Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Endo, Shunsuke; Okudaira, Takuya*
Hamon, 33(2), p.68 - 72, 2023/05
no abstracts in English
Okudaira, Takuya*; Tani, Yuika*; Endo, Shunsuke; Doskow, J.*; Fujioka, Hiroyuki*; Hirota, Katsuya*; Kameda, Kento*; Kimura, Atsushi; Kitaguchi, Masaaki*; Luxnat, M.*; et al.
Physical Review C, 107(5), p.054602_1 - 054602_7, 2023/05
Times Cited Count:0 Percentile:0.03(Physics, Nuclear)no abstracts in English
Endo, Shunsuke; Okudaira, Takuya*; Abe, Ryota*; Fujioka, Hiroyuki*; Hirota, Katsuya*; Kimura, Atsushi; Kitaguchi, Masaaki*; Oku, Takayuki; Sakai, Kenji; Shima, Tatsushi*; et al.
Physical Review C, 106(6), p.064601_1 - 064601_7, 2022/12
Times Cited Count:1 Percentile:39.66(Physics, Nuclear)no abstracts in English
Endo, Shunsuke; Shizuma, Toshiyuki*; Zen, H.*; Taira, Yoshitaka*; Omer, M.; Kawamura, Shiori*; Abe, Ryota*; Okudaira, Takuya*; Kitaguchi, Masaaki*; Shimizu, Hirohiko*
UVSOR-49, P. 38, 2022/08
Koga, Jun*; Takada, Shusuke*; Endo, Shunsuke; Fujioka, Hiroyuki*; Hirota, Katsuya*; Ishizaki, Kohei*; Kimura, Atsushi; Kitaguchi, Masaaki*; Niinomi, Yudai*; Okudaira, Takuya*; et al.
Physical Review C, 105(5), p.054615_1 - 054615_5, 2022/05
Times Cited Count:2 Percentile:61.15(Physics, Nuclear)no abstracts in English
Okudaira, Takuya*; Endo, Shunsuke; Fujioka, Hiroyuki*; Hirota, Katsuya*; Ishizaki, Kohei*; Kimura, Atsushi; Kitaguchi, Masaaki*; Koga, Jun*; Niinomi, Yudai*; Sakai, Kenji; et al.
Physical Review C, 104(1), p.014601_1 - 014601_6, 2021/07
Times Cited Count:3 Percentile:52.17(Physics, Nuclear)Okudaira, Takuya; Ueda, Yuki; Hiroi, Kosuke; Motokawa, Ryuhei; Inamura, Yasuhiro; Takata, Shinichi; Oku, Takayuki; Suzuki, Junichi*; Takahashi, Shingo*; Endo, Hitoshi*; et al.
Journal of Applied Crystallography, 54(2), p.548 - 556, 2021/04
Times Cited Count:1 Percentile:20.14(Chemistry, Multidisciplinary)Neutron polarization analysis (NPA) for small-angle neutron scattering (SANS) experiments using a pulsed neutron source was successfully achieved by applying a He spin filter as a spin analyzer for the scattered neutrons. The
He spin filter covers a sufficient solid angle for performing SANS experiments, and the relaxation time of the
He polarization is sufficient for continuous use over a few days, thus reaching the typical duration required for a complete set of SANS experiments. Although accurate evaluation of the incoherent neutron scattering, which is predominantly attributable to hydrogen atoms in samples, is practically difficult using calculations based on the sample elemental composition, the developed NPA approach with consideration of the influence of multiple neutron scattering enabled reliable decomposition of the SANS intensity distribution into the coherent and incoherent scattering components. To date, NPA has not been well established as a standard technique for SANS experiments at pulsed neutron sources. This work is anticipated to greatly contribute to the accurate determination of the coherent neutron scattering component for scatterers in various types of organic sample systems in SANS experiments at J-PARC.
Sakai, Kenji; Oku, Takayuki; Okudaira, Takuya; Kai, Tetsuya; Harada, Masahide; Hiroi, Kosuke; Hayashida, Hirotoshi*; Kakurai, Kazuhisa*; Shimizu, Hirohiko*; Hirota, Katsuya*; et al.
JPS Conference Proceedings (Internet), 33, p.011116_1 - 011116_6, 2021/03
In neutron fundamental physics, study of correlation term of a neutron spin
and a target nuclear spin
is important because
term interferes to parity non-conserving (PNC) and time reversal non-conserving terms. For this study, a xenon (Xe) is an interesting nucleus because it has been observed an enhancement of PNC effect around neutron resonance peaks, and polarizes up to
by using a spin exchange optical pumping (SEOP) method. We would plan to develop a polarized Xe gas target with a compact in-situ SEOP system, and to study
term by utilizing epithermal neutron beams supplied from a high intense pulsed spallation neutron source. As the first step, we attempted to measure neutron polarizing ability caused by
term at a 9.6 eV s-wave resonance peak of
Xe at BL10 in MLF, by detecting change
of ratio between neutron transmissions with the polarized and unpolarized Xe target. After demonstrating that our apparatus could detect small change (
) of neutron transmissions caused by Doppler broadening effect, a signified value of
has been obtained as preliminary results. For analyzing the obtained
in detail, we are improving our nuclear magnetic resonance and electron paramagnetic resonance systems for evaluating Xe polarization independently of neutron beams.
