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He neutron spin filter at J-PARCOkudaira, Takuya; Oku, Takayuki; Ino, Takashi*; Hayashida, Hirotoshi*; Kira, Hiroshi*; Sakai, Kenji; Hiroi, Kosuke; Takahashi, Shingo*; Aizawa, Kazuya; Endo, Hitoshi*; et al.
Nuclear Instruments and Methods in Physics Research A, 977, p.164301_1 - 164301_8, 2020/10
Times Cited Count：18 Percentile：88.97(Instruments & Instrumentation)Torigoe, Shuhei*; Hattori, Takayuki*; Kodama, Katsuaki; Honda, Takashi*; Sagayama, Hajime*; Ikeda, Kazutaka*; Otomo, Toshiya*; Nitani, Hiroaki*; Abe, Hitoshi*; Murakawa, Hiroshi*; et al.
Physical Review B, 98(13), p.134443_1 - 134443_7, 2018/10
Times Cited Count：13 Percentile：51.13(Materials Science, Multidisciplinary)Nakajima, Kenji; Kawakita, Yukinobu; Ito, Shinichi*; Abe, Jun*; Aizawa, Kazuya; Aoki, Hiroyuki; Endo, Hitoshi*; Fujita, Masaki*; Funakoshi, Kenichi*; Gong, W.*; et al.
Quantum Beam Science (Internet), 1(3), p.9_1 - 9_59, 2017/12
The neutron instruments suite, installed at the spallation neutron source of the Materials and Life Science Experimental Facility (MLF) at the Japan Proton Accelerator Research Complex (J-PARC), is reviewed. MLF has 23 neutron beam ports and 21 instruments are in operation for user programs or are under commissioning. A unique and challenging instrumental suite in MLF has been realized via combination of a high-performance neutron source, optimized for neutron scattering, and unique instruments using cutting-edge technologies. All instruments are/will serve in world-leading investigations in a broad range of fields, from fundamental physics to industrial applications. In this review, overviews, characteristic features, and typical applications of the individual instruments are mentioned.
Sakasai, Kaoru; Sato, Setsuo*; Seya, Tomohiro*; Nakamura, Tatsuya; To, Kentaro; Yamagishi, Hideshi*; Soyama, Kazuhiko; Yamazaki, Dai; Maruyama, Ryuji; Oku, Takayuki; et al.
Quantum Beam Science (Internet), 1(2), p.10_1 - 10_35, 2017/09
Neutron devices such as neutron detectors, optical devices including supermirror devices and 
He neutron spin filters, and choppers are successfully developed and installed at the Materials Life Science Facility (MLF) of the Japan Proton Accelerator Research Complex (J-PARC), Tokai, Japan. Four software components of MLF computational environment, instrument control, data acquisition, data analysis, and a database, have been developed and equipped at MLF. MLF also provides a wide variety of sample environment options including high and low temperatures, high magnetic fields, and high pressures. This paper describes the current status of neutron devices, computational and sample environments at MLF.
Ikawa, Nozomu*; Mukai, Yoichi*; Nishida, Akemi; Hamamoto, Takuji*; Kano, Toshiya*; Ota, Toshiro*; Nakamura, Naohiro*; Komuro, Masato*; Takeuchi, Masato*
Proceedings of 12th International Conference on Shock and Impact Loads on Structures (SI 2017) (USB Flash Drive), p.259 - 268, 2017/06
Accidental actions on building structures involve impact and explosion loads. The design loads due to impact are determined by experiment data, impact simulation and energetics approach. These loads are presented in the form of load-time (F-t) curves caused by collision and explosion. It is assumed that the structure is rigid and immovable and that impacting body absorbs all the energy (i.e., hard impact condition is supposed), because this assumption gives conservative results in general. Responses of individual structural members directly-subjected to an impulsive load are evaluated. These responses are classified into three types; impulsive response, dynamic response, and quasi-static response. The maximum responses are basically estimated by direct integration method with a single-degree-of-freedom (SDOF) model. The procedure of the SDOF modelling based on the classification of types of members and failure modes is proposed in AIJ guideline.
Tonegawa, Takashi*; Okamoto, Kiyomi*; Hikihara, Toshiya*; Sakai, Toru
Journal of Physics; Conference Series, 683(1), p.012039_1 - 012039_7, 2016/02
Times Cited Count：2 Percentile：68.55(Materials Science, Multidisciplinary)Employing mainly numerical methods, we explore the ground-state phase diagram of an anisotropic S=1/2 ladder, in which leg interactions are uniform and isotropic, while rung interactions are alternating and have a common Ising-type anisotropy. We determine the phase diagrams in some typical cases.
Si observed by X-ray absorption spectroscopyNakai, Hirohito*; Ebihara, Takao*; Tsutsui, Satoshi*; Mizumaki, Masaichiro*; Kawamura, Naomi*; Michimura, Shinji*; Inami, Toshiya; Nakamura, Toshiyuki*; Kondo, Akihiro*; Kindo, Koichi*; et al.
