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Watanabe, Kenichi*; Sugai, Yusuke*; Hasegawa, Sota*; Tanaka, Seishiro*; Hitomi, Keitaro*; Nogami, Mitsuhiro*; Shinohara, Takenao; Su, Y. H.; Parker, J. D.*; Kockelmann, W.*
Scientific Reports (Internet), 14, p.25224_1 - 25224_13, 2024/10
Times Cited Count:1 Percentile:12.49(Multidisciplinary Sciences)Uchibori, Akihiro; Doda, Norihiro; Aoyagi, Mitsuhiro; Sonehara, Masateru; Sogabe, Joji; Okano, Yasushi; Takata, Takashi*; Tanaka, Masaaki; Enuma, Yasuhiro; Wakai, Takashi; et al.
Nuclear Engineering and Design, 413, p.112492_1 - 112492_10, 2023/11
Times Cited Count:4 Percentile:41.66(Nuclear Science & Technology)The ARKAIDA has been developed to realize automatic optimization of plant design from safety evaluation for the advanced reactors represented by a sodium-cooled fast reactor. ARKADIA-Design offers functions to support design optimization both in normal operating conditions and design basis events. The multi-level simulation approach by the coupled analysis such as neutronics, core deformation, core thermal hydraulics was developed as one of the main technologies. On the other hand, ARKAIDA-Safety aims for safety evaluation considering severe accidents. As a key technology, the numerical methods for in- and ex-vessel coupled phenomena during severe accidents in sodium-cooled fast reactors were tested through a hypothetical severe accident event. Improvement of the ex-vessel model and development of the AI technology to find best design solution have been started.
Niwa, Masakazu; Shimada, Koji; Sueoka, Shigeru; Fujita, Natsuko; Yokoyama, Tatsunori; Ogita, Yasuhiro; Fukuda, Shoma; Nakajima, Toru; Kagami, Saya; Ogata, Manabu; et al.
JAEA-Review 2023-017, 27 Pages, 2023/10
This report is a plan of research and development (R&D) on geosphere stability for long-term isolation of high-level radioactive waste (HLW) in Japan Atomic Energy Agency (JAEA), in fiscal year 2023. The objectives and contents in fiscal year 2023 are described in detail based on the JAEA 4th Medium- and Long-term Plan (fiscal years 2022-2028). In addition, the background of this research is described from the necessity and the significance for site investigation and safety assessment, and the past progress. The plan framework is structured into the following categories: (1) Development and systematization of investigation techniques, (2) Development of models for long-term estimation and effective assessment, (3) Development of dating techniques.
Kuroda, Kenta*; Arai, Yosuke*; Rezaei, N.*; Kunisada, So*; Sakuragi, Shunsuke*; Alaei, M.*; Kinoshita, Yuto*; Bareille, C.*; Noguchi, Ryo*; Nakayama, Mitsuhiro*; et al.
Nature Communications (Internet), 11, p.2888_1 - 2888_9, 2020/06
Times Cited Count:44 Percentile:82.49(Multidisciplinary Sciences)Abe, Mitsushi*; Bae, S.*; Beer, G.*; Bunce, G.*; Choi, H.*; Choi, S.*; Chung, M.*; da Silva, W.*; Eidelman, S.*; Finger, M.*; et al.
Progress of Theoretical and Experimental Physics (Internet), 2019(5), p.053C02_1 - 053C02_22, 2019/05
Times Cited Count:195 Percentile:99.42(Physics, Multidisciplinary)This paper introduces a new approach to measure the muon magnetic moment anomaly
and the muon electric dipole moment (EDM)
at the J-PARC muon facility. The goal of our experiment is to measure
and
using an independent method with a factor of 10 lower muon momentum, and a factor of 20 smaller diameter storage-ring solenoid compared with previous and ongoing muon g-2 experiments with unprecedented quality of the storage magnetic field. Additional significant differences from the present experimental method include a factor of 1000 smaller transverse emittance of the muon beam (reaccelerated thermal muon beam), its efficient vertical injection into the solenoid, and tracking each decay positron from muon decay to obtain its momentum vector. The precision goal for
is a statistical uncertainty of 450 parts per billion (ppb), similar to the present experimental uncertainty, and a systematic uncertainty less than 70 ppb. The goal for EDM is a sensitivity of
e
cm.
