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Murase, Kiyoka*; Kataoka, Ryuho*; Nishiyama, Takanori*; Nishimura, Koji*; Hashimoto, Taishi*; Tanaka, Yoshimasa*; Kadokura, Akira*; Tomikawa, Yoshihiro*; Tsutsumi, Masaki*; Ogawa, Yasunobu*; et al.
Journal of Space Weather and Space Climate (Internet), 12, p.18_1 - 18_16, 2022/06
Times Cited Count：1 Percentile：20.65(Astronomy & Astrophysics)We identified two energetic electron precipitation (EEP) events during the growth phase of moderate substorms and estimated the mesospheric ionization rate for an EEP event for which the most comprehensive dataset from ground-based and space-born instruments was available. The mesospheric ionization signature reached below 70 km altitude and continued for ~15 min until the substorm onset, as observed by the PANSY radar and imaging riometer at Syowa Station in the Antarctic region. We also used energetic electron flux observed by the Arase and POES 15 satellites as the input for the air-shower simulation code PHITS to quantitatively estimate the mesospheric ionization rate. Combining the cutting-edge observations and simulations, we shed new light on the space weather impact of the EEP events during geomagnetically quiet times, which is important to understand the possible link between the space environment and climate.
Theis, C.*; Carbonez, P.*; Feldbaumer, E.*; Forkel-Wirth, D.*; Jaegerhofer, L.*; Pangallo, M.*; Perrin, D.*; Urscheler, C.*; Roesler, S.*; Vincke, H.*; et al.
EPJ Web of Conferences, 153, p.08018_1 - 08018_5, 2017/09
Times Cited Count：0 Percentile：0.03(Nuclear Science & Technology)At CERN, gas-filled ionization chambers PTW-34031 (PMI) are commonly used in radiation fields including neutrons, protons and 
-rays. A response function for each particle is calculated by the radiation transport code FLUKA. To validate a response function to high energy neutrons, benchmark experiments with quasi mono-energetic neutrons have been carried out at RCNP, Osaka University. For neutron irradiation with energies below 200 MeV, very good agreement was found comparing the FLUKA simulations and the measurements. In addition it was found that at proton energies of 250 and 392 MeV, results calculated with neutron sources underestimate the experimental data due to a non-negligible gamma component originating from the target 
Li(p,n)Be reaction.
Ikeda, Yoshitaka; Okano, Fuminori; Sakasai, Akira; Hanada, Masaya; Akino, Noboru; Ichige, Hisashi; Kaminaga, Atsushi; Kiyono, Kimihiro; Kubo, Hirotaka; Kobayashi, Kazuhiro; et al.
Nihon Genshiryoku Gakkai Wabun Rombunshi, 13(4), p.167 - 178, 2014/12
The JT-60U torus was disassembled so as to newly install the superconducting tokamak JT-60SA torus. The JT-60U used the deuterium for 18 years, so the disassembly project of the JT-60U was the first disassembly experience of a fusion device with radioactivation in Japan. All disassembly components were stored with recording the data such as dose rate, weight and kind of material, so as to apply the clearance level regulation in future. The lessons learned from the disassembly project indicated that the cutting technologies and storage management of disassembly components were the key factors to conduct the disassembly project in an efficient way. After completing the disassembly project, efforts have been made to analyze the data for characterizing disassembly activities, so as to contribute the estimation of manpower needs and the radioactivation of the disassembly components on other fusion devices.
Ikeda, Yoshitaka; Okano, Fuminori; Hanada, Masaya; Sakasai, Akira; Kubo, Hirotaka; Akino, Noboru; Chiba, Shinichi; Ichige, Hisashi; Kaminaga, Atsushi; Kiyono, Kimihiro; et al.
Fusion Engineering and Design, 89(9-10), p.2018 - 2023, 2014/10
Times Cited Count：2 Percentile：16.35(Nuclear Science & Technology)Disassembly of the JT-60U torus was started in 2009 after 18-years D
operations, and was completed in October 2012. The JT-60U torus was featured by the complicated and welded structure against the strong electromagnetic force, and by the radioactivation due to D-D reactions. Since this work is the first experience of disassembling a large radioactive fusion device in Japan, careful disassembly activities have been made. About 13,000 components cut into pieces with measuring the dose rates were removed from the torus hall and stored safely in storage facilities by using a total wokers of 41,000 person-days during 3 years. The total weight of the disassembly components reached up to 5,400 tons. Most of the disassembly components will be treated as non-radioactive ones after the clearance verification under the Japanese regulation in future. The assembly of JT-60SA has started in January 2013 after this disassembly of JT-60U torus.
