [3] have presented that it is possible tomeasure selectively the amplitude of Delbrück
scattering using linearly polarized gamma-rays.
To study Delbrück scattering we have installed a
CO2 laser [4]. Here, we have installed a fiber laser witha wavelength of 1064 nm and an average power of 10
W. The pulse width is 1 ns and the pulse energy is 25
μJ. The maximum repetition is 400 kHz and can becontrolled by an external trigger. The laser Compton
scattering (LCS) gamma-rays with a maximum energyof 10 MeV were generated by interactions withelectron beams having an energy of 750 MeV stored
in UVSOR-III. To generate linearly polarized gammarays we used a linear polarized laser. We newly
developed a collimator system and detector frame. The
tungsten target with a diameter of 5 mm and a lengthof 50 mm was used. The gamma-rays scattered fromthe target were measured with two 3.5” × 4” LaBr3(Ce)scintillation detectors, which were placed at φ= 0 and
90 degrees from the linear polarization plane at θ = 90
degrees away from the gamma-ray propagation axis
(see Fig. 1). Figure 2 shows the measured energy
spectra. A broad peak is observed in an energy region
from 5–7 MeV in Fig. 2(b) but it is not observed in Fig.
2(a). This peak originates from Compton scattering ona mirror inside the beamline. The elastic scattering is
not clearly observed.

[1] ATLAS Collaboration, Nature Physcs 13 (2017)852.
[2] T. Inada, et al., Phys. Lett. B 732 (2014) 356.
[3] J. K. Koga and T. Hayakawa, Phys. Rev. Lett. 118(2017) 204801.
[4] H. Zen et al., J. Phys.: Conf. Ser. 1067 (2018)
092003.

Ⅲ -1

Fig. 1. A schematic view of the scattering experiment.
The gamma-rays scattered from the target were
measured with two LaBr3(Ce) scintillation detectors.

Fig. 2. Measured gamma-ray spectra using LaBr3(Ce)scintillation detectors. The spectrum measured at φ =0° away from the linear polarization plane (a) and thatat by φ = 90° (b).

37
Ⅲ01- 5 -BL1U
Ⅲ -1. Accelerators
and Instruments

BL1U

Improvement of Interferometer for Measuring The Coherence Length ofLight from an Undulator
A. Mano1, S. Kimura1, M. Hosaka1, T. Takashima1 and M. Katoh2,3Nagoya University, Nagoya 464-8603, Japan
Hiroshima University, Higashi-Hiroshima, 739-0046, Japan
3
UVSOR Synchrotron Facility, Institute for Molecular Science, Okazaki 444-8585, Japan
1

2

Ⅲ -1

We are experimentally studying the time domain
structure of light from an undulator so-called coherence
length, which is wave packet length emitted from asingle electron passing through the undulator.
We attempted to measure the coherence length oflight from an undulator using a Michelson-type
interferometer [1]. The light from the undulator is splitby the first beam splitter (non-polarizing type). After
split lights are folded back by the retroreflector andoverlapped again by the second beam splitter. By
moving one of the retroreflectors, a difference in the
optical path is created. The overlapping lights interferewith each other, causing fluctuation in intensity
according to the optical path difference. The intensity
fluctuation is called an interferogram. If the overlapping
light is angled, the image forms interference fringes, but
the interferogram corresponds to the intensity
fluctuation of a single point in the image. Theinterferogram is the autocorrelation of the undulator
light wave packet.
At first, we constructed an interferometer using φ20mm pedestal posts. We use 10 mm square cube typebeam splitters and right-angle prisms as retroreflectors.
This interferometry is shown in Fig.1. This opticalsystem generated a lot of stray light and was difficult toadjust. Further, this optical system had low rigidity andthe optical elements were prone to vibration. The
system was exposed, therefore it was easily affected byfluctuations in the atmosphere. The image of theinterference fringes obtained by this optical system isshown in Fig. 2. In Fig. 2. (b), the fringes are blurred,probably due to vibration. In Fig. 2. (c), the phase of thefringes is shifted, probably due to atmosphericfluctuations. Thus, the interferogram measurement
proved to be very difficult with this optical system.
We attempted to improve the interferometer. Bychanging the single-point support of the pedestal post to
multi-point support by the optical cage system, therigidity of the system has been improved and roughalignment is no longer necessary. To reduce stray light,
the beam splitter cube was replaced with a beam splitter
plate and the retroreflector was replaced with two
mirrors. Further, the use of a kinematic holder for thefolded mirror made it easier to adjust the overlay of thetwo split beams. Furthermore, by covering the areaaround the optical system, it was protected fromatmospheric fluctuations. These improvements made it
possible to obtain stable images of interference fringes.
More details on the results from the improved

interferometer will be presented in a future paper.