Journal of the Physical Society of Japan, 82(12), p.124712_1 - 124712_5, 2013/12
Times Cited Count：9 Percentile：52.73(Physics, Multidisciplinary)The temperature and magnetic field dependences of Yb valence were observed in the heavy fermion compoundYbRhSi by X-ray absorption spectroscopy. The measurements revealed that the Yb valence decreases with decreasing temperature in the range from 200 to 2 K and increases with increasing magnetic field in the range from 0 to 33 T without showing an abrupt change in the Yb valence. The Yb valence is in the range from 2.92 to 2.96 depending on temperature and magnetic field. With respect to the valence being 2.92 at 0 T and 2.93 at 33 T in 2 K, YbRhSi is a valence fluctuation compound and does not reach the integer trivalent state at high magnetic field. These results endorse the conventional knowledge that the valence of Yb is very close to the integer value of 3+, decreases with decreasing temperature, and becomes closer to 3+ with increasing magnetic field.
Kai, Tetsuya; Maekawa, Fujio; Oshita, Hidetoshi*; Sato, Hirotaka; Shinohara, Takenao; Oi, Motoki; Harada, Masahide; Uno, Shoji*; Otomo, Toshiya*; Kamiyama, Takashi*; et al.
Physics Procedia, 43, p.111 - 120, 2013/00
Times Cited Count：20 Percentile：98.23(Physics, Applied)A neutron imaging instrument is in construction at the pulsed neutron source of J-PARC. Some demonstration experiments in NOBORU/J-PARC have carried. To explore widespread applications of the newly built instruments it is indispensable to indicate the range of coverage of this technique. In the presentation, the authors describe the results of some of demonstration measurements, and then compare all elements with the values obtained by multiplying peak cross section and peak widths of neutron resonances in evaluated nuclear data libraries. This value is expected to be a good measure to exhibit visibility of each element in this technique.
Nakagawa, Masahiro; Nojima, Shun; Fujii, Katsutoshi; Shishido, Nobuhito; Sakai, Toshiya; Umehara, Takashi; Shimizu, Isamu
Hoken Butsuri, 47(3), p.189 - 193, 2012/10
It is essential to wear an air-purifying respirator in the radiation works in a contaminated atmosphere. A breath-responsive-powered air-purifying respirator (BR-PAPR) has been recently developed. However, no research has yet been conducted to determine the protection factor (PF) of the BR-PAPR in actual workplaces. In this study, the PFs of the BR-PAPR were measured by a man-test apparatus and compared with those of a non-powered full face mask. The PFs were measured under three different situations; normal wearing condition, clogging the filter and leaving a gap between the face and the mask. Under these situations, it was found that the PFs of the BR-PAPR are higher than those of the non-powered full face mask. PFs greater than 4000 were obtained for 95% of the subjects who wear the BR-PAPR, and PFs over 6667, the upper limit of the man-test apparatus, were obtained for 49% of them. The questionnaire survey was conducted for workers. The results showed that the workers feel a reduced burden when they wear the BR-PAPR. The results of this study showed high protection performance and operation efficiency of the BR-PAPR.
Sakai, Hiroshi*; Umemori, Kensei*; Takahashi, Takeshi*; Furuya, Takaaki*; Shinoe, Kenji*; Ishii, Atsushi*; Sawamura, Masaru; Muto, Toshiya*
Proceedings of 7th Annual Meeting of Particle Accelerator Society of Japan (DVD-ROM), p.173 - 176, 2010/08
We are developing the superconducting (SC) cavity for Energy Recovery Linac (ERL) in Japan. In order to survey the electron emission and the heating spot of the cavity inner surface in detail, cavity diagnostics with the rotating mapping system was applied. Two types of sensors, one of which was the carbon resistor and the other was the Si PIN photo diode, were set to detect the temperature rise and electron emission. By rotating the sensor arrays around the cavity axis, a lot of information was obtained all over the cavity surface in detail. This paper reports the results of vertical tests by using this rotating mapping system with the single-cell and 9-cell Nb ERL cavity.
Muto, Toshiya*; Umemori, Kensei*; Sakai, Hiroshi*; Sawamura, Masaru; Shinoe, Kenji*; Furuya, Takaaki*
Proceedings of 7th Annual Meeting of Particle Accelerator Society of Japan (DVD-ROM), p.840 - 842, 2010/08
Energy Recovery Linac (ERL) for future light source has been developed by KEK, JAEA, ISSP and other institutes in Japan. An input coupler must feed high power, which is estimated about 20 kW for 20 MV/m ERL operation, into the main linac superconducting cavities. Because the input coupler induced an asymmetric electromagnetic field in the cavity, accelerating TM010 mode produce a transverse kick similar to higher order modes. Using CST Microwave-Studio (MW-Studio), we calculated the transverse kick of accelerating mode induced by the input coupler. In case of the on crest acceleration, the transverse kick by the transverse electric field and magnetic field are small as compared with the accelerating voltage. We also calculated the dependence with various inserted position of the coupler. In this paper, we will report the calculation of transverse kick and an arrangement of cavities to reduce the transverse kick.
