Off-gas processing system operations for mercury target vessel replacement at J-PARC

Kai, Tetsuya; Uchida, Toshitsugu; Kinoshita, Hidetaka; Seki, Masakazu; Oi, Motoki; Wakui, Takashi; Haga, Katsuhiro; Kasugai, Yoshimi; Takada, Hiroshi

Journal of Physics; Conference Series, 1021(1), p.012042_1 - 012042_4, 2018/06

https://doi.org/10.1088/1742-6596/1021/1/012042

Recovery of helium refrigerator performance for cryogenic hydrogen system at J-PARC MLF

Aso, Tomokazu; Teshigawara, Makoto; Hasegawa, Shoichi; Muto, Hideki; Aoyagi, Katsuhiro; Nomura, Kazutaka; Takada, Hiroshi

Journal of Physics; Conference Series, 1021(1), p.012085_1 - 012085_4, 2018/06

BB2016-1899.pdf:0.54MB

https://doi.org/10.1088/1742-6596/1021/1/012085

Measurement of activation cross sections of the target and the proton beam window materials at J-PARC

Matsuda, Hiroki; Meigo, Shinichiro; Iwamoto, Hiroki

Journal of Physics; Conference Series, 1021(1), p.012016_1 - 012016_4, 2018/06

https://doi.org/10.1088/1742-6596/1021/1/012016

For the improvement of the accuracy of nuclear design for spallation neutron sources and transmutation systems, nuclear reaction cross sections are required. Considering decommissioning of the accelerator facilities, accurate cross sections are mandatory. The activation cross sections have been measured in several facilities. However, they have low accuracy and precision. Especially, since there is almost no data for 3 GeV protons which are used for spallation neutron source (JSNS) in J-PARC, the experimental data is required for the improvement of the target materials.For the sake of the forthcoming full-time measurement of the activation cross sections for various nuclei, we measured the ones of aluminium with 0.4, 1.3, 2.2, and 3.0 GeV protons as the test purpose. It was found that more accurate data than current ones would be measured by using precise beam controls and highly accurate beam monitoring. We compared the experimental data, the evaluated data (JENDL-HE/2007), and the calculations with several intra-nuclear cascade models by PHITS code. Although the experimental data agreed with JENDL-HE/2007, the calculations underestimated about 40%. This could come from the evaporation model (GEM) being included in PHITS code. We found that the calculations agreed with the experimental data by upgrading PHITS code.

Present fabrication status of spare moderators and reflector in J-PARC spallation neutron source

Teshigawara, Makoto; Harada, Masahide; Oi, Motoki; Takada, Hiroshi

Journal of Physics; Conference Series, 1021(1), p.012061_1 - 012061_4, 2018/06

https://doi.org/10.1088/1742-6596/1021/1/012061

At the spallation neutron source of J-PARC, the structural material of moderators and reflector, such as an aluminum alloy, is going to reach to the design value (20 DPA) around 2020 by an accumulation of irradiation-damage. We started the fabrication of the spare moderators and reflector in 2013 with following design of two improvements. The invar joints, such as invar-A6061 and invar- SS316L joints were newly developed to utilize them in the cryogenic multi-layered pipe with 5th annular geometry, improving the fabrication procedure much simple. The Gold-Indium-Cadmium (Au-In-Cd) as a decoupler material is also developed to reduce residual radioactivity of the used components significantly for the decoupled moderator. In this presentation, we will report these results and progress of fabrication.

Shielding analysis of Transmutation Experimental Facility

Iwamoto, Hiroki; Matsuda, Hiroki; Meigo, Shinichiro

Journal of Physics; Conference Series, 1021(1), p.012049_1 - 012049_4, 2018/06

https://doi.org/10.1088/1742-6596/1021/1/012049

To promote research, development, and demonstration of elemental technologies for accelerator-driven systems (ADS), the Japan Atomic Energy Agency (JAEA) is planning to construct Transmutation Experimental Facility (TEF) at J-PARC. At ADS Target Test Facility (TEF-T), 250-kW H beams accelerated by the 400-MeVLINAC will be derived to a lead-bismuth eutectic (LBE) target for the material examinations aimed for the ADS. The TEF-T will operate as a spallation neutron source especially for research and development of semiconductor by using high-energy neutrons. For the license of this facility, the shielding design is important because unnecessary shield increase drastically the cost of construction. In this study, shielding analysis was carried out for whole structure of the TEF in detail toward the construction. To reduce the neutron flux and cost efficiently, an iron and an ordinary concrete will be employed as shield. The detailed structure for the shielding was determined by the PHITS code based on the intra-nuclear cascade with statistical decay model. It was found that the backward neutrons from the target are important to reduce the cost of the shielding so that we have plan to measure by using J-PARC accelerator. Shielding including the beam tunnel, hot-cell to maintain the LBE target, beam dumps for beam commissioning, and a neutron beam port for multipurpose utilization were also determined. This paper presents the results of the shielding analysis for these components and the shielding structure of the whole TEF.

On-beam commissioning of the energy resolved neutron imaging system, RADEN, of J-PARC

Kai, Tetsuya; Shinohara, Takenao; Hiroi, Kosuke; Su, Y. H.; Oikawa, Kenichi; Segawa, Mariko; Nakatani, Takeshi; Hayashida, Hirotoshi*; Parker, J. D.*; Matsumoto, Yoshihiro*; et al.

no journal, ,