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Higemoto, Wataru; Yokoyama, Makoto*; Ito, Takashi; Suzuki, Taiga*; Raymond, S.*; Yanase, Yoichi*
Proceedings of the National Academy of Sciences of the United States of America, 119(49), p.e2209549119_1 - e2209549119_6, 2022/11
Times Cited Count:0 Percentile:0(Multidisciplinary Sciences)no abstracts in English
Ito, Takashi
Meson, (56), p.21 - 26, 2022/09
no abstracts in English
Nakamura, Jumpei*; Kawakita, Yukinobu; Shimomura, Koichiro*; Suemasu, Takashi*
Journal of Applied Physics, 130(19), p.195701_1 - 195701_7, 2021/11
Times Cited Count:2 Percentile:7.86(Physics, Applied)Fittipaldi, R.*; Hartmann, R.*; Mercaldo, M. T.*; Komori, Sachio*; Bjrlig, A.*; Higemoto, Wataru; Maeno, Yoshiteru*; Di Bernardo, A.*; 18 of others*
Nature Communications (Internet), 12, p.5792_1 - 5792_9, 2021/10
Times Cited Count:11 Percentile:64.44(Multidisciplinary Sciences)The layered oxide perovskite SrRuO, which has been intensively investigated due to its unusual properties. Whilst the debate on the symmetry of the superconducting state in SrRuO is still ongoing, a deeper understanding of the SrRuO normal state appears crucial as this is the background in which electron pairing occurs. Here, by using low-energy muon spin spectroscopy we discover the existence of surface magnetism in SrRuO at an onset temperature higher than 50 K. Our observations set a reference for the discovery of the same magnetic phase in other materials.
Okuma, Ryutaro*; Kofu, Maiko; Asai, Shinichiro*; Avdeev, M.*; Koda, Akihiro*; Okabe, Hirotaka*; Hiraishi, Masatoshi*; Takeshita, Soshi*; Kojima, Kenji*; Kadono, Ryosuke*; et al.
Nature Communications (Internet), 12, p.4382_1 - 4382_7, 2021/07
Times Cited Count:7 Percentile:61.42(Multidisciplinary Sciences)Suzuki, Shintaro*; Takubo, Ko*; Kuga, Kentaro*; Higemoto, Wataru; Ito, Takashi; Tomita, Takahiro*; Shimura, Yasumichi*; Matsumoto, Yosuke*; Bareille, C.*; Wadachi, Hiroki*; et al.
Physical Review Research (Internet), 3(2), p.023140_1 - 023140_12, 2021/05
We report our experimental discovery of the transition temperature reaching 20 K in a Yb-based compound at ambient pressure. The Mn substitution at the Al site in an intermediate valence state of -YbAlB not only induces antiferromagnetic transition at a record high temperature of 20 K but also transforms the heavy-fermion liquid state in -YbAlB into a highly resistive metallic state proximate to a Kondo insulator.
Sugiyama, Jun; Higemoto, Wataru; Andreica, D.*; Forslund, O. K.*; Nocerino, E.*; Mnsson, M.*; Sassa, Y.*; Gupta, R.*; Khasanov, R.*; Ota, Hiroto*; et al.
Physical Review B, 103(10), p.104418_1 - 104418_10, 2021/03
Times Cited Count:8 Percentile:57.35(Materials Science, Multidisciplinary)The magnetic nature of a quasi-one-dimensional compound, BaVSe, has been investigated with positive muon spin rotation and relaxation measurements at ambient and high pressures. At ambient pressure, the spectrum recorded under zero external magnetic field exhibited a clear oscillation below the Curie temperature due to the formation of quasistatic ferromagnetic order. As pressure increased from ambient pressure, was found to decrease slightly up to about 1.5 GPa, at which point started to increase rapidly with the further increase of the pressure. Based on a strong ferromagnetic interaction along the -axis, the result revealed that there are two magnetic interactions in the ab-plane.
