Circular polarization measurement of -rays emitted from S(n,)S reaction with polarized neutrons

Endo, Shunsuke; Fujioka, Hiroyuki*; Ide, Ikuo*; Iinuma, Masataka*; Iwamoto, Nobuyuki; Iwamoto, Osamu; Kameda, Kento*; Kawamura, Shiori*; Kimura, Atsushi; Kitaguchi, Masaaki*; et al.

EPJ Web of Conferences, 329, p.05003_1 - 05003_3, 2025/06

https://doi.org/10.1051/epjconf/202532905003

no abstracts in English

Circular polarization measurement for individual gamma rays in capture reactions with intense pulsed neutrons

Endo, Shunsuke; Abe, Ryota*; Fujioka, Hiroyuki*; Ino, Takashi*; Iwamoto, Osamu; Iwamoto, Nobuyuki; Kawamura, Shiori*; Kimura, Atsushi; Kitaguchi, Masaaki*; Kobayashi, Ryuju*; et al.

European Physical Journal A, 60(8), p.166_1 - 166_10, 2024/08

https://doi.org/10.1140/epja/s10050-024-01392-6

Evaluation of bond repair effect for ultra-high-strength concrete specimens by neutron diffraction method

Yasue, Ayumu*; Kobayashi, Kensuke*; Yoshioka, Masahiro*; Noma, Takashi*; Okuno, Koichi*; Tanaka, Seiichiro*; Hirata, Yoshikazu*; Ooka, Tokunao*; Kimura, Yoshiharu*; Nagai, Tomoya*; et al.

Journal of Advanced Concrete Technology, 21(5), p.337 - 350, 2023/05

https://doi.org/10.3151/jact.21.337

The purpose of this study was to evaluate the use of resin injection to repair cracks in ultra-high-strength concrete (UHSC) members. As a preliminary step, the applicability of the neutron diffraction method (NDM) to investigate the effect of repairs in UHSC specimens was examined. The experimental results showed that the NDM can measure stresses in rebars in UHSC and normal concrete specimens. Therefore, in this experiment, the NDM was used to measure the bond performance of repairs with epoxy resin around the slit in normal concrete and UHSC specimens and examine the effect of repair on the UHSC specimens. Displacement around the slit was measured using a PI-shape displacement transducer. The evaluation confirmed that the bond performance of the repaired area was recovered by resin injection regardless of the concrete strength. In addition, the displacement around the slit was smaller for the injected specimens than the noninjected specimens. These experimental results clarified that by injecting resin, the same bond repair effect could be obtained in UHSC and normal concrete specimens.

Measurement of the transverse asymmetry of rays in the Sn()Sn reaction

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

https://doi.org/10.1103/PhysRevC.106.064601

no abstracts in English

Energy-dependent angular distribution of individual rays in the La()La reaction

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

https://doi.org/10.1103/PhysRevC.104.014601

Measurement of Angular distributions of -rays from La+n to excited states of La

Okudaira, Takuya; Endo, Shunsuke; Hirota, Katsuya*; Ishizaki, Kohei*; Kimura, Atsushi; Kitaguchi, Masaaki*; Koga, Jun*; Sakai, Kenji; Shimizu, Hirohiko*; Takada, Shusuke*; et al.

JPS Conference Proceedings (Internet), 33, p.011121_1 - 011121_3, 2021/03

https://doi.org/10.7566/JPSCP.33.011121

The technology development section develops the neutron polarization device: He Spin Filter, which can polarize neutrons in wide energy range. Polarized epi-thermal neutrons, which can be produced using He spin filter, can be useful for fundamental physics. Time-reversal violation beyond the Standard Model of elementary particles is one of the biggest problems to solve the mystery of the origin of the universe. An experiment with polarized epi-thermal neutrons and a polarized target to search for the T-violation using compound nuclei is planned at J-PARC. The measurement result of the angular distributions of -rays from La+n to excited states of La is presented.

Validation of repairing method for concrete wall of the JMTR tank-yard building

Sugaya, Naoto; Okada, Yuji; Nishimura, Arashi; Sonobe, Hiroshi; Kimura, Nobuaki; Kimura, Akihiro; Hanawa, Yoshio; Nemoto, Hiroyoshi

JAEA-Testing 2020-004, 67 Pages, 2020/08

JAEA-Testing-2020-004.pdf:8.17MB

In the Japan Materials Testing Reactor (JMTR), the leakage accidents of radioactive waste liquid were occurred from the tanks and pipes of the liquid waste disposal facility in the JMTR tank-yard building in JFY2014. In order to respond to the accident, the tanks and pipes were replaced from JFY2016 to 2019. On the other hand, a lot of cracks were occurred on the concreate wall of the tank-yard building when the frame structure supports were fixed to the concrete wall in the replacement work. Thus, it is necessary to repair the concreate wall of the tank-yard building. Especially, some cracks with swelling (cone-shaped fracture) were raised around some anchor bolts (the post-installed chemical anchor bolts) fixed the frame structure supports. The repairing method for the cone-shaped fracture of the concrete wall is standardized, but there was no reference value of tensile strength for the validation of the post-installed chemical anchor bolts after the repairing method. In this report, the repairing method was selected for the cone-shaped fracture on the concreate wall and the reference value of tensile strength for the validation of the post-installed chemical anchor bolts by this repairing method. The mock-ups for repairing cone-shaped fracture were fabricated by the selected repairing method and the tensile tests of the post-installed chemical anchor bolts were performed. From the results, the validation of the repairing method was obtained in this test and it was obvious the repairing of cone-shaped fracture is preferable method for the concreate wall of the JMTR tank-yard building.

Measurement of the angular distribution of -rays after neutron capture by La for a T-violation search

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

https://doi.org/10.1051/epjconf/201921909001

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 atmcm 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.

Characterization of germanium detectors for the measurement of the angular distribution of prompt -rays at the ANNRI in the MLF of the J-PARC

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

https://doi.org/10.1088/1748-0221/13/02/P02018

Development of prototype nuclear forensics library for radioactive isotopes at Japan Atomic Energy Agency

Kimura, Yoshiki; Shinohara, Nobuo; Funatake, Yoshio

57th Annual Meeting of the Institute of Nuclear Materials Management (INMM 2016), Vol.2, p.1024 - 1029, 2016/07