Refine your search:     
Report No.
 - 
Search Results: Records 1-20 displayed on this page of 447

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

Magnetic and fermi surface properties of semimetals EuAs$$_3$$ and Eu(As$$_{1-x}$$P$$_x$$)$$_3$$

Onuki, Yoshichika*; Karube, Kosuke*; Aoki, Dai*; Nakamura, Ai*; Homma, Yoshiya*; Matsuda, Tatsuma*; Haga, Yoshinori; Takeuchi, Tetsuya*

Journal of the Physical Society of Japan, 92(11), p.114703_1 - 114703_12, 2023/11

 Times Cited Count:0 Percentile:0(Physics, Multidisciplinary)

Journal Articles

Present status of JAEA-Tokai tandem accelerator

Kutsukake, Kenichi; Matsuda, Makoto; Nakamura, Masahiko; Ishizaki, Nobuhiro; Kabumoto, Hiroshi; Otokawa, Yoshinori; Asozu, Takuhiro; Matsui, Yutaka; Nakagawa, Sohei; Abe, Shinichi

Proceedings of 20th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1080 - 1084, 2023/11

no abstracts in English

JAEA Reports

Development of bearing units used in the rotating shaft system for power generation in the JAEA-Tokai Tandem accelerator

Otokawa, Yoshinori; Matsuda, Makoto; Abe, Shinichi

JAEA-Technology 2022-037, 23 Pages, 2023/03

JAEA-Technology-2022-037.pdf:5.38MB

Bearing units of rotating shaft system for power generation in the JAEA-Tokai Tandem accelerator had a short operating life from the beginning of the accelerator installation, and even after replacing the bearing unit, early failures often occurred. Therefore, the quantity and frequency of replacement are large, and a lot of time is spent in regular maintenance performed by opening the accelerator pressure vessel, and solving this problem has been a long-standing concern. As a result of considering the cause of this early failure, it was considered that the load caused by parallel, angular, and axial misalignment of the upper and lower bearing units was the cause. In order to solve this problem, we have developed a bearing unit having metal disc-spring couplings in the upper and lower flanges to allow for parallel, angular, and axial misalignment of bearing units. As a result, it is now possible to allow variations in the distance between castings and parallel, angular, and axial misalignment of the upper and lower bearing units. By installing the developed new bearing unit on the rotating shaft system and making improvements while continuing to use it in actual operation, we succeeded in reducing the early failure and extending the operating life by more than double. With this development, the maintenance time has been reduced to one week by reducing the number of replacing the bearing unit. In addition, we have realized one regular maintenance that was carried out about three times a year, and as a benefit, we were able to reduce the amount of sulfur hexafluoride (SF$$_{6}$$) gas, which is a greenhouse gas, to about 33$$sim$$50% per year. We describe about development of new bearing units and these maintenance status from 2006 to 2020.

Journal Articles

Present status of JAEA-Tokai tandem accelerator

Kabumoto, Hiroshi; Matsuda, Makoto; Nakamura, Masahiko; Ishizaki, Nobuhiro; Kutsukake, Kenichi; Otokawa, Yoshinori; Asozu, Takuhiro; Matsui, Yutaka; Nakagawa, Sohei; Abe, Shinichi

Proceedings of 19th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1109 - 1113, 2023/01

no abstracts in English

Journal Articles

Single crystal growth and magnetic properties of $$alpha$$-Mn and $$beta$$-Mn

Onuki, Yoshichika*; Aoki, Dai*; Nakamura, Ai*; Matsuda, Tatsuma*; Nakashima, Miho*; Haga, Yoshinori; Takeuchi, Tetsuya*

Journal of the Physical Society of Japan, 91(6), p.065001_1 - 065001_2, 2022/06

 Times Cited Count:0 Percentile:0(Physics, Multidisciplinary)

Journal Articles

Single crystal growth and magnetic properties of noncentrosymmetric antiferromagnet Mn$$_3$$IrSi

Onuki, Yoshichika*; Kaneko, Yoshio*; Aoki, Dai*; Nakamura, Ai*; Matsuda, Tatsuma*; Nakashima, Miho*; Haga, Yoshinori; Takeuchi, Tetsuya*

Journal of the Physical Society of Japan, 91(6), p.065002_1 - 065002_2, 2022/06

 Times Cited Count:2 Percentile:28(Physics, Multidisciplinary)

Journal Articles

Split Fermi surface properties of noncentrosymmetric compounds Fe$$_2$$P, Ni$$_2$$P, and Pd$$_2$$Si

Onuki, Yoshichika*; Nakamura, Ai*; Aoki, Dai*; Matsuda, Tatsuma*; Haga, Yoshinori; Harima, Hisatomo*; Takeuchi, Tetsuya*; Kaneko, Yoshio*

Journal of the Physical Society of Japan, 91(6), p.064712_1 - 064712_10, 2022/06

 Times Cited Count:1 Percentile:28(Physics, Multidisciplinary)