Fig. 1. Photo of the interferometer we first constructed.

Fig. 2. Images of interference fringe in the same
condition.

Fig. 3. Photo of the improved interferometer.
[1] S. Notsu et al., UVSOR Activity Report 2019 47(2020) 37.

38
Ⅲ01- 6 -BL2A

Ⅲ -1. Accelerators and Instruments

BL2A

Evaluation of the Robustness of Back-illuminated CMOS Sensors Against
Soft X-rays
N. Narukage

National Astronomical Observatory of Japan, Mitaka 181-8588, JapanThe solar corona is full of dynamic phenomena. They
are accompanied by interesting physical processes,
namely, magnetic reconnection, particle acceleration,
shocks, waves, flows, evaporation, heating, cooling,and so on. The understandings of these phenomena andprocesses have been progressing step-by-step with theevolution of the observation technology in EUV and Xrays from the space. But there are fundamental
questions remain unanswered, or haven’t evenaddressed so far. Our scientific objective is tounderstand underlying physics of dynamic phenomenain the solar corona, covering some of the long-standing
questions in solar physics such as particle accelerationin flares and coronal heating. In order to achieve thesescience objectives, we identify the imaging
spectroscopy (the observations with spatial, temporaland energy resolutions) in the soft X-ray range (from~0.5 keV to ~10 keV) is a powerful approach for thedetection and analysis of energetic events [1]. This
energy range contains many lines emitted from below 1
MK to beyond 10 MK plasmas plus continuum
component that reflects the electron temperature.
The soft X-ray imaging spectroscopy is realized withthe following method. We take images with a shortenough exposure to detect only single X-ray photon in
an isolated pixel area with a fine pixel Silicon sensor.
So, we can measure the energy of the X-ray photons one
by one with spatial and temporal resolutions. When weuse a high-speed soft X-ray camera that can perform thecontinuous exposure with a rate of more than several
hundred times per second, we can count the photon
energy with a rate of several 10 photons / pixel / second.
This high-speed exposure is enough to track the time
evolution of spectra generated by dynamic phenomenain the solar corona, whose lifetimes are about fromseveral ten seconds to several minutes.
For the first imaging spectroscopic observation of thesolar corona in soft X-ray range, we launched a NASA’ssounding rocket (FOXSI-3) on September 7th, 2018 andsuccessfully obtained the unprecedented data [2] using
a high-speed X-ray camera [3] with a back-illuminated
CMOS sensor [4].
Though this back-illuminated CMOS sensor has anenough photon-counting capability for the X-ray
imaging-spectroscopy as demonstrated by FOXSI-3
flight, we found that it is damaged by the incident Xrays (which themselves are the targets of detection) as
shown in Fig. 1.
For the evaluation of the robustness of the sensor
against the incident X-rays, we did the following

procedures:
1. Take dark image to monitor the dark level (biaslevel) and noise level (readout noise + dark noise).
2. Emit the monochromatic intense X-rays with
BL2A for a certain period.
3. Repeat Procedures 1 and 2 until the dark level issaturated.
We did this evaluation with three monochromatic Xrays of 1 keV, 2 keV and 4 keV, for two types of backilluminated CMOS sensors, whose difference is only
the thickness of sensitive layers. The thicknesses areabout 4μm and 10μm. Based on these evaluations, wefound that the sensor with the thicker sensitive layer cansurvive against the more incident X-ray photons. In theenergy of each monochromatic X-rays, the detectable
X-ray photon number without serious damage isroughly proportional to the absorption rate of thesensitive layer. Hence, we suspected that thepresumable damaged part is the circuit layer, which islocated behind the sensitive layer.
In our estimate based on these evaluations, more than
~15μm sensitive later is required for solar flareobservations. We plan to confirm this result using theCMOS sensor with 25μm sensitive layer in FY2021.

Fig. 1. Dark image of the CMOS damaged by X-rays.

[1] N. Narukage et al., White paper of the “soft X-ray
imaging spectroscopy”, arXiv:1706.04536 (2017).
[2] N. Narukage and S. Ishikawa, UVSOR Activity
Report 2018 46 (2019) 36.
[3] S. Ishikawa et al., Nuclear Instruments and Methods
in Physics Research Section A 912 (2018) 191.
[4] N. Narukage et al., Nuclear Instruments and Methods
in Physics Research Section A 950 (2020) 162974.