Okudaira, Takuya; Oku, Takayuki; Ino, Takashi*; Hayashida, Hirotoshi*; Kira, Hiroshi*; Sakai, Kenji; Hiroi, Kosuke; Takahashi, Shingo*; Aizawa, Kazuya; Endo, Hitoshi*; et al.
Nuclear Instruments and Methods in Physics Research A, 977, p.164301_1 - 164301_8, 2020/10
Times Cited Count:9 Percentile:82.12(Instruments & Instrumentation)Yamamoto, Tomoki*; Okudaira, Takuya; Endo, Shunsuke; Fujioka, Hiroyuki*; Hirota, Katsuya*; Ino, Takashi*; Ishizaki, Kohei*; Kimura, Atsushi; Kitaguchi, Masaaki*; Koga, Jun*; et al.
Physical Review C, 101(6), p.064624_1 - 064624_8, 2020/06
Times Cited Count:8 Percentile:73.04(Physics, Nuclear)Okudaira, Takuya; Shimizu, Hirohiko*; Kitaguchi, Masaaki*; Hirota, Katsuya*; Haddock, C. C.*; Ito, Ikuya*; Yamamoto, Tomoki*; Endo, Shunsuke*; Ishizaki, Kohei*; Sato, Takumi*; et al.
EPJ Web of Conferences, 219, p.09001_1 - 09001_6, 2019/12
Parity violating effects enhanced by up to 10 times have been observed in several neutron induced compound nuclei. There is a theoretical prediction that time reversal (T) violating effects can also be enhanced in these nuclei implying that T-violation can be searched for by making very sensitive measurements. However, the enhancement factor has not yet been measured in all nuclei. The angular distribution of the (n,
) reaction was measured with
La by using a germanium detector assembly at J-PARC, and the enhancement factor was obtained. From the result, the measurement time to achieve the most sensitive T-violation search was estimated as 1.4 days, and a 40% polarized
La target and a 70% polarized
He spin filter whose thickness is 70 atm
cm are needed. Therefore high quality
He spin filter is developed in JAEA. The measurement result of the (n,
) reaction at J-PARC and the development status of the
He spin filter will be presented.
Okudaira, Takuya; Oku, Takayuki; Sakai, Kenji; Ino, Takashi*; Hayashida, Hirotoshi*; Hiroi, Kosuke; Shinohara, Takenao; Kakurai, Kazuhisa*; Aizawa, Kazuya; Shimizu, Hirohiko*; et al.
Proceedings of Science (Internet), 356, p.029_1 - 029_5, 2019/12
The technology development section carries out the development of the neutron polarization device: He Spin Filter. It is often used for the fundamental physics region. In order to explain the matter-dominated universe, a time reversal violation is necessary and searches for new physics are conducted in the world. The T-violation search using a polarized neutron beam is planned at J-PARC. A large
He spin filter is needed to polarize high energy neutrons for the experiment and is developed in JAEA. Recently, we developed the accurate measurement system to evaluate the polarization of
He and a vacuum system to make the
He spin filter, and large
He spin filters for epi-thermal neutron was made using the system. The current status of the development of the
He spin filter will be talked.
Okudaira, Takuya*; Takada, Shusuke*; Hirota, Katsuya*; Kimura, Atsushi; Kitaguchi, Masaaki*; Koga, Jun*; Nagamoto, Kosuke*; Nakao, Taro*; Okada, Anju*; Sakai, Kenji; et al.
Physical Review C, 97(3), p.034622_1 - 034622_15, 2018/03
Times Cited Count:11 Percentile:69.99(Physics, Nuclear)Takada, Shusuke*; Okudaira, Takuya*; Goto, Fumiya*; Hirota, Katsuya*; Kimura, Atsushi; Kitaguchi, Masaaki*; Koga, Jun*; Nakao, Taro*; Sakai, Kenji; Shimizu, Hirohiko*; et al.
