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Ikegami, Masanori*; Ueno, Akira
Proceedings of 18th Meeting of the International Collaboration on Advanced Neutron Sources (ICANS-18) (CD-ROM), p.61 - 69, 2007/04
The beam commissioning of J-PARC linac has been started since November 2006 with the reduced beam energy of 181 MeV. This series of beam commissioning is to be continued until June 2007, and about three fourths of it has been completed as of April 2007. In this paper, we present commissioning results obtained to date together with the commissioning problems and issues experienced so far. We also briefly touch upon the commissioning plans hereafter.
in JSNSMaekawa, Fujio; Oikawa, Kenichi; Harada, Masahide; Kai, Tetsuya; Meigo, Shinichiro; Kasugai, Yoshimi; Oi, Motoki; Sakai, Kenji; Teshigawara, Makoto; Hasegawa, Shoichi; et al.
Proceedings of 18th Meeting of the International Collaboration on Advanced Neutron Sources (ICANS-18) (CD-ROM), p.118 - 126, 2007/00
One of 23 neutron beam lines of JSNS, NOBORU, has been assigned to the Neutron Facility Group of JAEA. The primary mission of NOBORU is to investigate neutronic performance of JSNS while it can accommodate various trial research experiments. This paper describes an experimental program by using NOBORU mostly in an on-beam commissioning period of JSNS after the first proton beam acceptance in 2008. Topics for the primary mission to be studied are as follows; relationships between operating parameters of JSNS and neutronic performance, acquisition of beam parameters for users, confirmation of integrity in main components of JSNS, validation of neutronic designs, and research and development on measuring techniques. In addition, we are interested in radiography, introduction of a high-pressure instrument and eV neutron spectroscopy, and also welcome trial uses to bring out new research activities.
Harada, Masahide; Maekawa, Fujio; Teshigawara, Makoto; Watanabe, Noboru*; Kato, Takashi; Ikeda, Yujiro
Proceedings of 18th Meeting of the International Collaboration on Advanced Neutron Sources (ICANS-18) (CD-ROM), p.616 - 626, 2007/00
no abstracts in English
Oikawa, Kenichi; Takada, Hiroshi; Maekawa, Fujio; Harada, Masahide; Kato, Takashi; Ikeda, Yujiro
Proceedings of 18th Meeting of the International Collaboration on Advanced Neutron Sources (ICANS-18) (CD-ROM), p.591 - 597, 2007/00
The neutron beam shutter system of JSNS target station in the Materials and Life Science Experimental Facility (MLF) is now in the final stage of the construction. The JSNS shutter system consists of following components; (1) shutter base plates, (2) interstitial blocks, (3) shutter gates, (4) upper shielding blocks, (5) drive assemblies, (6) control systems, and (7) maintenance tools. This shutter system has 23 independent shutter gates and drive systems for each beam port, and its dimensions and materials have been designed to shield/provide the neutron beam of maximum size; 100 mm 
100 mm. The detailed construction steps of our shutter system, especially in its alignment, will be presented in the session.
Takahashi, Nobuaki; Shibata, Kaoru; Sato, Taku*; Nakajima, Kenji; Kajimoto, Ryoichi; Oikawa, Kenichi; Arai, Masatoshi; Schanzer, C.*
Proceedings of 18th Meeting of the International Collaboration on Advanced Neutron Sources (ICANS-18) (CD-ROM), p.373 - 381, 2007/00
A time-of-flight near-backscattering neutron inelastic spectrometer, DIANA has been proposed for the Materials and Life science experimental Facility (MLF) at Japan Proton Accelerator Research Complex (J-PARC). It has been designed to achieve a high neutron flux at a range of low energies, whose wavelength band is between about 1.4 
and 6.4 . We have recently decided to attach the instrument to the coupled moderator source beam-line instead of the decoupled source beam-line, in order to achieve highest intensity at the desired wavelength band. On the other hand, a novel focusing analyzer has been theoretically developed and also designed for the instrument. As a result of this work, it is found that a large beam divergence at the sample is acceptable. Therefore, we have reconsidered the guide system in order to maximize the intensity, according to the report about advanced geometries for neutron guides.
Maruyama, Ryuji; Yamazaki, Dai; Ebisawa, Toru*; Hino, Masahiro*; Soyama, Kazuhiko
Proceedings of 18th Meeting of the International Collaboration on Advanced Neutron Sources (ICANS-18) (CD-ROM), p.197 - 200, 2007/00
The development of high performance neutron supermirrors with high reflectivity and large 
, the ratio of the effective critical angle of the supermirror to that of natural nickel, is important for the J-PARC project since it greatly increases the available neutron intensity. Neutron supermirrors consist of alternating layers of two materials with different refractive indices for neutrons. An ion beam sputtering instrument with an effective deposition area of 0.2 m
has been installed at the Japan Atomic Energy Agency in order to produce neutron guides, benders, and other neutron optical devices, which are planned for application in the J-PARC project. We have succeeded in fabricating the supermirror with large critical angle of 
and that with high reflectivity (
85%) for 
.
Haga, Katsuhiro; Kogawa, Hiroyuki; Wakui, Takashi; Okamoto, Yoshihisa; Futakawa, Masatoshi; Kaminaga, Masanori; Kato, Takashi
Proceedings of 18th Meeting of the International Collaboration on Advanced Neutron Sources (ICANS-18) (CD-ROM), 14 Pages, 2007/00
The construction of the 1MW class mercury target which is the world highest level as the spallation neutron source is going on under the J-PARC project. The mercury target system consists of the mercury target vessel, the mercury circulation system and the target trolley. The outline of the mercury target system and several topics appeared in the course of the system fabrication and assembling are reported. For the target vessel, the residual stress at the beam window was evaluated and it was confirmed that the stress level is low and no problem. For the mercury pump, the mechanical EM pump which is free of mercury leak was developed and we could get prospect that the pump can be used under the beam condition of up to 400kW. For the target trolley, we confirmed that the very heavy body which is nearly 300t can be positioned with the accuracy of 
1mm which is required for the system operation.