研究者詳細 - 北口　雅暁

論文 - 北口　雅暁

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Generation of 4He2* Clusters via Neutron-3He Absorption Reaction Toward Visualization of Full Velocity Field in Quantum Turbulence 査読有り国際誌

Matsushita, T; Sonnenschein, V; Guo, W; Hayashida, H; Hiroi, K; Hirota, K; Iguchi, T; Ito, D; Kitaguchi, M; Kiyanagi, Y; Kokuryu, S; Kubo, W; Saito, Y; Shimizu, HM; Shinohara, T; Suzuki, S; Tomita, H; Tsuji, Y; Wada, N

JOURNAL OF LOW TEMPERATURE PHYSICS 196 巻 ( 1-2 ) 頁： 275 - 282 2019年7月

First ultracold neutrons produced at TRIUMF 査読有り国際共著国際誌

Ahmed, S; Altiere, E; Andalib, T; Bell, B; Bidinosti, CP; Cudmore, E; Das, M; Davis, CA; Franke, B; Gericke, M; Giampa, P; Gnyp, P; Hansen-Romu, S; Hatanaka, K; Hayamizu, T; Jamieson, B; Jones, D; Kawasaki, S; Kikawa, T; Kitaguchi, M; Klassen, W; Konaka, A; Korkmaz, E; Kuchler, F; Lang, M; Lee, L; Lindner, T; Madison, KW; Makida, Y; Mammei, J; Mammei, R; Martin, JW; Matsumiya, R; Miller, E; Mishima, K; Momose, T; Okamura, T; Page, S; Picker, R; Pierre, E; Ramsay, WD; Rebenitsch, L; Rehm, F; Schreyer, W; Shimizu, HM; Sidhu, S; Sikora, A; Smith, J; Tanihata, I; Thorsteinson, B; Vanbergen, S; van Oers, WTH; Watanabe, YX

PHYSICAL REVIEW C 99 巻 ( 2 ) 2019年2月

記述言語：英語掲載種別：研究論文（学術雑誌）

© 2019 American Physical Society. We installed a source for ultracold neutrons at a new, dedicated spallation target at TRIUMF. The source was originally developed in Japan and uses a superfluid-helium converter cooled to 0.9K. During an extensive test campaign in November 2017, we extracted up to 325000 ultracold neutrons after a one-minute irradiation of the target, over three times more than previously achieved with this source. The corresponding ultracold-neutron density in the whole production and guide volume is 5.3cm-3. The storage lifetime of ultracold neutrons in the source was initially 37 s and dropped to 24 s during the 18 days of operation. During continuous irradiation of the spallation target, we were able to detect a sustained ultracold-neutron rate of up to 1500s-1. Simulations of UCN production, UCN transport, temperature-dependent UCN yield, and temperature-dependent storage lifetime show excellent agreement with the experimental data and confirm that the ultracold-neutron-upscattering rate in superfluid helium is proportional to T7.

DOI： 10.1103/PhysRevC.99.025503

Web of Science

Scopus

Pendellosung interferometry by using pulsed neutrons (vol 908, pg 78, 2018)

Itoh, S; Nakaji, M; Uchida, Y; Kitaguchi, M; Shimizu, HM

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 918 巻頁： 99 - 99 2019年2月

New precise measurements of muonium hyperfine structure at J-PARC MUSE

Strasser P., Abe M., Aoki M., Choi S., Fukao Y., Higashi Y., Higuchi T., Iinuma H., Ikedo Y., Ishida K., Ito T., Ito T. U., Iwasaki M., Kadono R., Kamigaito O., Kanda S., Kawagoe K., Kawall D., Kawamura N., Kitaguchi M., Koda A., Kojima K. M., Kubo K., Matama M., Matsuda Y., Matsudate Y., Mibe T., Miyake Y., Mizutani T., Nagamine K., Nishimura S., Ogitsu T., Saito N., Sasaki K., Seo S., Shimizu H. M., Shimomura K., Suchara T., Tajima M., Tanaka K. S., Tanaka T., Tojo J., Tomono D., Torii H. A., Torikai E., Toyoda A., Tsutsumi Y., Ueno K., Ueno Y., Yagi D., Yamamoto A., Yamanaka T., Yamazaki T., Yasuda H., Yoshida M., Yoshioka T.