Journal Articles

Present status of JAEA-Tokai tandem accelerator

Matsuda, Makoto; Tayama, Hidekazu; Ishizaki, Nobuhiro; Kabumoto, Hiroshi; Nakamura, Masahiko; Kutsukake, Kenichi; Otokawa, Yoshinori; Asozu, Takuhiro; Matsui, Yutaka; Abe, Shinichi

Proceedings of 18th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.394 - 398, 2021/10

no abstracts in English

Journal Articles

Rabi-oscillation spectroscopy of the hyperfine structure of muonium atoms

Nishimura, Shoichiro*; Torii, Hiroyuki*; Fukao, Yoshinori*; Ito, Takashi; Iwasaki, Masahiko*; Kanda, Sotaro*; Kawagoe, Kiyotomo*; Kawall, D.*; Kawamura, Naritoshi*; Kurosawa, Noriyuki*; et al.

Physical Review A, 104(2), p.L020801_1 - L020801_6, 2021/08

 Times Cited Count:13 Percentile:83.13(Optics)

Journal Articles

Present status of JAEA-Tokai tandem accelerator

Matsuda, Makoto; Ishizaki, Nobuhiro; Tayama, Hidekazu; Kabumoto, Hiroshi; Nakamura, Masahiko; Kutsukake, Kenichi; Otokawa, Yoshinori; Asozu, Takuhiro; Matsui, Yutaka; Abe, Shinichi; et al.

Proceedings of 17th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.948 - 952, 2020/09

no abstracts in English

Journal Articles

Quasi-one-dimensional magnetic interactions and conduction electrons in EuCu$$_5$$ and EuAu$$_5$$ with the characteristic hexagonal structure

Matsuda, Shinya*; Ota, Joji*; Nakaima, Kenri*; Iha, Wataru*; Gochi, Jun*; Uwatoko, Yoshiya*; Nakashima, Miho*; Amako, Yasushi*; Honda, Fuminori*; Aoki, Dai*; et al.

Philosophical Magazine, 100(10), p.1244 - 1257, 2020/04

 Times Cited Count:3 Percentile:19.68(Materials Science, Multidisciplinary)

Journal Articles

The $$f$$-electron state of the heavy fermion superconductor NpPd$$_5$$Al$$_2$$ and the isostructural family

Metoki, Naoto; Aczel, A. A.*; Aoki, Dai*; Chi, S.*; Fernandez-Baca, J. A.*; Griveau, J.-C.*; Hagihara, Masato*; Hong, T.*; Haga, Yoshinori; Ikeuchi, Kazuhiko*; et al.

JPS Conference Proceedings (Internet), 30, p.011123_1 - 011123_6, 2020/03

Rare earths (4$$f$$) and actinides (5$$f$$) provide variety of interesting states realized with competing interactions between the increasing number of $$f$$ electrons. Since crystal field splitting of many-body $$f$$ electron system is smaller than the bandwidth, (1) high resolution experiments are needed, (2) essentially no clear spectrum with well defined peaks is expected in itinerant Ce and U compounds, and (3) Np and Pu is strictly regulated. Therefore, systematic research on magnetic excitations by neutron scattering experiments of localized compounds and rare earth iso-structural reference is useful. We describe the $$f$$ electron states of heavy electron compounds NpPd$$_5$$Al$$_2$$ and actinide and rare earth based iso-structural family.

Journal Articles

Symmetry of hidden ordered state in URu$$_2$$Si$$_2$$; Our current understanding

Kambe, Shinsaku; Tokunaga, Yo; Sakai, Hironori; Matsuda, Tatsuma*; Haga, Yoshinori; Walstedt, R. E.*; Harima, Hisatomo*

JPS Conference Proceedings (Internet), 30, p.011035_1 - 011035_5, 2020/03

Owing to recent investigations, understanding of the symmetry of hidden order and superconductivity in URu$$_2$$Si$$_2$$ is fairly progressed. It seems that we are not far from the answer. Following issues and perspectives will be discussed.

Journal Articles

Present status of JAEA-Tokai tandem accelerator

Matsuda, Makoto; Osa, Akihiko; Ishizaki, Nobuhiro; Tayama, Hidekazu; Kabumoto, Hiroshi; Nakamura, Masahiko; Kutsukake, Kenichi; Otokawa, Yoshinori; Asozu, Takuhiro; Matsui, Yutaka; et al.

Proceedings of 16th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1270 - 1273, 2019/07

The JAEA-Tokai tandem accelerator was operated over a total of 138 days, and delivered 16 different ions to the experiments in the research fields of nuclear physics, nuclear chemistry, atomic physics, solid state physics and radiation effects in material in FY2018. Maximum acceleration voltage was 16.6 MV. A new beam attenuator was installed at the entrance beam line of the tandem accelerator to facilitate control of the beam current and minimize stripper foil consumption. The main maintenance items included replacing the pellet chain used for about 68,000 hours and the drive motor for the high voltage terminal generator used for about 9 years. A fault has occurred in the building's oxygen deficiency monitor. This paper describes the operational status of the accelerators and the major technical developments of our facility.