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:18 Percentile:98.46(Quantum Science & Technology)Ueno, Yasuhiro*; Aoki, Masaharu*; Fukao, Yoshinori*; Higashi, Yoshitaka*; Higuchi, Takashi*; Iinuma, Hiromi*; Ikedo, Yutaka*; Ishida, Katsuhiko*; Ito, Takashi; Iwasaki, Masahiko*; et al.
Hyperfine Interactions, 238(1), p.14_1 - 14_6, 2017/11
Times Cited Count:4 Percentile:87.69(Physics, Atomic, Molecular & Chemical)Strasser, P.*; Aoki, Masaharu*; Fukao, Yoshinori*; Higashi, Yoshitaka*; Higuchi, Takashi*; Iinuma, Hiromi*; Ikedo, Yutaka*; Ishida, Katsuhiko*; Ito, Takashi; Iwasaki, Masahiko*; et al.
Hyperfine Interactions, 237(1), p.124_1 - 124_9, 2016/12
Times Cited Count:8 Percentile:90.64(Physics, Atomic, Molecular & Chemical)Ogiwara, Norio; Hikichi, Yusuke; Namekawa, Yuya; Kamiya, Junichiro; Kinsho, Michikazu; Hatanaka, Kichiji*; Shima, Tatsushi*; Fukuda, Mitsuhiro*
Proceedings of 7th International Particle Accelerator Conference (IPAC '16) (Internet), p.2102 - 2104, 2016/06
Kamiya, Junichiro; Hikichi, Yusuke; Kinsho, Michikazu; Ogiwara, Norio; Fukuda, Mitsuhiro*; Hamatani, Noriaki*; Hatanaka, Kichiji*; Kamakura, Keita*; Takahisa, Keiji*
Journal of Vacuum Science and Technology A, 33(3), p.031605_1 - 031605_8, 2015/05
Times Cited Count:5 Percentile:20.29(Materials Science, Coatings & Films)For the vacuum systems of high-intensity beam accelerators, low radioactivation materials with good vacuum characteristics and high mechanical strength are required. The titanium alloy Ti-6Al-4V was investigated as a potential low activation vacuum material with high mechanical strength for the fabrication of vacuum components, particularly the flanges of beam pipes, in the J-PARC 3 GeV synchrotron. The dose rate of Ti-6Al-4V when irradiated by a 400 MeV proton was observed to decrease more rapidly than that of stainless steel. Furthermore, the generated radioactive isotopes were nuclides with relatively short half-lives. The outgassing rate of Ti-6Al-4V was the same as the typical value for stainless steel. Additionally, the hydrogen concentration in bulk Ti-6Al-4V was reduced to approximately 1 ppm by vacuum firing. These results indicate that Ti-6Al-4V is a good candidate for use as a low activation vacuum material with high mechanical strength.
Tokuhisa, Atsushi*; Arai, Junya*; Jochi, Yasumasa*; Ono, Yoshiyuki*; Kameyama, Toyohisa*; Yamamoto, Keiji*; Hatanaka, Masayuki*; Gerofi, B.*; Shimada, Akio*; Kurokawa, Motoyoshi*; et al.