39
Ⅲ01- 7 -

Ⅲ -1

BL3U
Ⅲ -1. Accelerators
and Instruments

BL3U

Development of an Ultrathin Liquid Cell for Soft X-ray Absorption
Spectroscopy in the Low-Energy Region
2

Ⅲ -1

M. Nagasaka1,2Institute for Molecular Science, Okazaki 444-8585, JapanThe Graduate University for Advanced Studies, SOKENDAI, Okazaki 444-8585, Japan
1

Soft X-ray absorption spectroscopy (XAS) is anelement-specific method to investigate local structuresof liquids and solutions. Recently, we have developed atransmission-type liquid cell for XAS of liquid samples,
where a liquid layer is sandwiched between two Si3N4
membranes with the thickness of 100 nm and the liquid
thickness is precisely controlled by adjusting the heliumpressure around the liquid cell [1]. On the other hand,
the low-energy region below 200 eV is important forchemical research since it includes K-edges of Li and B
and L-edges of Si, P, S, and Cl. However, the soft X-ray
transmission calculation [2] predicts that soft X-rays
below 200 eV cannot transmit the present liquid cell,which consists of four Si3N4 membranes and 20 mm
optical path of He gas. Recently, we have established
the argon gas window, which is effective for thetransmission of soft X-rays from 60 to 240 eV with theremoval of high order X-rays [3]. We also found thatsoft X-rays in the low-energy region can transmit theultrathin liquid cell with the optical length of 2.6 mm.
In this study, we realize XAS in the low-energy region
by developing the ultrathin liquid cell.
Figure 1(a) shows a schematic of the XAS
measurement system including the ultrathin liquid cell.
The experiment was performed at BL3U. In theultrathin liquid cell, a liquid layer is sandwiched
between two Si3N4 membranes and is in an atmospheric
Ar condition. The soft X-ray beamline and a photodiodedetector are under ultrahigh vacuum conditions and areseparated from the atmospheric Ar chamber with Si3N4
membranes with a small window size (0.2 × 0.2 mm2).
Figure 1(b) shows photographs of the ultrathin liquidcell. In the left part, soft X-rays pass through the Si3N4
membranes settled in the center part of the liquid cell.
In the right part, the thickness of the ultrathin liquid cellbecomes 2.4 mm. Considering the thickness of theholders of small Si3N4 windows, the optical pass lengthof Ar gas is estimated to be 2.6 mm.
Figure 2 shows Cl L-edge XAS spectrum of 2 M LiClsolution by using the ultrathin liquid cell. The spectrum
shows two peaks with the positions of 203 eV and 208
eV. We have also obtained Li K-edge XAS spectrum of
2 M LiCl solution although the signal-to-noise ratio is
not sufficient due to the low photon flux at the Li Kedge. In the present study, we have confirmed theeffectiveness of the ultrathin liquid cell for XAS in the
low-energy region. However, the photon flux is still low
due to the strong absorption of Si3N4 membranes at the
Si L-edge (100 eV). It is difficult to optimize theabsorbance of solute LiCl peaks with the increase of theliquid thickness. In the future, we will prepare polymer
membranes that consist of no Si atoms to obtain highphoton flux of transmitted soft X-rays and measure
XAS spectra in the low-energy region with a goodsignal-to-noise ratio.

Fig. 1. (a) A schematic of the XAS measurement systemin the low-energy region with the ultrathin liquid cell. (b)Photographs of the ultrathin liquid cell.

Fig. 2. Cl L-edge XAS of 2 M LiCl solution.

[1] M. Nagasaka, H. Yuzawa and N. Kosugi, Anal. Sci.
36 (2020) 95.
[2] C. T. Chantler, J. Phys. Chem. Ref. Data 29 (2000)
597.
[3] M. Nagasaka, J. Synchrotron Rad. 27 (2020) 959.