QUANTUM TECHNOLOGY INTERNATIONAL CONFERENCE 2018 (QTECH 2018) 198 巻 2019年

時間反転対称性の破れ探索のための複合核反応を用いた113Cdの7.0 eV p波由来のγ線測定

牧瀬壮, 高田秀佐, 古賀淳, 吉岡瑞樹, 清水裕彦, 山本知樹, 石崎貢平, 遠藤駿典, 佐藤匠, 新實裕大, 北口雅暁, 広田克也, 嶋達志, 吉川大幹, 藤岡宏之, 谷結以花, 奥平琢也, 木村敦, 酒井健二, 他NOPTREXコラボレーション

日本物理学会講演概要集 74.1 巻頁： 273 - 273 2019年

A search for deviations from the inverse square law of gravity at nm range using a pulsed neutron beam 査読有り国際共著国際誌

Christopher Haddock, Katsuya Hirota, Takashi Ino, Masaaki Kitaguchi, Kenji Mishima, Noriko Oi, Tatsushi Shima, Hirohiko Shimizu, W. Michael Snow, Tamaki Yoshioka

EPJ Web of Conferences 219 巻頁： 05002 - 05002 2019年

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）出版者・発行元：EDP Sciences

Recently published results and ongoing experimental efforts to search for deviations from the inverse square law of gravity at the nanometer length scale using slow neutron scattering from the noble gases are discussed. Using the pulsed slow neutron beamline BL05 at the Materials and Life Sciences Facility at J-PARC, we measured the neutron momentum transfer (q) dependence of the differential scattering cross section for the noble gases He, Ne, Ar, Kr, and Xe. By comparing to the distributions obtained using pseudo-experimental Monte Carlo simulations and forming ratios between Xe and He, we placed an upper bound on the strength of a new interaction as a function of interaction length λ which improved upon previous results in the region λ < 0.1 nm, and remains competitive in the larger λ region. Additionally we describe how we are using our technique to extract relative values of the total neutron scattering cross sections of the noble gases, as well as how we plan to measure the neutron-electron scattering length using the NOVA instrument on BL21 at J-PARC.

DOI： 10.1051/epjconf/201921905002

Development of the neutron polarizer for the T-violation search using compound nuclei 査読有り国際誌

T. Okudaira, T. Oku, K. Sakai, T. Ino, H. Hayashida, K. Hiroi, T. Shinohara, K. Kakurai, K. Aizawa, H. M. Shimizu, M. Kitaguchi, T. Yamamoto

Proceedings of Science 356 巻 2019年

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

© Copyright owned by the author(s). The fundamental parity violation is enhanced by 106 times at maximum in several neutron induced compound nuclei. There is a theoretical prediction that fundamental T-violating effects can be also largely enhanced in compound nuclei implying that T-violation can be searched for by making very sensitive measurements. A T-violation search experiment using compound nuclei is planned at J-PARC. Polarized epithermal neutron beam, polarized nuclear target, and high count rate neutron detector are necessary for the experiment, and therefore a development of the neutron polarizer using polarized 3He is ongoing at J-PARC in JAEA. Recently, a clean vacuum system to fabricate 3He spin filters was constructed, and several 3He spin filters were fabricated. The current status of the development of the 3He spin filter was reported.