Journal of Synchrotron Radiation, 20(6), p.899 - 904, 2013/11
Times Cited Count:5 Percentile:27.11(Instruments & Instrumentation)Kamiya, Junichiro; Ogiwara, Norio; Kinsho, Michikazu; Kamakura, Keita*; Hamatani, Noriaki*; Hatanaka, Kichiji*; Fukuda, Mitsuhiro*; Takahisa, Keiji*
Journal of the Vacuum Society of Japan, 56(5), p.167 - 171, 2013/05
no abstracts in English
Iwamoto, Yosuke; Fukuda, Mitsuhiro*; Sakamoto, Yukio; Tamii, Atsushi*; Hatanaka, Kichiji*; Takahisa, Keiji*; Nagayama, Keiichi*; Asai, Hiroaki*; Sugimoto, Kenji*; Nashiyama, Isamu*
Nuclear Technology, 173(2), p.210 - 217, 2011/02
Times Cited Count:35 Percentile:90.34(Nuclear Science & Technology)The 30
white neutron beam at RCNP facility has been characterized as a prove suitable for testing of single event effects (SEEs) in semiconductors in the neutron energy range from 1 to 300 MeV using the 392-MeV proton incident reaction on a 6.5-cm-thick tungsten target. The neutron spectrum in measurements were demonstrated to provide a neutron spectrum similar to the terrestrial one at sea level, but with an enhancement in the intensity of a factor of 1.5
10
. The average neutron intensity and spectrum from 10 to 300 MeV at RCNP were almost same as those at WNR. The calculated RCNP neutron flux using PHITS generally agreed with the measured RCNP data within a factor of two. As the neutron density per pulse for RCNP is 500 times lower than that for WNR, the pileup probability of single-event transient currents and false multiple-bit upsets is reduced. Such conditions at RCNP are suitable for accelerated SEE testing to get meaningful results in realistic time frame.
Ishiyama, Atsushi*; Ueda, Hiroshi*; Fukuda, Mitsuhiro*; Hatanaka, Kichiji*; Miyahara, Nobuyuki*; Yokota, Wataru; Kashima, Naoji*; Nagaya, Shigeo*
Denki Gakkai Kenkyukai Shiryo, Chodendo Oyo Denryoku Kiki Kenkyukai (ASC-10-33), p.83 - 88, 2010/06
Therapy of tumor using radiation, especially heavy particle, is one of the effective treatment for an aged person and a malignant solid tumor. In order to spread the radiation therapy, downsizing of accelerator is necessary for reduction of its vast costs of construction and running. The quality of high temperature superconductors is improving rapidly in recent years, which may lead to realization of the downsizing. This presentation describes a conceptual design of the superconducting cyclotron and its advantage comparing to other type of accelerators.
Imai, Nobuaki*; Jeong, S.-C.*; Oyaizu, Mitsuhiro*; Arai, Shigeaki*; Fuchi, Yoshihide*; Hirayama, Yoshikazu*; Ishiyama, Hironobu*; Miyatake, Hiroari; Tanaka, Masahiko*; Okada, Masashi*; et al.
Review of Scientific Instruments, 79(2), p.02A906_1 - 02A906_3, 2008/02
Times Cited Count:13 Percentile:49.97(Instruments & Instrumentation)KEKCB is an 18 GHz Electron Cyclotron Resonance (ECR) ion source and is a charge breeder device for converting mass-separated 1
radioactive ions to multi-ionized ones by utilizing an axial injection technique to the ECR plasma. It is a part of the Tokai Radioactive Ion Accelerator Complex (TRIAC) facility. Based on the developments so far, converting efficiencies for metal elements, such as barium and indium, and for gaseous elements, such as krypton and xenon, are improved to be 7
and 2
, respectively. And it is confirmed that the efficiency is nearly the constant for short-lived (t
1 sec) isotopes. Background ions mixed in the output beams are supressed to be 600 pps from 10
pps by applying all aluminum electrodes and high pressure pure-water cleanings.
Matsuda, Makoto; Takeuchi, Suehiro; Tsukihashi, Yoshihiro; Hanashima, Susumu; Abe, Shinichi; Osa, Akihiko; Ishizaki, Nobuhiro; Tayama, Hidekazu; Nakanoya, Takamitsu; Kabumoto, Hiroshi; et al.