40
Ⅲ01- 8 -BL3B

Ⅲ -1. Accelerators and Instruments

BL3B

Development of Ion Time-of-Mass Spectrometer at UVSOR BL3B
H. Iwayama 1,2 and T. Horigome1

UVSOR Synchrotron Facility, Institute for Molecular Science, Okazaki 444-8585, Japan
School of Physical Sciences, The Graduate University for Advanced Studies, SOKENDAI, Okazaki 444-8585, Japan
1

2

Halogenated alkanes are used as flame retardants,
fire extinguishants and refrigerant gases. While they
are useful and widely used in commerce, they havealso been shown to be serious pollutants and toxins. In
particular, the chlorofluorocarbons have been shown tolead to ozone depletion. Photolysis and the reactions ofthese substances with hydroxyl radical, the mainoxidizing agent of the troposphere, derived from thephotolysis of ozone, determine their life-time in theatmosphere. In the stratosphere they interact with
VUV light and produce halogen atoms which
contribute to the ozone depletion process.
Photodissociation and photoionization channels arevery interesting since difference fragmentation
channels can lead to different radical and/or cations
which can play a role in several fields, fromatmospheric chemistry to etching and plasma assisted
industrial process. In this work, we developed iontime-of-flight mass spectrometer at BL3B for
photochemistry of halogenated alkanes in UV andVUV region.
The experiment was performed at UVSOR BL3B,
where we use intense synchrotron light from visible to
EUV regions. A schematic view of our experimental
setup is shown in Fig. 1. The sample gas jet isgenerated from the capillary nozzle and irradiated by
VUV light between ion and electron extract meshes.
While a photoelectron is detected by the electron MCP
detector, an ion is introduced to ion time-of-flight mass
spectrometer. Detection signals of electron and ion areused as start and stop signal for time-of-flight
spectrometer, respectively. The sample is R22 gases(CHF2Cl).
Figure 2 shows ion time-of-flight mass spectra for
CH2FCl molecules at photon energies of 15, 20 and 30
eV. At the photon energy of 15 eV, we find that dominantfragment ions are CHF2+. This means that major
photodissociation is CHF2Cl + hv (15eV)  CHF2+ +Cl and generate a Cl radical. Here we note that relative
abundance of parent molecular ions, CHF2Cl+, is very
low. Our results suggest that the C-Cl bond is easily
broken by VUV photon absorptions. By increasing
photon energies, we also find smaller fragment ionssuch as CF+, Cl+ and CH+ and H+ ions. Since we alsomeasured these ion yields as a function of photon
energies, corresponding appearance energies of eachfragment ions will be deduced. Now we analyzed theseresults in details.

Ⅲ -1

Fig. 1. Schematic view of our ion time-of-flight
spectrometer.

Fig. 2. Ion time-of-flight mass spectra for CHF2Cl
molecules at photon energies of 15, 20 and 30 eV.

41
Ⅲ01- 9 -BL4U
Ⅲ -1. Accelerators
and Instruments

BL4U

Study of STXM with IR Laser Optics Part I.
‒ In-Situ Removal of Organic Contamination from Carbon Nanotube ‒2

Ⅲ -1

H. Yuzawa1 and T. Ohigashi1,2

UVSOR Synchrotron Facility, Institute for Molecular Science, Okazaki 444-8585, Japan
School of Physical Sciences, The Graduate University for Advanced Studies, SOKENDAI, Okazaki 444-8585, Japan
1

Scanning Transmission X-ray Microscope (STXM)
gives two-dimensional X-ray absorption spectroscopy(XAS) spectra of sample with ca. 50 nm spatial
resolution, which is powerful to get the distribution ofchemical state. However, the measurement immediately
after heating sample in the STXM chamber is difficult
because the focal length of a Fresnel zone plate (FZP)
in soft X-ray region is short as shown in Fig. 1a. Main
problems of this measurement are harmful influences
for the optical elements, and large sample drift bythermal vibration. In the present study, we have carriedout heating the sample by using an IR laser diode fromoutside of the chamber to reduce the remaining thermal
source in there. As a test sample for heating, carbon
nanotube (CNT) has been applied to in-situ removal of
its organic contaminations, based on the user’s request.
Figure 1b shows the picture of experimental set up
for heating the sample. Diverging light of themultimode IR laser diode (3 W, 940 nm) is collimatedwith two cylindrical plane-convex lenses (f = 5 and 10cm) and is focused to sample inside the STXM
chamber with a spherical plane-convex lens (f = 50
cm).
CNT (NanoIntegris Inc., IsoNanotube-S) was usedas the sample, whose contaminations are iodixanol(Fig. 2) and some surfactant (its structure is not open)[1]. 0.5 mg of the CNT was dispersed into water (40ml) by using an ultrasonic homogenizer, then thesuspension (3 μl) was dropped and dried on a Si3N4
membrane (window size, 0.5 × 0.5 mm2). STXM
measurements in C K-edge of the CNT were carriedout after heating the sample at ca. 280 °C undervacuum for 15 min. During the heating of the sample,
the sample and a detector stage were moved to 7 cm
backward from its measuring position.
Figure 3a shows one of the STXM images ofaggregated CNT in C K-edge XAS measurement. The
drift of sample is at most 200 nm during themeasurement. Since this value is enough small forbasic measurements in BL4U, the harmful influence ofthe thermal source is successfully reduced by using the
IR laser diode. Figure 3b shows the corresponding C
K-edge XAS spectra. The spectral shape is graduallychanged with increasing the integrated irradiation timeof the IR laser. All the measuring region of CNT in Fig.
3a converges to the reported spectrum of it [2] for 75
min (Fig. 3b, blue line).

