Spin model of O-based magnet in a nanoporous metal complex

Soda, Minoru*; Homma, Yuki*; Takamizawa, Satoshi*; Kawamura, Seiko; Nakajima, Kenji; Masuda, Takatsugu*

Journal of the Physical Society of Japan, 85(3), p.034717_1 - 034717_9, 2016/03

https://doi.org/10.7566/JPSJ.85.034717

Inelastic neutron scattering experiments are performed on the nanoporous metal complex Cu--1,4-cyclohexanedicarboxylic acid (Cu-CHD) adsorbing O molecules to identify the spin model of the O-based magnet realized in the host complex. It is found that the magnetic excitations of Cu-CHDs adsorbing low- and high-concentration O molecules are explained by different spin models, the former by spin dimers and the latter by spin trimers. By using the obtained parameters and by assuming that the levels of the group of the highest energy states are reduced because of the nonnegligible spin dependence of the molecular potential of oxygen, the magnetization curves are explained quantitatively.

Actinide-handling experience for training and education of future expert under J-ACTINET

Osaka, Masahiko; Konashi, Kenji*; Hayashi, Hirokazu; Li, D.*; Homma, Yoshiya*; Yamamura, Tomoo*; Sato, Isamu; Miwa, Shuhei; Sekimoto, Shun*; Kubota, Takumi*; et al.

Proceedings of International Conference on Toward and Over the Fukushima Daiichi Accident (GLOBAL 2011) (CD-ROM), 5 Pages, 2011/12

Summer schools for future experts have successfully been completed under Japan Actinide Network (J-ACTINET) for the purpose of development of human resources who are expected to be engaged in every areas of actinide-research/engineering. The first summer school was held in Ibaraki-area in August 2009, followed by the second one in Kansai-area in August 2010. Two summer schools have focused on actual experiences of actinides in actinide-research fields for university students and young researchers/engineers as an introductory course of actinide-researches. Several quasi actinide-handling experiences at the actinide-research fields have attracted attentions of participants at the first school in Ibaraki-area. The actual experiments using actinides-containing solutions have been carried out at the second school in Kansai-area. Future summer schools will be held every year for the sustainable human resource development in various actinide-research fields.

Azimuthal correlations of electrons from heavy-flavor decay with hadrons in and Au+Au collisions at = 200 GeV

Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Aramaki, Y.*; et al.

Physical Review C, 83(4), p.044912_1 - 044912_16, 2011/04

https://doi.org/10.1103/PhysRevC.83.044912

Measurements of electrons from the decay of open-heavy-flavor mesons have shown that the yields are suppressed in Au+Au collisions compared to expectations from binary-scaled collisions. Here we extend these studies to two particle correlations where one particle is an electron from the decay of a heavy flavor meson and the other is a charged hadron from either the decay of the heavy meson or from jet fragmentation. These measurements provide more detailed information about the interaction between heavy quarks and the quark-gluon matter. We find the away-side-jet shape and yield to be modified in Au+Au collisions compared to collisions.

Characteristics of water flow distribution in TBM side wall

Yoshikawa, Akira; Tanigawa, Hisashi; Seki, Yohji; Hirose, Takanori; Tsuru, Daigo; Ezato, Koichiro; Yokoyama, Kenji; Nishi, Hiroshi; Suzuki, Satoshi; Tanzawa, Sadamitsu; et al.

JAEA-Technology 2009-077, 23 Pages, 2010/03

JAEA-Technology-2009-077.pdf:2.62MB

In the side wall of TBM, parallel flow channels are considered. In the cooling channels structure, the flow distribution probably arises from the pressure drop in the channels. The purpose of this study is to clarify the water flow distribution in the side wall and design the cooling channels structure so that structural material of the side wall can be kept under the allowable temperature. The structural material for assumed flow rates and the flow distribution were estimated, and then the cooling channels structure was designed. The design was verified using the mockup made of the vinyl chloride pipe. For the verified design, the mockup made of F82H is manufactured, and the water flow distribution and the pressure drop were measured. It was found that the heat removal capability was sufficient in this design. From these results, the design for the cooling channels structure in the side wall is established so that enough water flow to cool the structural material is kept.

Element and orbital-specific observation of two-step magnetic transition in NpNiGa; X-ray magnetic circular dichroism study

Okane, Tetsuo; Okochi, Takuo*; Inami, Toshiya; Takeda, Yukiharu; Fujimori, Shinichi; Kawamura, Naomi*; Suzuki, Motohiro*; Tsutsui, Satoshi*; Yamagami, Hiroshi; Fujimori, Atsushi; et al.