Proceedings of 3rd Annual Meeting of Particle Accelerator Society of Japan and 31st Linear Accelerator Meeting in Japan, p.275 - 277, 2006/00
no abstracts in English
Fukuda, Mitsuhiro; Ito, Hisayoshi; Oshima, Takeshi; Saido, Masahiro; Tanaka, Atsushi
Charged Particle and Photon Interactions with Matter, p.813 - 859, 2003/11
An ion beam has been widely applied to a variety of research fields of materials, space, and bio-sciences. Notable results, which were hard to obtain in applications of a
ray and an electron beam, have been produced by the ion beam application. Ion beams interacting with matter have such superior properties as highly localized ionization and excitation, production of secondary particles, implantation of different atoms, and nuclear transmutation of constituent atoms. Skillful utilization of the ion beam properties makes remarkable progress in creation of new materials and precise investigation of matters. The ion beam irradiation research facility, TIARA, was established in 1993 at JAERI for extensive applications of ion beams. An accelerator complex provides light to heavy ion beams with a broad energy range from keV to GeV. Various ion beam technologies pioneering the ion beam applications have been developed at TIARA. In this paper, new applications of accelerated ion beams to material, space, and biological science and engineering carried out mainly at TIARA are reviewed.
Ga
N(0
x
1)Nakanishi, Yasuo*; Wakahara, Akihiro*; Okada, Hiroshi*; Yoshida, Akira*; Oshima, Takeshi; Ito, Hisayoshi; Shibata, Tomohiko*; Tanaka, Mitsuhiro*
Physica Status Solidi, 0(7), p.2623 - 2626, 2003/07
In our previous study, it was reported that Eu-doped Nitride semiconductors show luminescence propetires. In this study, we investigate the relationship between luminescence properties and Al composition using Al
Ga
N(0
x
1). Al
Ga
N were grown using OMVPE. Eu atoms were doped into the samples by ion implantation (200keV). After implantation, the samples were annealed to remove residual damege. Luminescence propreties of the samples were measured using photoluminescence and cathodeluminescence. As a result, luminescence at 621 nm which relates 4f-4f transition were observed for all samples (x=0 to 1). As for intensity, samples with x=0.5 show the strongest luminescence. This result can be interpreted in terms of the internal stress of crystals by the existence of Al atoms.
Fukuda, Mitsuhiro; Arakawa, Kazuo; Yokota, Wataru; Okumura, Susumu; Agematsu, Takashi; Kamiya, Tomihiro; Mizuhashi, Kiyoshi; Nara, Takayuki; Saito, Yuichi; Ishii, Yasuyuki; et al.
AIP Conference Proceedings 600, p.189 - 191, 2001/00
A new project aiming for a breakthrough in biotechnology and materials science has been proposed at TIARA(Takasaki Ion Accelerators for Advanced Radiation Application) facilities of JAERI. Heavy ion beams with an energy of more than a hundred MeV/n will contribute to remarkable progress in breeding of plants and development of new materials. We have started designing a new superconducting AVF cyclotron with a bending limit of 900 and a focusing limit of 300. The cyclotron magnet is being designed to cope with acceleration of both the heavy ions and 300 MeV protons.
Fukuda, Mitsuhiro; Arakawa, Kazuo; Yokota, Wataru; Okumura, Susumu; Agematsu, Takashi; Kamiya, Tomihiro; Mizuhashi, Kiyoshi; Nara, Takayuki; Saito, Yuichi; Ishii, Yasuyuki; et al.
Proceedings of 13th Symposium on Accelerator Science and Technology, p.71 - 73, 2001/00
A new project bringing about a breakthrough in biotechnology and materials science has been proposed at JAERI (Japan Atomic Energy Research Institute). Heavy ion beams with energy of more than 100 MeV/n are expected to contribute to remarkable progress in breeding of plants and development of new materials. Design studies of a superconducting AVF cyclotron with a K number of 900 has been started to meet requirements for the researches. A four-sector, four-dee cyclotron is being designed to cope with acceleration of both the heavy ions and 300 MeV protons.