Fig. 1. (a) Side view of optical system around thesample in STXM chamber. Dotted-line arrows show
the moving direction during measurements. (b) Topview of optical system for heating the sample by IR
laser diode.
OH

HO
OH
HO

H
N

H
N

O

I

O

I

I

I

N

N
OH
O
O

OH

H
N

O

OH
I

I

H
N

OH
OH

O

Fig. 2. Structural formula of iodixanol.

Fig. 3. (a) STXM image (based on absorbance [= ln(I/I0)]) of aggregated CNT at 290 eV. I0 was taken
form green region. (b) C K-edge XAS spectra ofyellowish green region in (a), measured every 15 min
irradiation of the IR laser.
[1] Homepage of NanoIntegris Inc.
[2] S. Banerjee et al., J. Phys. Chem. B 109 (2005) 8489.

42
Ⅲ01- 10 -BL4U

Ⅲ -1. Accelerators and Instruments

BL4U

Study of STXM with IR Laser Optics Part II.
‒ In-Situ Observation of Mn2O3 Calcination ‒2

H. Yuzawa1 and T. Ohigashi1,2

UVSOR Synchrotron Facility, Institute for Molecular Science, Okazaki 444-8585, Japan
School of Physical Sciences, The Graduate University for Advanced Studies, SOKENDAI, Okazaki 444-8585, Japan
1

Defect formation in solid is an attractive research
field in such as material chemistry and catalytic
chemistry. For example, the defect in the photocatalyst
influences photocatalytic activity and product selectivity[1]. Thus, the observation of defect formation isimportant under various conditions (e.g., temperatureand pressure) of sample.
Scanning Transmission X-ray Microscopy (STXM)
is powerful analytical method to get the twodimensional distribution of chemical state. In theprevious page of this activity report [2], we reported
the thermal treatment of the CNT to remove theorganic contaminations by using the IR laser diode. In
the present study, we have applied this system to theobservation of defect formation in Mn2O3 sample,
which is one of the famous oxide catalysts.
Experiments were performed in the BL4U connectedwith the optical system of IR laser diode (see the Fig.
1(b) of [2]). 10 mg of Mn2O3 (Wako Pure Chemical
Industries, Ltd.) was dispersed into 50 ml water withvigorous stirring, then the suspension (3 μl) was dropped
and dried on a Si3N4 membrane (window size, 1×1
mm2). STXM measurements in O K-edge and Mn Ledge were carried out after heating the sample at ca.
300 °C under vacuum for 10 s. During the heating of
the sample, the sample and a detector stage were moved
to 7 cm backward from its measuring position.
Figure 1(a) shows the representative STXM imageof aggregated Mn2O3 particles in Mn L-edge XAS
measurement before the heating. Through the entire
measurement (10 cycles of the IR laser radiation (100s) and 11 cycles of STXM measurements for O K-edge(5.5 h) and Mn L-edge (6.5 h)), the sample shape wasalmost the same as that in Fig.1(a). On the other hand,in Figs. 1(b) and 1(c), both O K-edge and Mn L-edge
XAS are varied with increasing the integrated heatingtime until 50 s, and then almost the constant spectra
are obtained from 60 to 100 s. The finally obtained
spectra of O K-edge and Mn L-edge are similar to
those of Mn3O4 [3]. Thus, this spectral change
indicates that the defect of oxygen is produced in
Mn2O3 and the valence of Mn partially changed from
III to II during the heating.
In another run of measurement, the influence of soft
X-ray radiation on the state of Mn2O3 without heating
was evaluated (Figure is not shown). As the result of 3
cycles of STXM measurement in O K-edge and Mn Ledge under vacuum at room temperature, the sample
shape and the spectra did not change. This result
indicates that any change of state in Figs. 1(b) and 1(c)is not derived from soft X-ray radiation but the heatingof sample.