Scopus

Measurement of P-Violation in 139La(n,γ)140La – a first step towards a T-Violation search 査読有り

Tomoki Yamamoto, Hirohiko M. Shimizu, Masaaki Kitaguchi, Katsuya Hirota, Christopher C. Haddock, Shunsuke Endo, Kohei Ishizaki, Takumi Sato, Shusuke Takada, Jun Koga, Tamaki Yoshioka, Takashi Ino, Koichiro Asahi, Takamasa Momose, Takahiro Iwata, Kenji Sakai, Takuya Okudaira, Takayuki Oku, Atsushi Kimura, Masahiro Hino, Tatsushi Shima, Yutaka Yamagata

EPJ Web of Conferences 219 巻頁： 09002 - 09002 2019年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：{EDP} Sciences

<jats:p>We performed a polarized neutron transmission asymmetry measurement utilizing the <jats:sup>139</jats:sup>La(<jats:italic>n</jats:italic>,γ)<jats:sup>140</jats:sup>La reaction. This measurement involved the use of a recently developed <jats:sup>3</jats:sup>He spin filter mounted on the J-PARC MLF beam line number 4 (BL04). The resulting value of the longitudinal asymmetry <jats:italic>A</jats:italic><jats:sub><jats:italic>L</jats:italic></jats:sub> = (11.7 ± 1.1)% was found to be in good agreement with existing values in the literature suggesting that the method by which we polarize the neutron beam is not a significant source of uncertainty. This preliminary work represents a first step toward future measurements of the angular correlation in (<jats:italic>n̅</jats:italic>,<jats:italic>Υ</jats:italic>) reactions necessary in the search for enhanced T-Violation in compound nuclei.</jats:p>

DOI： 10.1051/epjconf/201921909002

Verification of the compound nuclear model for T-violation search

T. Yamamoto, H. M. Shimizu, K. Ishizaki, Y. Niinomi, M. Kitaguchi, S. Takada, J. Koga, S. Makise, T. Yoshioka, A. Kimura, K. Sakai, T. Oku, T. Okudaira, S. Endo, Y. Tani, H. Fujioka, H. Yoshikawa, K. Hirota, T. Shima

Proceedings of Science 356 巻 2019年

掲載種別：研究論文（国際会議プロシーディングス）

Large sources of parity violation have been observed in compound nuclear reactions. These enhancements are described by the compound nuclear model, which can be used to describe the angular correlation of γ-rays produced in (n; γ) reactions in medium-heavy nuclei. It has also been suggested that these same reactions could lead to a similar enhancement in time reversal violating processes. Therefore, we are interested in verifying the compound nuclear model by studying the (n; γ) reaction using polarized neutrons. In this paper, we discuss the installation and characterization of a neutron polarizer used in the (n; γ) measurement with transversely polarized neutrons.

DOI： 10.22323/1.356.0042

Scopus

New project for precise neutron lifetime measurement at J-PARC

Naoki Nagakura, Katsuya Hirota, Sei Ieki, Takashi Ino, Yoshihisa Iwashita, Masaaki Kitaguchi, Ryunosuke Kitahara, Jun Koga, Kenji Mishima, Aya Morishita, Yusuke Nakano, Hideyuki Oide, Hiroki Okabe, Hidetoshi Otono, Yoshichika Seki, Daiichiro Sekiba, Tatsushi Shima, Hirohiko Shimizu, Naoyuki Sumi, Hirochika Sumino, Kaoru Taketani, Tatsuhiko Tomita, Hideaki Uehara, Takahito Yamada, Satoru Yamashita, Mami Yokohashi, Tamaki Yoshioka

EPJ Web of Conferences 219 巻頁： 03003 - 03003 2019年

掲載種別：研究論文（学術雑誌）出版者・発行元：EDP Sciences

The decay lifetime of free neutrons (∼880 s) is an important parameter of the weak interaction and for Big Bang Nucleosynthesis. However, results of measurements currently show discrepancies depending on the method used. As most experiments nowadays employ ultra cold neutrons, we have developed a new cold-beam experiment which we perform at the Japan Proton Accelerator Research Complex. As a special feature, a polarized neutron beam is bunched by a spin flip chopper. A time projection chamber operated with He and CO2 gas, including a well-controlled amount of 3He, is used for detection of the beta-decays and simultaneous determination of the beam intensity. Using the data between 2014 and 2016, we evaluated our first, preliminary result of the neutron lifetime as 896 ± 10(stat.) −10+14(sys.) s. We plan several upgrades to achieve our precision goal of 1 s.