Yamauchi, Hiroki; Sari, D. P.*; Watanabe, Isao*; Yasui, Yukio*; Chang, L.-J.*; Kondo, Keietsu; Ito, Takashi; Ishikado, Motoyuki*; Hagihara, Masato*; Frontzek, M. D.*; et al.
Communications Materials (Internet), 1, p.43_1 - 43_6, 2020/07
High-temperature short-range order is discovered up to 720 K in MnRhSi by complementary use of neutron scattering and muon spin relaxation measurements.
Fujihara, Masayoshi*; Morita, Katsuhiro*; Mole, R.*; Mitsuda, Setsuo*; Toyama, Takami*; Yano, Shinichiro*; Yu, D.*; Sota, Shigetoshi*; Kuwai, Tomohiko*; Koda, Akihiro*; et al.
Nature Communications (Internet), 11, p.3429_1 - 3429_7, 2020/07
Times Cited Count:39 Percentile:90.63(Multidisciplinary Sciences)Pant, A. D.*; Higemoto, Wataru; Miyake, Yasuhiro; 8 of others*
Nuclear Instruments and Methods in Physics Research A, 929, p.129 - 133, 2019/06
Times Cited Count:5 Percentile:48.99(Instruments & Instrumentation)We have been developing an ultra slow muon microscope, at J-PARC. We performed Monte Carlo simulations, the results of which pointed out the significant effect of a stray magnetic field at the muonium chamber on the beam profile at sample position. To minimize this effect, we steered the beam using imbalance tuning of electric quadrupoles. This paper presents the simulation study of beam transportation, optimization, and characterization in terms of beam size, time, and energy distribution at sample position in one of the experimental areas, namely, U1A.
Yoshida, Go*; Ninomiya, Kazuhiko*; Inagaki, Makoto*; Higemoto, Wataru; Strasser, P.*; Kawamura, Naritoshi*; Shimomura, Koichiro*; Miyake, Yasuhiro*; Miura, Taichi*; Kubo, Kenya*; et al.
Journal of Radioanalytical and Nuclear Chemistry, 320, p.283 - 289, 2019/05
Times Cited Count:4 Percentile:41.24(Chemistry, Analytical)The role of valence electrons for the muon capture process by molecules is experimentally investigated with the aid of cascade calculations. Low-momentum muons are introduced to gas targets below atmospheric pressure. The initial states of captured muons are determined from the measured muonic X-ray structure of the Lyman and Balmer series. We propose that the lone pair electrons in the carbon atom of CO significantly contribute to the capture of a muon with large angular momenta.
Sugiyama, Jun*; Umegaki, Izumi*; Nozaki, Hiroshi*; Higemoto, Wataru; Hamada, Koji*; Takeshita, Soshi*; Koda, Akihiro*; Shimomura, Koichiro*; Ninomiya, Kazuhiko*; Kubo, Kenya*
Physical Review Letters, 121(8), p.087202_1 - 087202_5, 2018/08
Times Cited Count:18 Percentile:74.47(Physics, Multidisciplinary)Kawamura, Seiko; Tomiyasu, Keisuke*; Koda, Akihiro*; Sari, D. P.*; Asih, R.*; Yoon, S.*; Watanabe, Isao*; Nakajima, Kenji
JPS Conference Proceedings (Internet), 21, p.011007_1 - 011007_5, 2018/03
RbCuMoO is a one-dimensional quantum spin system with spin frustration. The magnetic ground state of this system has been expected to be incommensurate spin-singlet from a theoretical study. Furthermore, it was recently reported that this system exhibited ferroelectricity under a magnetic field. We carried out SR studies on this system to understand the magnetic properties. A slow muon spin relaxation due to nuclear dipoles is observed in the whole measured temperatures ranging from 0.06 K to 250 K, indicating that no magnetic ordering. The result suggests that the system shows a spin-singlet ground state. Furthermore, it was found that the distribution of the internal magnetic field were slightly enhanced below 10 K. This temperature dependence resembles that of the electric polarization observed in the magnetic field. It may indicate that some local anomaly of charge/spin related to the ferroelectricity is detected by a microscopic probe.
