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Kaburagi, Masaaki; Shimazoe, Kenji*; Terasaka, Yuta; Tomita, Hideki*; Yoshihashi, Sachiko*; Yamazaki, Atsushi*; Uritani, Akira*; Takahashi, Hiroyuki*
Nuclear Instruments and Methods in Physics Research A, 1046, p.167636_1 - 167636_8, 2023/01
We focus on the thickness and property controls of inorganic scintillators used for thermal neutron detection in intense -ray fields without considering pulse shape discrimination techniques. GS20 (a lithium glass) and LiCaAlF:Ce(LiCAF:Ce) cintillators with thicknesses of 0.5 and 1.0 mm, respectively, have been employed. Pulse signals generated by photomultiplier tubes, to which the scintillators were coupled, were inserted into a digital pulse processing unit with 1 Gsps, and the areas of waveforms were integrated for 360 ns. In a Co -ray field, the neutron detection for GS20 with a 0.5-mm thickness was possible at dose rates of up to 0.919 Gy/h; however, for LiCAF:Ce, neutron detection was possible at 0.473 Gy/h, and it failed at 0.709 Gy/h. Threfore, in a Co -ray field, the neutron/-ray discrimination of GS20 was better than that of LiCAF:Ce due to its better energy resolution and higher detection efficiency.
Magome, Hirokatsu; Okada, Yuji; Tomita, Kenji; Iida, Kazuhiro; Ando, Hitoshi; Yonekawa, Akihisa; Ueda, Haruyasu; Hanawa, Hiroshi; Kanno, Masaru; Sakuta, Yoshiyuki
JAEA-Technology 2015-025, 100 Pages, 2015/09
In Japan Atomic Energy Agency, in order to solve the problem in the long-term operation of a light water reactor, preparation which does the irradiation experiment of light-water reactor fuel and material was advanced. JMTR stopped after the 165th operation cycle in August 2006, and is advancing renewal of the irradiation facility towards re-operation. The material irradiation test facility was installed from 2008 fiscal year to 2012 fiscal year in JMTR. The material irradiation test facility is used for IASCC study, and that consists of mainly three equipments. This report is described performance operating test of the water environmental control facilities for IASCC study carried out 2013 fiscal year.
Takita, Kenji; Iimura, Koichi; Tomita, Kenji; Endo, Yasuichi; Kanno, Masaru
JAEA-Technology 2012-006, 41 Pages, 2012/03
At JAEA Oarai Research and Developnment Establishment (JAEA Oarai), JAEA Oarai was proceeding a plan to repair JMTR, which is to re-operate in fiscal 2012. Additionally, as an effective utilizati of JMTR, JAEA Oarai is planning to manufacture Mo, which is a parent nuclide of Tc. Tc is most commonly used as a radiopharmaceution in the field of nuclear medicine. Currently Mo supply is dependent only on foreign imports, so JAEA is aiming for working on partially manufacturing Mo domestically with industrial circles in Japan. In this article, this report described the choice and fabric of irradiathion facility named Hydraulic Rabbit Facility for manufacturing Mo, the technical study of fabrication technique.
Takita, Kenji; Iimura, Koichi; Tomita, Kenji; Endo, Yasuichi; Kanno, Masaru
UTNL-R-0480, p.7_4_1 - 7_4_6, 2012/03
no abstracts in English
Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Armendariz, R.*; et al.
Physical Review C, 83(6), p.064903_1 - 064903_29, 2011/06
Times Cited Count:176 Percentile:99.41(Physics, Nuclear)Transverse momentum distributions and yields for , and in collisions at = 200 and 62.4 GeV at midrapidity are measured by the PHENIX experiment at the RHIC. We present the inverse slope parameter, mean transverse momentum, and yield per unit rapidity at each energy, and compare them to other measurements at different collisions. We also present the scaling properties such as and scaling and discuss the mechanism of the particle production in collisions. The measured spectra are compared to next-to-leading order perturbative QCD calculations.
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
Times Cited Count:7 Percentile:49.81(Physics, Nuclear)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.