DOI： 10.1051/epjconf/201921903003

Measurement of the angular distribution of prompt gamma-rays emitted in the 117Sn(n, γ) reaction for a T-violation search 査読有り

Jun Koga, Shusuke Takada, Tamaki Yoshioka, Hirohiko M. Shimizu, Katsuya Hirota, Norio Oi, Tomoki Yamamoto, Ikuya Ito, Kohei Ishizaki, Shunsuke Endo, Takumi Sato, Masaaki Kitaguchi, Christopher C. Haddock, Takuya Okudaira, Kenji Sakai, Atsushi Kimura

EPJ Web of Conferences 219 巻頁： 09004 - 09004 2019年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：{EDP} Sciences

<jats:p>It is theoretically suggested that the violation of charge conjugation and parity symmetry (CP-violation) could be enhanced in several compound nuclear reactions. According to the CPT theorem the violation of time-reversal symmetry (T-violation) would be enhanced too. The experimental sensitivity to find a T-violating effect in neutron-induced compound nuclear reactions depends on the value of a spin factor κ(<jats:italic>J</jats:italic>), which is a parameter specific for each nuclide. It can be determined from the angular dependence of γ-ray emission in (n,γ) reactions induced near a p-wave resonance. In this paper, the measurement result and the analysis status of experiments using the target nucleus <jats:sup>117</jats:sup>Sn are reported.</jats:p>

DOI： 10.1051/epjconf/201921909004

Measurement of the angular distribution of γ-rays emitted from the compound state after neutron capture by 81Br for a search of T-violation 査読有り国際共著国際誌

Shunsuke Endo, Hirohiko M. Shimizu, Masaaki Kitaguchi, Hirota Katsuya, Tomoki Yamamoto, Kohei Ishizaki, Takumi Sato, Tamaki Yoshioka, Shusuke Takada, Jun Koga, Takuya Okudaira, Kenji Sakai, Atsushi Kimura, Christopher C. Haddock

EPJ Web of Conferences 219 巻頁： 09003 - 09003 2019年

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）出版者・発行元：{EDP} Sciences

<jats:p>It is known that parity violation can be enhanced in compound nuclei due to mixing of s- and p-waves, and it is suggested that time reversal invariance (T) violation is enhanced by the same mechanism. We are planing a T-violation search using compound nuclei produced in neutron capture reactions. Although <jats:sup>81</jats:sup>Br is one of the candidate target nuclei, its sensitivity to T-violation has not yet been determined. For an estimate of the latter, a measurement of the angular distribution of γ-rays emitted in the <jats:sup>81</jats:sup>Br(n,γ) reaction was carried out in November 2017, of which we report first results.</jats:p>

DOI： 10.1051/epjconf/201921909003

Polarized lanthanum target for the t-violation search in slow neutron transmission 査読有り国際誌

Kohei Ishizaki, Hirohiko M. Shimizu, Masaaki Kitaguchi, Taku Matsushita, Masataka Iinuma, Hideki Kohri, Hiromoto Yoshikawa, Masaru Yosoi, Tatsushi Shima, Takahiro Iwata, Yoshiyuki Miyachi, Shigeru Ishimoto, Masaki Fujita, Yoichi Ikeda

Proceedings of Science 379 巻 2019年

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）出版者・発行元：Sissa Medialab Srl

The Nd3+ doped LaAlO3 crystal is a good candidate of a polarized 139La target for the search of the P-odd and T-odd interaction in the low-energy neutron absorption of 139La. As the first step for realizing the polarized 139La target, we grow the undoped LaAlO3 crystal and the La1−xNdxAlO3 (x = 5 ×10−4) crystal by floating-zone method with four halogen lamps. The ESR measurements of Nd3+ in the latter crystal indicated that the linewidth was about 6 gauss, whose value is the same as the crystal in which 50 % 139La polarization was achieved in the previous DNP experiment. As the result, the crystals grown by this method can be applicable to the target study for the T-violation search.