Fig. 1. (a) STXM image (based on absorbance [= ln(I/I0)]) of aggregated Mn2O3 particles at 640 eV. I0
was taken form green region. (b) O K-edge XAS
spectra and (c) Mn L-edge XAS spectra of the blue
region of (a), measured every 10 s IR laser radiation.

[1] S. A. Rawool et al., Chem. Sci. 12 (2021) 4267.
[2] H. Yuzawa and T. Ohigashi, UVSOR Activity Report2020 48 (2021) 42.
[3] B. Gilbert et al., J. Phys. Chem. A 107 (2003) 2839.

43
Ⅲ01- 11 -

Ⅲ -1

BL4B
Ⅲ -1. Accelerators
and Instruments

BL4B

Development of High Efficiency Liquid Cell in Total Electron Yield Using
Atomically-thin Graphene
I. Mitsuishi 1, K. Kashiwakura1, Y. Niwa1, T. Ogawa1, Y. Tawara1, R. Kitaura2,
P. Solís-Fernández3, K. Kawahara3, H. Ago3, T. Taniguchi4, K. Nomoto4, H. Kodaka4,
T. Horigome5, E. Nakamura5, H. Iwayama5, M. Nagasaka5 and K. Tanaka51

Ⅲ -1

Graduate School of Science, Division of Particle and Astrophysical Science, Nagoya University,
Nagoya 464-8602, Japan2
Department of Chemistry, Nagoya University, Nagoya 464-8602, Japan3
Global Innovation Center, Kyushu University, Kasuga, 816-8580, Japan
4
Optical Measurement Technology Development Department, R&D Division, USHIO INC.,
Yokohama 225-0004, Japan
5
UVSOR Synchrotron Facility, Institute for Molecular Science, Okazaki 444-8585, Japan

X-rays are a powerful probe to investigate material
properties through, e.g., X-ray absorption spectroscopy(XAS) which can reveal local atomic and electronic
states of oxygen, carbon, etc.. Among the XAS methods
for liquid, total electron yield is preferably utilized insome cases because short electron escape depth in thismethod makes it possible to examine atomic andelectron states of liquid surface and solid- liquidinterfaces. In order to realize high efficiency
measurements through the total electron yield method,high efficiency films with high electron transmission are
a key and therefore have been strongly desired.
To construct our original device for the total electron
yield measurements, we propose to utilize graphene
which is atomically thin and has high electrontransmission [1]. As the first step, we tried to establish
our original experimental setup to verify our idea asshown in Fig. 1. As a preliminary experiment, liquidwater was sandwiched by two silicon nitride windows
with apertures of 0.5 x 0.5 and 0.2 x 0.2 mm instead ofgraphene. We successfully detected transmitted lights
and photoelectrons as shown in Figs. 2 and 3,
respectively.

Fig. 2. Transmittance as a function of energy for thesilicon nitride windows with aperture areas of 0.5 mm(black) and 0.2 mm (red).

Fig. 3. Photoelectron count around the nitrogen edge
structure.

Fig. 1. Our original experimental setup for the highefficient total electron yield method.

[1] G. Hassink, R. Wanke, I. Rastegar, W. Braun, C.
Stephanos, P. Herlinger, J. H. Smet and J. Mannhart,
APL Materials 3 (2015).

44
Ⅲ01- 12 -BL5B

Ⅲ -1. Accelerators and Instruments

BL5B

Development of Multilayer Coated Mirror for the Next Jupiter Mission
1

L. Huiyang1, Y. Jie1, S. Nishimura1, K. Yoshioka1,2 and I. Yoshikawa1,2

Department of Complexity Science and Engineering, Graduate School of Frontier Sciences, The University ofTokyo, Kashiwa 277-8561, Japan2
Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo,
Tokyo 113-0033, Japan