Sakanaka, Shogo*; Akemoto, Mitsuo*; Aoto, Tomohiro*; Arakawa, Dai*; Asaoka, Seiji*; Enomoto, Atsushi*; Fukuda, Shigeki*; Furukawa, Kazuro*; Furuya, Takaaki*; Haga, Kaiichi*; et al.
Proceedings of 1st International Particle Accelerator Conference (IPAC '10) (Internet), p.2338 - 2340, 2010/05
Future synchrotron light source using a 5-GeV energy recovery linac (ERL) is under proposal by our Japanese collaboration team, and we are conducting R&D efforts for that. We are developing high-brightness DC photocathode guns, two types of cryomodules for both injector and main superconducting (SC) linacs, and 1.3 GHz high CW-power RF sources. We are also constructing the Compact ERL (cERL) for demonstrating the recirculation of low-emittance, high-current beams using above-mentioned critical technologies.
Al
Inami, Toshiya; Terada, Noriki*; Kitazawa, Hideaki*; Sakai, Osamu*
Journal of Physics; Conference Series, 200, p.032022_1 - 032022_4, 2010/02
Times Cited Count：0 Percentile：0.00(Materials Science, Multidisciplinary)AlInami, Toshiya; Terada, Noriki*; Kitazawa, Hideaki*; Sakai, Osamu*
Journal of the Physical Society of Japan, 78(8), p.084713_1 - 084713_5, 2009/08
Times Cited Count：14 Percentile：60.22(Physics, Multidisciplinary)CMatsumura, Takeshi*; Inami, Toshiya; Kosaka, Masashi*; Kato, Yoshiaki*; Inukai, Takaki*; Ochiai, Akira*; Nakao, Hironori*; Murakami, Yoichi*; Katano, Susumu*; Suzuki, Hiroyuki*
Journal of the Physical Society of Japan, 77(10), p.103601_1 - 103601_4, 2008/10
Times Cited Count：14 Percentile：62.42(Physics, Multidisciplinary)Sakanaka, Shogo*; Ago, Tomonori*; Enomoto, Atsushi*; Fukuda, Shigeki*; Furukawa, Kazuro*; Furuya, Takaaki*; Haga, Kaiichi*; Harada, Kentaro*; Hiramatsu, Shigenori*; Honda, Toru*; et al.
Proceedings of 11th European Particle Accelerator Conference (EPAC '08) (CD-ROM), p.205 - 207, 2008/06
Future synchrotron light sources based on the energy-recovery linacs (ERLs) are expected to be capable of producing super-brilliant and/or ultra-short pulses of synchrotron radiation. Our Japanese collaboration team is making efforts for realizing an ERL-based hard X-ray source. We report recent progress in our R&D efforts.
Shinohara, Takenao; Sakai, Motonobu*; Kawakita, Yukinobu; Otomo, Toshiya*; Imai, Hideto*; Aoki, Tsutomu*; Amemiya, Kazuki*
no journal, ,
no abstracts in English
Furutani, Misa; Aoyagi, Hiroyuki*; Shirato, Yoshihiro; Nojima, Shun; Nakagawa, Masahiro; Otsuka, Yoshikazu; Niinuma, Shinichi*; Sakai, Toshiya; Muto, Yasushi; Nanri, Tomohiro; et al.
no journal, ,
no abstracts in English
Asano, Shiro*; Okuyama, Toshihisa*; Ejiri, Mitsuru*; Mizumaki, Shoichi*; Mochida, Tsutomu*; Hamada, Takashi*; Araki, Takao*; Hayakawa, Atsuro*; Sagawa, Keiich*; Kai, Toshiya*; et al.
no journal, ,
no abstracts in English
Ejiri, Mitsuru*; Asano, Shiro*; Omori, Junji*; Okuyama, Toshihisa*; Takahashi, Nobuji*; Yamada, Masahiro*; Araki, Takao*; Kai, Toshiya*; Shibama, Yusuke; Masaki, Kei; et al.
no journal, ,
In the operation of Tokamak device, such loads as electromagnetic and seismic are assumed to be imposed on the vacuum vessel (VV), and not a little thermal expansion takes place when VV is baked. The gravity support (GS) has to support the loads described above in addition to the dead weight of VV including in-vessel components and compensate deformation. The GS is equipped with leaf spring that has both stiffness and flexibility. In this study, the FEM analysis-based design and assembly procedure of the GS is reported. The manufacturing process of GS components is also reported with trial manufacturing results.