Scopus

Development of New Neutron Mirrors for Measuring the Neutron Electric Dipole Moment 査読有り国際誌

Ryo Katayama, Kenji Mishima, Satoru Yamashita, Masaaki Kitaguchi, Tamaki Yoshioka, Yoshichika Seki, Masahiko Mitsuhashi, Masahiko Sugihara, Masahiro Hino, Eiichiro Watanabe, Daiju Tsuya, Mikiko Saito, Norifumi L. Yamada

Proceedings of the International Conference on Neutron Optics (NOP2017) 2018年11月

A cold/ultracold neutron detector using fine-grained nuclear emulsion with spatial resolution less than 100 nm 査読有り国際誌

Naganawa, N; Ariga, T; Awano, S; Hino, M; Hirota, K; Kawahara, H; Kitaguchi, M; Mishima, K; Shimizu, HM; Tada, S; Tasaki, S; Umemoto, A

EUROPEAN PHYSICAL JOURNAL C 78 巻 ( 11 ) 2018年11月

Pendellosung interferometry by using pulsed neutrons 査読有り

Itoh, S; Nakaji, M; Uchida, Y; Kitaguchi, M; Shimizu, HM

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 908 巻頁： 78 - 81 2018年11月

A Search for Possible Deviations from Newtonian Gravity at the nm Length Scale Using Neutron-Noble Gas Scattering 査読有り国際共著国際誌

Noriko Oi, Hirohiko M. Shimizu, Katsuya Hirota, Masaaki Kitaguchi, Christopher C. Haddock, William M. Snow, Tamaki Yoshioka, Kenji Mishima, Takashi Ino, Tatsushi Shima

JPS Conference Proceedings 2018年11月

Measurement of Angular Distributions in 139La(n,γ) Reaction for T violation Search 査読有り

T. Okudaira, H, M. Shimizu, M. Kitaguchi, K. Hirota, C. C. Haddock, N. Oi, I. Ito, T. Yamamoto, S. Endo, S. Takada, J. Koga, T. Yoshioka, T. Ino, K. Asahi, T. Momose, T. Iwata, K. Sakai, T. Oku, A. Kimura, M. Hino, T. Shima, Y. Yamagata

JPS Conference Proceedings 2018年11月

Measurement of Angular Distributions in 139La(n,gamma) Reaction for T Violation Search 査読有り

T. Okudaira, H.M. Shimizu, M. Kitaguchi, K. Hirota, C.C. Haddock, N. Oi, I. Ito, T. Yamamoto, S. Endo, S. Takada, J. Koga, T. Yoshioka, T. Ino, K. Asahi, T. Momose, T. Iwata, K. Sakai, T. Oku, A. Kimura, M. Hino, T. Shima, Y. Yamagata

JPS Conference Proceedings 2018年11月

Measurement of (n,gamma) Reaction of 117Sn for T-Violation Search by Using Compound Nucleus 査読有り

J. Koga, S. Takada, T. Yoshioka, H.M. Shimizu, K. Hirota, T. Okudaira, N. Oi, I. Ito, T. Yamamoto, S. Endo, C.C. Haddock, M. Kitaguchi, A. Kimura, K. Sakai, T. Ino, K. Asahi, T. Momose, T. Iwata, M. Hino, T. Shima, Y. Yamagata

JPS Conference Proceedings 2018年11月

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