Journal Articles

Anomalous ferromagnetic ordering in EuCuP

Iha, Wataru*; Kakihana, Masashi*; Matsuda, Shinya*; Honda, Fuminori*; Haga, Yoshinori; Takeuchi, Tetsuya*; Nakashima, Miho*; Amako, Yasushi*; Gochi, Jun*; Uwatoko, Yoshiya*; et al.

Journal of Alloys and Compounds, 788, p.361 - 366, 2019/06

 Times Cited Count:6 Percentile:33.98(Chemistry, Physical)

Journal Articles

The Present conditions of the acceleration voltage after the acceleration tube update

Matsuda, Makoto; Osa, Akihiko; Ishizaki, Nobuhiro; Tayama, Hidekazu; Nakanoya, Takamitsu; Kabumoto, Hiroshi; Nakamura, Masahiko; Kutsukake, Kenichi; Otokawa, Yoshinori; Asozu, Takuhiro

JAEA-Conf 2018-003, p.126 - 131, 2019/02

no abstracts in English

Journal Articles

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

Strasser, P.*; Abe, Mitsushi*; Aoki, Masaharu*; Choi, S.*; Fukao, Yoshinori*; Higashi, Yoshitaka*; Higuchi, Takashi*; Iinuma, Hiromi*; Ikedo, Yutaka*; Ishida, Katsuhiko*; et al.

EPJ Web of Conferences, 198, p.00003_1 - 00003_8, 2019/01

 Times Cited Count:13 Percentile:99.06(Quantum Science & Technology)

Journal Articles

Unique helical magnetic order and field-induced phase in trillium lattice antiferromagnet EuPtSi

Kaneko, Koji; Frontzek, M. D.*; Matsuda, Masaaki*; Nakao, Akiko*; Munakata, Koji*; Ohara, Takashi; Kakihana, Masashi*; Haga, Yoshinori; Hedo, Masato*; Nakama, Takao*; et al.

Journal of the Physical Society of Japan, 88, p.013702_1 - 013702_5, 2019/01

 Times Cited Count:60 Percentile:95.02(Physics, Multidisciplinary)

Journal Articles

Localized 5$$f^2$$ states in UPd$$_5$$Al$$_2$$ and valence crossover in the Vicinity of Heavy-Fermion superconductivity

Metoki, Naoto; Haga, Yoshinori; Yamamoto, Etsuji; Matsuda, Masaaki*

Journal of the Physical Society of Japan, 87(11), p.114712_1 - 114712_9, 2018/11

 Times Cited Count:3 Percentile:29.25(Physics, Multidisciplinary)

The localized 5$$f$$ states with 5$$f^2$$ ($$^3H_4$$) configuration of U$$^{4+}$$ ion have been revealed in UPd$$_5$$Al$$_2$$. We found that the low-lying states are the same as PrPd$$_5$$Al$$_2$$ flat orbitals with large $$J_z$$ are stabilized by a two-dimensional CEF potential in the unique crystal structure. The present study involves the valence crossover from tetravalent to trivalent in a series of AnPd$$_5$$Al$$_2$$, demonstrated by lattice and/or transport anomaly as well as many body effects in the vicinity of the boundary. The valence instability plays important role for the unusual heavy fermion superconductivity in NpPd$$_5$$Al$$_2$$.

Journal Articles

Phenomenological approach to study the degree of the itinerancy of the 5$$f$$ electrons in actinide ferromagnets with spin fluctuation theory

Tateiwa, Naoyuki; Posp$'i$$v{s}$il, J.*; Haga, Yoshinori; Sakai, Hironori; Matsuda, Tatsuma*; Yamamoto, Etsuji

Progress in Nuclear Science and Technology (Internet), 5, p.104 - 107, 2018/11

Uranium ferromagnetic superconductors UGe$$_2$$, URhGe and UCoGe have attracted much attention from both theoretical and experimental sides since the same 5$$f$$ electrons underlie carry both the ferromagnetism and superconductivity. Recently, we have analysed 69 uranium, 7 neptunium, and 4 plutonium ferromagnets with spin fluctuation theory originally developed for researches on itinerant ferromagnets in the 3$$d$$ transition metals and their intermetallics. The applicability of the spin fluctuation theory to the actinide 5$$f$$ system has been confirmed and the itinerant character of the 5f electrons is suggested in the actinide ferromagnets. In this conference, two results will be shown. One is the results of the analyses on 80 actinide ferromagnets and the other is the pressure dependence of the spin fluctuation parameters in UGe$$_2$$.

447 (Records 1-20 displayed on this page)