Horie, Akira*; Tomita, Takeo*; Saiki, Asako*; Kono, Hidetoshi; Taka, Hikari*; Mineki, Reiko*; Fujimura, Tsutomu*; Nishiyama, Chiharu*; Kuzuyama, Tomohisa*; Nishiyama, Makoto*
Nature Chemical Biology, 5(9), p.673 - 679, 2009/09
Times Cited Count：43 Percentile：67.4(Biochemistry & Molecular Biology)Yoshida, Ayako*; Tomita, Takeo*; Kono, Hidetoshi; Fushinobu, Shinya*; Kuzuyama, Tomohisa*; Nishiyama, Makoto*
FEBS Journal, 276(11), p.3124 - 3136, 2009/06
Times Cited Count：15 Percentile：31.46(Biochemistry & Molecular Biology)
Ge spectrometer for neutron capture cross section measurementsOshima, Masumi; Hori, Junichi*; Harada, Hideo; Furutaka, Kazuyoshi; Koizumi, Mitsuo; Kitatani, Fumito; Toh, Yosuke; Kimura, Atsushi; Nakamura, Shoji; Igashira, Masayuki; et al.
Proceedings of International Conference on Nuclear Data for Science and Technology (ND 2007), Vol.1, p.603 - 606, 2008/05
Neutron capture cross sections of minor actinides and long-lived fission products are important for the R&D of innovative nuclear reactors. However, those data are rather poor both in quality and in quantity at present. Thus, we have started projects for neutron cross section measurements. We will construct an innovative -ray spectrometer consisting of Ge crystals and BGO shields. The neutron cross section measurements will be done at KUR linac and JAEA JRR-3M facilities, which will be extended at the high-intensity neutron source at J-PARC.
Nishiyama, Satoshi*; Uehara, Shinichi*; Yano, Takao*; Saito, Ryuhei*; Uchida, Masahiro; Sawada, Atsushi; Takebe, Atsuji
JNC TY8400 2005-007, 70 Pages, 2005/03
JNC-TY8400-2005-007.pdf:2.24MB
None
-sticking phenomena in muon catalyzed fusion for a high density D-T mixture with 30% tritium concentrationNagamine, Kanetada*; Matsuzaki, Teiichiro*; Ishida, Katsuhiko*; *; *; *; Miyake, Yasuhiro*; *; *; *; et al.
Muon Catal. Fusion, 5-6, p.289 - 295, 1991/00
no abstracts in English
Kawashima, Masatoshi*; *; *; *
PNC TN941 79-236, 238 Pages, 1979/12
This report describes the analysis of core nuclear characteristics of "Joyo" which were measured at the start up test. This report includes the following analyses; (1)Minimum Critical (2)Control Rod Worth (3)Sodium Void Reactivity (4)Fuel Subassembly Worth (5)Reaction Rate Distributions. The calculations were done by using JAERI-FAST-2 set (70 group). One of the purposes of this analysis was to confirm the validity of the 3-D Hex-Z model with diffusion theory. Followings are main results; (1)C/E value for K
was 1.0044 in the minimum critical core. (2)C/E values of control rods worth were 0.97
1.03. (3)The analysis of sodium void effect for single channel showed that the C/E values were 0.81.0 in the core region and 1.3 at the blanket-core boundary with homogeneous model. The diffusion calculations with JFS-2 set showed good agreement between measured and calculated data. (4)The calculated substitution reactivity worth between core S/A and blanket S/A at the core periphery agreed well with the measured ones (C/E = 0.951.05). The calculated substitution worth between Na channel and various S/A's generally overestimated the measured ones. (core fuel 
Na at the center C/E = 1.1 1.2, blanket fuel 
Na at 5F1 C/E - 1.31.5) (5)The analyses of the reaction rate traverses were done by the 3-D Hex-Z model with 8 group diffusion theory. C/E values of the central spectral indices for F
/F
, F
/F were 0.99 and 0.95 respectively. It was confirmed that 3D Hex-Z model was very useful to calculate whole core power distributions including the flux-tilt by the control rod insertion.
Np neutron capture cross sectionMizumoto, Motoharu; Oshima, Masumi; Koizumi, Mitsuo; Toh, Yosuke; Kimura, Atsushi; Harada, Hideo; Furutaka, Kazuyoshi; Kitatani, Fumito; Nakamura, Shoji; Igashira, Masayuki*; et al.
no journal, ,
Neutron capture cross section measurements of minor actinide nuclei have been carried out using a 4 Ge spectrometer. In the meeting, preliminary results of Np capture cross sections measured at the KUR electron linac TOF facility are reported.
-ray spectroscopies on TOF experimentsKimura, Atsushi; Furutaka, Kazuyoshi; Toh, Yosuke; Hori, Junichi*; Koizumi, Mitsuo; Mizumoto, Motoharu*; Nishiyama, Jun*; Oshima, Masumi
no journal, ,
no abstracts in English