Owada, Kenji; Tomita, Yusuke*
Nihon Butsuri Gakkai-Shi, 65(10), p.800 - 804, 2010/10
no abstracts in English
Hosokawa, Jinsaku; Iimura, Koichi; Ogawa, Mitsuhiro; Tomita, Kenji; Yamaura, Takayuki
JAEA-Technology 2010-018, 269 Pages, 2010/08
At Oarai Research and Development Center, Japan Atomic Energy Agency (JAEA) advances the plan of refurbishing Japan Materials Testing Reactor (JMTR) to start the operation in fiscal 2011. Fuel Transient Test Facility is scheduled to be set up as neutron irradiation test equipment of the light-water reactor fuel that uses JMTR after it operates again. The abnormal transition examination device is the irradiation facilities where the output sudden rise examination that makes the light-water reactor fuel an irradiation sample is done to use it to develop the safety evaluation technology and the damage influence evaluation technology of the light-water reactor fuel that reaches high burn-up. In this report, as for the system design, it is a summary to JMTR among detailed designs of the abnormal transition examination device of the installation schedule.
Owada, Kenji; Tomita, Yusuke*
Journal of the Physical Society of Japan, 79(1), p.011012_1 - 011012_10, 2010/01
Times Cited Count:23 Percentile:74.49(Physics, Multidisciplinary)Onuma, Yuichi; Tomita, Kenji; Okada, Yuji; Hanawa, Hiroshi
JAEA-Technology 2009-034, 79 Pages, 2009/07
Toward the re-operation of Japan Materials Testing Reactor on 2011 F.Y., the construction of new material irradiation facility for the stress corrosion cracking research under the LWR irradiation environment had been planed, and the design study of water control unit for BWR and water chemical study which supply the LWR simulated water to the material irradiation capsule were carried out on 2007 F.Y. The design study of new material irradiation facility was examined including the reflection of the operation experience and the reuse of components on old material irradiation facility. These examination results were summarized in this report.
Iimura, Koichi; Ogawa, Mitsuhiro; Tomita, Kenji; Tobita, Masahiro
JAEA-Technology 2009-021, 71 Pages, 2009/05
The preparation of a fuel transient test using the JMTR is advanced to conduct its irradiation test from 2011 F.Y. after re-operation of the JMTR. The fuel behavior for high burn-up BWR's under power ramping condition will be evaluated in simulating the BWR environmental condition using the shroud irradiation facility (Oarai Shroud Facility No.1) and He power-control type BOCA (Boiling Water Capsule) irradiation facility, which is composed of the capsule control device, He power-control device and boiling water capsule. In order to change the fuel irradiation conditions so as to treat high burn-up fuels (from 50 GWD/t-UO to 110 GWD/t-U), it is necessary to revaluate the dose for the safety evaluation at the test fuel failure. In this report, evaluations for equivalent dose rate of each device and exposure dose of handling operators when all fission products released in the coolant of the capsule control device and the BOCA at fuel failure in the fuel transient test are summarized.
Ogawa, Mitsuhiro; Iimura, Koichi; Tomita, Kenji; Tobita, Masahiro
JAEA-Technology 2009-017, 254 Pages, 2009/05
In JMTR, upgrade of irradiation facilities is advanced to re-operate from 2011 F.Y. In order to irradiate test fuels of high-burnup, external exposure reassessment by direct and skyshine gamma rays of the nuclear fuel handling facility at JMTR was performed. In evaluation method, radiation source of maximum use of the nuclear fuel was calculated by using ORIGEN2 code. Dose equivalent rate for supervised area boundary was calculated by modeling reactor building at using shielding calculation codes QAD-CGGP2 and G33-GP2. As a result of evaluation, it was confirmed that the effective dose equivalent during year was low enough at supervised area boundary of the JMTR site.
Tomita, Kenji; Inoue, Shuichi; Ishida, Takuya; Onuma, Yuichi; Tsuchiya, Kunihiko
JAEA-Technology 2008-050, 41 Pages, 2008/07
Blanket Functional Facility (BFT) for fusion blanket development was established in the Japan Materials Testing Reactor (JMTR). The irradiation tests with LiTiO pebble-bed were carried out with the BFT. The BFT was constituted a sweep gas device for tritium measurement and recover and a capsule controlled device for temperature control and neutron flux measurement of LiTiO pebble-bed. Five tritium monitors (ion chambers) for tritium measurement were established in the sweep gas device. In these tritium monitors, one tritium monitor for the measurement of tritium release property (TmIRA201) was not able to be used and it is necessary to exchange new tritium monitors. This report is described the fabrication of new tritium monitors and exchange procedure of this monitors.