Journal of Instrumentation (Internet), 13(2), p.P02018_1 - P02018_21, 2018/02
Times Cited Count:6 Percentile:32.42(Instruments & Instrumentation)Oku, Takayuki; Sakai, Kenji; Hiroi, Kosuke; Watanabe, Masao; Shinohara, Takenao; Aizawa, Kazuya; Kakurai, Kazuhisa; Kira, Hiroshi*; Hayashida, Hirotoshi*; Kiriyama, Koji*; et al.
no journal, ,
We have been developing a He neutron spin filter for applicaion at J-PARC MLF. The
He neutron spin filter is avairable for neutrons in a wide energy range, and is also effective for a divergent neutron beam. Therefore, it is very useful in the neutron scattering experiment. So far, we have devleoped a compact laser optics with a volume holographic grating (VHG) elements, and have constructed an on-beam SEOP based
He neutron spin filter. The olarization analysis tests were performed with the
He neutron spin filter at several neutron beamlines for the sans, reflectivity and neutron imaging experiments. To extend the application range of the
He neutron spin filter at J-PARC MLF, we plan to develop larger saize cells, higher power laser for the SEOP, and prepare working area for the filter inside the MLF experimental hall.
Oku, Takayuki; Sakai, Kenji; Hiroi, Kosuke; Watanabe, Masao; Shinohara, Takenao; Aizawa, Kazuya; Kakurai, Kazuhisa*; Kira, Hiroshi*; Hayashida, Hirotoshi*; Kiriyama, Koji*; et al.
no journal, ,
We have been developing a He neutron spin filter for application at J-PARC MLF. The
He neutron spin filter is available for neutrons in a wide energy range, and is also effective for a divergent neutron beam. Therefore, it is very useful in the neutron scattering experiment. So far, we have developed a compact laser optics with a volume holographic grating (VHG) elements, and have constructed an on-beam SEOP based
He neutron spin filter. The polarization analysis tests were performed with the
He neutron spin filter at several neutron beamlines for the sans, reflectivity and neutron imaging experiments. To extend the application range of the
He neutron spin filter at J-PARC MLF, we plan to develop larger size cells, higher power laser for the SEOP, and prepare working area for the filter inside the MLF experimental hall.
Sakai, Kenji; Oku, Takayuki; Harada, Masahide; Kai, Tetsuya; Hiroi, Kosuke; Hayashida, Hirotoshi*; Kira, Hiroshi*; Shimizu, Hirohiko*; Hirota, Katsuya*; Okudaira, Takuya*; et al.
no journal, ,
no abstracts in English
Oku, Takayuki; Kira, Hiroshi*; Hayashida, Hirotoshi*; Sakai, Kenji; Hiroi, Kosuke; Okudaira, Takuya; Ino, Takashi*; Shinohara, Takenao; Suzuki, Junichi*; Kakurai, Kazuhisa*; et al.
no journal, ,
We performed demonstrative experiments using the He-NSF at small-angle scattering (BL15 TAIKAN), reflection (BL17 SHARAKU) and imaging instrument (BL22 RADEN) of J-PARC MLF, and got reasonable results. Then, we have performed a demonstrative study of polarized-neutron single-crystal diffraction measurement at BL18 (SENJU). The sample was a single crystal Fe. As the result, expected flipping ratios of Bragg beaks were not observed. Therefore, we have performed a depolarization experiment of neutrons transmitted through the sample, and found out neutron severe depolarization occurred in the sample which was almost magnetically saturated under an applied magnetic field of 4.2 kG. In this paper, we will show the experimental results of the depolarization experiment of neutrons transmitted through the single crystal Fe and discuss them.
Oku, Takayuki; Watanabe, Masao; Sakaguchi, Yoshifumi*; Kawamura, Seiko; Takahashi, Ryuta*; Yamauchi, Yasuhiro*; Nakamura, Masatoshi*; Ishikado, Motoyuki*; Ouchi, Keiichi*; Arima, Hiroshi*; et al.
no journal, ,
Sample environment team at the Materials and Life Science Experimental Facility in J-PARC has worked on development and operation of cryogenics, magnets, high temperature, high pressure, soft matter related items and special environment including pulsed magnets, light irradiators and He-3 spin filters. In the talk, our status is presented, and issues are addressed.
Okudaira, Takuya
no journal, ,
The technology development section carries out the development of the neutron polarization device. Polazied neutrons are used frequently in the experiment of the particle physics. Therefore. it is necessary to cooperate with the scientists in particle physics for further developments. The matter-dominated universe cannot be explained by the standard model, and searches for new physics are carried out in the world. One of the ways is a measurement of symmetry violation using polarized neutrons and nuclei. For example, experiments to measure parity violation using the polarized neutrons and light nuclei are conducted to search for the unknown physics in quark-quark interaction. The unknown time reversal violation can be enhanced in La(n, ) with polarized neutrons, and the fundamental study to search for T-violation is ongoing using MLF. We will present the overview of the experiments for symmetry violation using polarized neutrons and the neutron polarization device.