Observation of solar planets in the extreme ultraviolet(EUV) spectral region is important to study dynamics
of their magnetospheres. Recently, extension to shorter
wavelength (XUV: x-ray and ultraviolet) is highly
desired. However, there are still technical difficulties
due to lack of techniques for collection of photons.
Multilayer coated mirrors reflecting the XUV radiation
at the normal incidence have potentials to overcome thedifficulties [1].
Yoshikawa et al. (2005) showed the reflectivities of
their newly developed multilayer coatings, consisting of
40 pairs of Mg and SiC [2]. The decrease in reflectivity
was reported in high temperature (~55 °C) and highhumidity (~65 %) environment. For science missions
generally, science instruments have to survive hightemperature and humidity environments. Therefore, weshoulddeveloprobustinstruments
againstenvironmental changes.
The measurement setup was illustrated in Figure 1.
The B4C/Mg-Si mirror was fixed on a L-shaped jig, andthe L-shaped jig was mounted on the stage. Parallel
movement by x,y motor and rotation by θ motor are
possible.
The reflectivity is measured each 0.1 nm step from25 nm to 35 nm. Figure 2 shows the reflectivity at
different incident angles of the wavelength scan
experiment before conducting the environmental test.
Figure 3 shows the reflectivity of the wavelength scan
experiment after conducting the environmental test. We
conducted the environmental test in high temperature(50 °C) for 24 hours.
It can be seen from Fig. 2 that when the incident angle
is 15 degrees and the wavelength is 31.6 nm, thereflectivity reaches its maximum, which is close to 30 %.
On the other hand, Fig. 3 shows that after theenvironmental test, when the incident angle is 25
degrees and the wavelength is 29.2 nm, the reflectivity
reaches its maximum value of 19 %, which is 2.4 nm
shorter than the result before the environmental test.

[1] D.G. Stearns et al., Multilayer mirror technology
for soft-xray projection lithography, Appl. Opt. 32(1993) 6952.
[2] Yoshikawa et al., Characteristics of SiC/Mg multilayer
mirrors, Optics for EUV, X-Ray, and Gamma-Ray
Astronomy II. 59001A (2005).

Ⅲ -1

Fig. 1. Photo of the measurement setup.

Fig. 2. Fig. 2. Reflectivity of B4C/Mg-Si multilayer
mirror in a wavelength region 25-35 nm before
conducting the environmental test.

Fig. 3. Reflectivity of B4C/Mg-Si multilayer mirror
in a wavelength region 25-35 nm after conducting theenvironmental test.

45
Ⅲ01- 13 -BL5B
Ⅲ -1. Accelerators
and Instruments

BL5B

Performance Evaluation of Filaments used in the Hydrogen Absorption Cell
M. Kuwabara1, K. Yoshioka2, M. Taguchi3, Y. Suzuki4, S. Nishimura4 and T. Kosugi2
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency,
Sagamihara 252-5210, Japan2
Department of Complexity Science and Engineering, Graduate School of Frontier Sciences,
The University of Tokyo, Kashiwa 277-8561, Japan
3
College of Science, Rikkyo University, Tokyo 171-8501, Japan
4
Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo,
Tokyo 113-0033, Japan1

In the planetary exosphere, hydrogen atoms
resonantly scatter the solar hydrogen Lyman-alpharadiation (121.567 nm) and form the hydrogen corona.
Imaging observation of this emission provide us toobtain the spatial structure because of the dependency
of its brightness on the number density of the hydrogenatoms.
An absorption cell technique is an efficient tool forthe density and temperature measurements for the
exospheric hydrogen atoms by remotely. Additionally,
the absorption cell technique has some advantages overother instruments in terms of mass, size, and simplicity.
Therefore, the absorption cell technique is suitable for
future planetary exploration with small size spacecraft.
See Kuwabara et al. [2018] for details on the principleof the absorption cell technique [1].
The absorptance of hydrogen Lyman-alpha radiation
depends on the number of hydrogen atoms along theoptical path in the absorption cell. The dissociation rateof hydrogen molecules depends on the surface area andtemperature of the filament. In this experiment,
therefore, we evaluated absorption performances of two
filaments with different shapes by using the SOR beamwith high intensity and stability. Table 1 shows the
specifications of the filaments.
Figure 1 shows the configuration of the experiment.
A hydrogen absorption cell imager consists of anabsorption cell, MgF2 band-pass filter, and photon
detector. An assembly of microchannel plates (MCPs)
and a resistive anode encoder (RAE) was used as thephoton detector. The dependence of the absorptance ofhydrogen Lyman-alpha radiation on the power
consumption (i.e. filament temperature) was measured
using each filament.
The result is shown in Fig. 2. The absorptance ofhydrogen Lyman-alpha radiation when using theX10731 filament is higher than when using the X10478
filament. This is probably due to the large surface areaof the X10731 filament. For the next step, further
investigations such as long-term stability of absorption
and durability of the filaments are required.