Abe, Shinichiro; Sato, Tatsuhiko
Meson, (47), p.34 - 39, 2018/03
Some researchers actively investigate secondary cosmic-ray muon radiography for imaging of large structures, detecting nuclear matter, and so on. The simulation is one of effective methods to estimate the required time for muon radiography or to optimize detection system. In this report, we introduce particle transport code PHITS and analytical model for estimating the atmospheric cosmic-ray spectra PARMA. Benchmark results are also shown. PHITS describes intensities of terrestrial muons in the ground well. PHITS also shows good agreement with measured data for particle generations from several interactions between muon and material. These results indicate the practicability of PHITS for simulation of muon radiography. PARMA reproduces cosmic-ray spectra on several spots well. Excellent agreement is seen between the measurements and PARMA for muon fluxes with large zenith angles and high energies, which are important for muon radiography.
Ito, Takashi; Higemoto, Wataru
KURRI-KR-202, p.42 - 45, 2015/03
no abstracts in English
Kaminaga, Masanori; Haga, Katsuhiro; Kinoshita, Hidetaka; Torii, Yoshikatsu; Hino, Ryutaro; Ikeda, Yujiro
Proceedings of ICANS-XVI, Volume 1, p.125 - 133, 2003/07
no abstracts in English
High-intensity Proton Accelerator Project Team
JAERI-Tech 2003-044, 788 Pages, 2003/03
This report presents the detail of the technical design of the acclerators for the High-Intensity Proton Accelerator Facility Project, J-PARC. The accelerator complex comprises a 400-MeV room-temperature linac (600-MeV superconducting linac), 3-GeV rapid-cycling synchrotron (RCS), and a 50-GeV synchrotron (MR). The 400-MeV beam is injected to the RCS, being accelerated to 3 GEV. The 1-MW beam thus produced is guided to the Materials Life Science Experimental Facility, with both the pulsed spallation neutron source and muon source. A part of the beam is transported to the MR, which provides the 0.75-MW beam to eithter the Nuclear and Fundamental Particle Experimental Facility or the Neutrino Production Target. On the other hand, the beam acclerated to 600 MeV by the superconducting linac is used for the Nuclear Waster Transmutation Experiment. In this way, this facility is unique, being multipurpose one, including many new inventions and Research and Development Results.
Kato, Mineo; Ito, Takeshi*; Sugai, Hiroyuki; Kawamura, Yoshinori; Hayashi, Takumi; Nishi, Masataka; Tanase, Masakazu; Matsuzaki, Teiichiro*; Ishida, Katsuhiko*; Nagamine, Kanetada*
Fusion Science and Technology, 41(3), p.859 - 862, 2002/05
JAERI has a plane to develop a compact tritium gas recycling system for fusion research. This system is also very attractive for the muon-catalyzed fusion (CF) research at RIKEN-RAL Muon Facility in UK. For the research, JAERI has produced high purity tritium gas of 1,500 Ci and transported it to the Facility. In the CF experiments, the tritium gas was diluted by the deuterium in an optional concentration and the used tritium gas was carried back by the tritium transport container developed to JAERI. If it is possible to recycle the diluted tritium gas, i.e., the used tritium gas is enriched in the experimental site, the CF experiments should be conducted efficiently. rom the above point of view, in this paper, we propose the compact tritium gas recycling system based on the gas chromatography that has already developed in JAERI and a proton conductor.
Sakamoto, Shinichi; Meigo, Shinichiro; Konno, Chikara; Harada, Masahide; Miyake, Yasuhiro*; Kasugai, Yoshimi; Muto, Suguru*; Fujimori, Satoru*; Ono, Takehiro; Ikeda, Yujiro
JAERI-Tech 2001-075, 168 Pages, 2001/12
no abstracts in English
Kato, Mineo; Kurosawa, Kiyoyuki; Sugai, Hiroyuki; Tanase, Masakazu; Matsuzaki, Teiichiro*; Ishida, Katsuhiko*; Nagamine, Kanetada*
KEK Proceedings 99-11, p.113 - 127, 1999/00
no abstracts in English