Physical Review B, 80(10), p.104419_1 - 104419_7, 2009/09

https://doi.org/10.1103/PhysRevB.80.104419

Neutrino-nucleus reactions based on recent advances in shell-model calculations

Suzuki, Toshio*; Chiba, Satoshi; Yoshida, Takashi*; Higashijima, Koji*; Homma, Michio*; Kajino, Toshitaka*; Otsuka, Takaharu*

Nuclear Physics A, 805(2), p.579 - 581, 2008/02

Neutrino-nucleus reactions on C and He are studied based on new shell model Hamiltonians. The cross sections are found to be enhanced compared with those obtained by conventional Hamiltonians. The production yield of Li and B during supernova explosions are pointed out to be enhanced, and a possibility of determining the neutrino mixing angle is discussed in case of neutrino oscillations. Neutrino induced reactions on Fe and Ni isotopes are also studied based on recent advances in shell model calculations in the -shell. The reaction crowds sections are found to be enhanced compared with those obtained by a modified KB3 Hamiltonian.

Test strategy and development achievements of ITER solid breeder test blanket modules in Japan

Enoeda, Mikio; Hirose, Takanori; Tanigawa, Hisashi; Tsuru, Daigo; Suzuki, Satoshi; Ezato, Koichiro; Hatano, Toshihisa; Nomoto, Yasunobu; Nishi, Hiroshi; Homma, Takashi; et al.

Proceedings of 21st IAEA Fusion Energy Conference (FEC 2006) (CD-ROM), 8 Pages, 2007/03

http://www-naweb.iaea.org/napc/physics/FEC/FEC2006/html/node303.htm#59769

This paper presents progresses of the test strategy development, design and supporting R&Ds of solid breeder Test Blanket Modules (TBMs) in Japan. Japan is proposing to test its unique designs of Water Cooled Solid Breeder (WCSB) TBM and Helium Cooled Solid Breeder (HCSB) TBM from the beginning of the ITER operation. As for the design work, structure design showed steady progress and clarified detailed structure taking into account the fabrication procedure. As for supporting R&Ds, the corrosion characteristics of the structural material by high temperature and pressure water was clarified as one of critical structure integrity issues. Also, important design data of the breeder pebble bed has been clarfied. Along with the development progress, the test strategy has been investigated to obtain the most effective results of TBM test program.

Estimation of pitting damage induced by cavitation impacts

Soyama, Hitoshi*; Futakawa, Masatoshi; Homma, Kana*

Journal of Nuclear Materials, 343(1-3), p.116 - 122, 2005/08

https://doi.org/10.1016/j.jnucmat.2004.11.016

In order to estimate life time of the mercury target vessel of spallation neutron source which will be subjected to cavitation impacts, prediction methods of pitting damage induced by the cavitation impact were proposed. It is very important to estimate incubation time, in which plastic deformation occurs without mass loss, because the thickness of vessel is very thin. In the present paper, two estimation methods were proposed. One of them is estimatiion from erosion test of severely damaged specimen by plotting the mass loss as a function of exposure time to cavitation on the logarithmic scales. Another method is the observation method of plastic deformation pits on damaged surface at very early period in incubation stage.

U Mssbauer study on the 5f-quadrupoles in uranium-based intermetallics

Tsutsui, Satoshi*; Nakada, Masami; Nasu, Saburo*; Homma, Tetsuo*; Tokiwa, Yoshifumi; Aoki, Dai*; Wisniewski, P.*; Haga, Yoshinori; Onuki, Yoshichika

Hyperfine Interactions, 141/142(1-4), p.237 - 242, 2002/06

https://doi.org/10.1023/A:1021281315015

We have determined the distribution of the 5f-quadrupoles and detected the 5f-quadrupole order in the uranium intermetallics, uranium dipnictides and UPd, with Mo"ssbauer spectroscopy. We have declared that the distribution of the 5f-quadrupoles depends on the magnetic sequence in uranium dipnictides. The distribution of the 5f-quadrupole is spherical in UBi, while those are oblate within c-plane in UP, UAs and USb. We have observed the sudden drop of the recoil-free fraction above the transition temperature of the quadrupole order in UPd. The present result suggests the change of the phonon states due to the quadrupole order in this compound.

U Mssbauer study on the magnetic properties of uranium-based heavy fermion superconductors

Tsutsui, Satoshi; Nakada, Masami; Nasu, Saburo*; Haga, Yoshinori; Homma, Tetsuo; Yamamoto, Etsuji; Okuni, Hitoshi*; Onuki, Yoshichika

Hyperfine Interactions, 126(1-4), p.335 - 340, 2000/07

https://doi.org/10.1023/A:1012626913681

no abstracts in English