Table 1. Specifications of filaments.
Cross-section
Coil length
X10478
Φ 48 μm
3 mm
X1073111 x 61 μm
3 mm

Fig. 1. Configuration of the experiment.

0.05
Absorptance (peak)

Ⅲ -1

0.04

X10478
X10731

0.03
0.02
0.01
0
0

0.5

1

1.5
2
Power [W]2.5

3

Fig. 2. Absorptance of the absorption cell.

[1] M. Kuwabara et al., Review of Scientific Instruments
89 (2018) 023111.

46
Ⅲ01- 14 -BL5B

Ⅲ -1. Accelerators and Instruments

BL5B

Trial to Mitigate Photon-Energy Drift of BL5B
H. Zen1, E. Nakamura2, K. Hayashi2 and K. Tanaka2,3Institute of Advanced Energy, Kyoto University, Uji 611-0011, JapanUVSOR Synchrotron Facility, Institute for Molecular Science, Okazaki 444-8585, Japan3
School of Physical Sciences, The Graduate University for Advanced Studies, SOKENDAI, Okazaki 444-8585, Japan
1

2

The variation of the photon beam properties, such as
beam position, photon energy, and so on, during user
operation in the beamline is a big issue in synchrotron
radiation (SR) facilities. A photon-energy drift at BL5B
has been observed during user experiments [1]. We havestarted a detailed investigation of the source of thephoton-energy drift. In 2019, we found that the M0
mirror, which is water cooled but directly illuminatedwith SR, in the beamline is not the major source of theenergy drift but the M1 mirror could be the major sourceof that [2]. At that time, temperature of the M1 mirror
holder was higher than the M1 mirror. This implied that
the SR which was not reflected by the M0 mirror
directly hit on the M1 mirror holder. At the same time,
we found the correlation between the photon-energy
drift and the temperature of the M1 mirror holder. We
considered that the large temperature rise of the M1
mirror holder and heat induced deformation of it was
the major source of the photon-energy drift.
In this fiscal year, a metallic mask was installed to
avoid the SR directly hitting on the M1 mirror holder asshown in Fig. 1 left. In order to monitor the temperatureof the mirror and mirror holder, four thermocouples(TCs) have been installed. For temperature stabilizationof the mirror, a heater is installed at the center of themirror. At first, effect of the mask was examined. The
temperature variations of the M1 mirror and mirror
holder with the mask are shown in Fig. 1 right. As theresult, the temperature increased up to 35 deg. C in 36
hours with the mask. This was much smaller than thetemperature rise without mask (up to 73 deg. C) [2]. The
temperature rise of the mirror holder was greatly
suppressed.
The photon-energy drift after the monochromator of
BL5B was continuously monitored by using theabsorption edge of an aluminum filter. Results areshown in Fig. 2 (a). The temperature of the mirror was
stabilized by the feedback control of the heater power
supply according to the temperature of the mirror center.
Two temperature targets were examined in this test. One
was the 60 deg. C, which was slightly higher than thesaturated temperature of the mirror. The other was 80
deg. C, which was 20 deg. C higher than the saturated
temperature of the mirror. Unfortunately, the photonenergy drift cannot be suppressed by installation of themask and the temperature feedback of the M1 mirror.
However, the photon-energy and the temperature of themirror holder have same periodic variation and drift
when the target temperature was set to 80 deg. C as one
can see in Fig. 2 (b). This implies that the major sourceof the photon-energy drift is M1 mirror holder and not

M1 mirror itself.
To suppress the photon-energy drift of BL5B,
temperature measurement points of M1 mirror holder
should be increased and the most critical point must be
found and temperature of the point must be stabilized.

Fig. 1. (left) Photo of the M1 mirror and mirror holder
with the mask, thermocouples (TCs) and a heater.
(right) Temperature evolution during a SR irradiationfor 36 hours with the M1 mask.

(a)

(b)
Fig. 2. (a) Measured photon-energy drift withtemperature stabilization of M1 mirror. Up to 15:30,
the target temperature of the feedback was 60 deg. C.
From 18:00, the target temperature was 80 deg. C.
(b) Closed up of 19-22 hour for SR wavelength andtemperature of the mirror holder.
[1] K. Hayashi, UVSOR Activity Report 2011 39 (2012)121.
[2] H. Zen, UVSOR Activity Report 2019 47 (2020) 42.

47
Ⅲ01- 15 -Ⅲ -1

UVSOR User 4