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Nagai, Takayuki; Okamoto, Yoshihiro; Akiyama, Daisuke*; Sato, Nobuaki*
no journal, ,
no abstracts in English
Masuda, Shiho; Kai, Tetsuya; Harada, Masahide; Kinoshita, Hidetaka; Seki, Masakazu; Takagi, Motonori; Kasugai, Yoshimi; Haga, Katsuhiro
no journal, ,
Mercury is used as a target material for spallation neutron source at J-PARC. It is assumed that most of gaseous nuclides (tritium, noble gases and mercury vapor) among spallation products accumulate in the cover gas (helium) of the surge tank in the Mercury Circulation System (MCS). In the mercury target vessel replacement which is carried out every year, cover gas is transferred to the off-gas processing system before deinstallation of the vessel. It became clear from the previous operation that a certain amount of tritium and noble gases remain absorbed on the inner wall of the MCS. It is necessary to suppress release of these nuclides to the hot cell during vessel replacement. Therefore, the MCS was purged by helium several times to reduce the radioactivity concentration in the system. As a result, the purge was effective for the reduction of noble gas, but not for tritium. Therefore, at the time of replacement, air is drawn into the off-gas processing system via the MCS using a vacuum pump, thereby forming a air flow toward the inside (air-flow control) of the MCS at the opening to suppress the release of tritium out of the system. In this report, we will introduce the role of the off-gas processing system in mercury target vessel replacement and describe the efficacy to suppress the noble gas and tritium release, and future plan of system improvement.
Harada, Masahide; Kawakami, Kazuhiro*; Aizawa, Kazuya; Soyama, Kazuhiko; Ishikado, Motoyuki*; Hiramatsu, Hideyuki*; Hashimoto, Norimichi*; Hosoya, Tomonori*; Ichimura, Katsuhiro*
no journal, ,
no abstracts in English
Takeda, Masayasu; Murayama, Yoji
no journal, ,
no abstracts in English
Nakatani, Takeshi; Inamura, Yasuhiro; Ito, Takayoshi*; Okazaki, Nobuo*; Moriyama, Kentaro*; Kasai, Satoshi*; Seya, Tomohiro*; Yasu, Yoshiji*; Oshita, Hidetoshi*; Otomo, Toshiya*
no journal, ,
no abstracts in English
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under ultrasound irradiationShamoto, Shinichi; Matsuura, Masato*; Akatsu, Mitsuhiro*; Yasui, Yukio*; Ito, Takashi; Ieda, Junichi; Endo, Hitoshi*; Oda, Tatsuro*; Chang, L.-J.*; Nemoto, Yuichi*; et al.
no journal, ,
no abstracts in English
Sakai, Kenji; Oku, Takayuki; Okudaira, Takuya; Kai, Tetsuya; Harada, Masahide; Hiroi, Kosuke; Hayashida, Hirotoshi*; Shimizu, Hirohiko*; Yamamoto, Tomoki*; Ino, Takashi*; et al.
no journal, ,
In neutron fundamental physics, a study of correlation term 
of a neutron spin s and a target nuclear spin 
is important because the term interferes to parity non-conserving (PNC) and time reversal non-conserving (TRNC) terms. For this study, a xenon (Xe) is an interesting nucleus because it has been observed an enhancement of PNC effect around neutron resonance peaks, and polarizes up to 
by using a spin exchange optical pumping (SEOP) method. We attempted to develop a polarized Xe target in a compact 
SEOP system and measure neutron polarizing ability caused by the term at a 9.6 eV 
-wave resonance peak of 
Xe, by detecting change 
of a ratio between neutron transmissions with the polarized and unpolarized Xe target. As preliminary results, we observed a signified value of 
after demonstrating that our apparatus could distinguish Doppler broadening effect as systematic error.
He neutron spin filter at JAEAOkudaira, Takuya; Oku, Takayuki; Sakai, Kenji; Ino, Takashi*; Hayashida, Hirotoshi*; Hiroi, Kosuke; Shinohara, Takenao; Kakurai, Kazuhisa*; Aizawa, Kazuya
no journal, ,
The technology development section carries out the development of the neutron polarization device: He Spin Filter. 
He spin filter is a neutron polarization device composed of polarized He gas and alkali metal encapsulated into a special glass cell. Since a neutron absorption cross section of He has very large spin dependence, a polarized neutron beam can be obtained passing through the polarized He gas. He nuclei are polarized irradiating a circularly polarized laser (Spin Exchange Optical Pumping method). The development of the He spin filter is ongoing in JAEA. A system for the electron paramagnetic resonance, which can measure the He polarization without the neutron beam, was developed. Additionally, a vacuum system to make He spin filter was constructed and the development of high quality He spin filter using Rb and K (Hybrid SEOP) is also ongoing. The current status of the development at JAEA will be presented.
Kai, Tetsuya; Su, Y. H.; Hiroi, Kosuke; Shinohara, Takenao; Oikawa, Kenichi; Hayashida, Hirotoshi*; Parker, J. D.*; Matsumoto, Yoshihiro*; Segawa, Mariko; Nakatani, Takeshi; et al.
no journal, ,
no abstracts in English
Inamura, Yasuhiro; Ito, Takayoshi*; Oshita, Hidetoshi*; Yasu, Yoshiji*
no journal, ,
Utsusemi is the software to analyze and visualize data measured by the neutron scattering experiments at MLF in J-PARC. Utsusemi developments, however, started about ten years ago, and old and obsolete script language, python2, is used for its coding. Therefore, we attempt to refactor the old codes to be executed on latest environment, Python 3. In addition, we decided to separate some parts of visualization software from Utsusemi to append the other series of common visualization software, called uGao. As the result, the structure of Utsusemi becomes simple and easy to use for users and developers more. In this presentation, we show the new topics about our recent works on Utsusemi software.
Kajimoto, Ryoichi; Nakamura, Mitsutaka; Kamazawa, Kazuya*; Inamura, Yasuhiro; Ikeuchi, Kazuhiko*; Iida, Kazuki*; Ishikado, Motoyuki*; Murai, Naoki
no journal, ,
no abstracts in English