Tomita, Kenji; Hosokawa, Jinsaku; Matsui, Yoshinori
JAEA-Technology 2008-043, 21 Pages, 2008/07
In JMTR, highly precise-ization of irradiation temperature evaluation of material capsule is advanced towards re-operation in the 2011 fiscal year. In the conventional sub-program, rectangular form was loaded into the capsule and temperature evaluation was carried out. In this development, the CT specimen which is special form is loaded into capsule, and it enabled it to analyze a temperature distribution. Moreover, the sub-program which can also evaluate the heat stress distribution by this uneven temperature distribution was developed. And, in order to be able to perform easily extraction and re-load of irradiation specimens, the structure of separation specimen holder effective in a re-irradiation examination is adopted. However, with this structure, the inside of capsule serves as uneven temperature distribution. For this reason, the sub-program which can evaluate this temperature distribution was developed.
Tomita, Kenji; Tsuchiya, Kunihiko; Onuma, Yuichi; Inoue, Shuichi; Watanabe, Hiroyuki; Saito, Takashi; Kikuchi, Taiji; Hayashi, Kimio; Kitajima, Toshio
JAEA-Technology 2008-036, 61 Pages, 2008/06
The second in-situ irradiation experiment using a mock-up (ORIENT-II, JMTR capsule Number: 99M-54J) with a tritium breeder (LiTiO) pebble bed in the Japan Materials Testing Reactor (JMTR) was finished on Aug. 1, 2006. Consideration on the detaching procedure of the irradiated mock-up contaminated with tritium with pebble bed and a detaching test of this mock-up was carried out. The tritium removal properties were examined in the irradiated mock-up, the sweep gas tube, the protective tube and the junction box, for the decreasing of the tritium release to the area of detaching test. Melting/enclosed tests of sealing plug were also carried out for the prevention of tritium leakage from sweep gas lines of pebble bed. Then, the detaching test of the pebble bed was carried out. This report describes the results of tritium removal tests, examination of the detaching procedure, and the detaching test, as well as knowledge obtained from these tests and works.
Ikeshima, Yoshiaki; Ishida, Takuya*; Tsuchiya, Kunihiko; Tomita, Kenji; Ebisawa, Hiroyuki; Magome, Hirokatsu; Nakamichi, Masaru*; Kitajima, Toshio; Kawamura, Hiroshi
JAERI-Tech 2005-005, 37 Pages, 2005/02
no abstracts in English
Oshima, Jun; Ashida, Takashi; Isozaki, Kazunori; Sumino, Kozo; Yamaguchi, Akira; Sakaba, Hideo; Ozawa, Kenji; Tomita, Naoki
JNC TN9410 2004-011, 279 Pages, 2004/04
The MK-III project to improve the irradiation capability of the experimental fast reactor JOYO have been carried out since 1987.The increase of fast neutron flux and the enlargement of irradiation field increase the reactor thermal power from 100MWt to 140MWt. To accommodate the increased thermal power,the IHXs and the IHX connecting piping were replaced. The IHXs were replaced with securing cooling system boundary in high dose rate surroundings and very limited operation space of the radiation controlled area in the containment vessel. Primary sodium contains radioactive 22Na,24Na and radioactive CPs such as 60Co and 54Mn,and this sodium adhered to the inner surface of IHXs and pipe. Therefore, the renovation procedure and method were carefully examined based on the JOYO operation and maintenance experiences and research and development results on the sodium handling technique.The major results obtained in the primary heat transport mechanical system (IHXs) renovation operation were shown as follows;
Shingu, Kazuki*; Adachi, Kazuhiro*; Horinokuchi, Kenji*; Tomita, Teruo*
JNC TJ7400 2005-006, 358 Pages, 1993/03
The objective of this study is to prove a long-term geoscientific stability of geological environment by means of measuring stress state and rock property around the active fault in order to investigate geological environment influenced by fault movement in underground as well as surface. The study was conducted in Mozumi mine of the Kamioka mining district, located in the Atotsu active faults system zone.
Ogawa, Mitsuhiro; Hosokawa, Jinsaku; Tomita, Kenji; Iimura, Koichi; Sakuta, Yoshiyuki
no journal, ,
no abstracts in English
Yamagishi, Akihiko*; Yokobori, Shinichi*; Hashimoto, Hirofumi*; Yano, Hajime*; Imai, Eiichi*; Okudaira, Kyoko*; Kawai, Hideyuki*; Kobayashi, Kensei*; Tabata, Makoto*; Nakagawa, Kazumichi*; et al.
no journal, ,
no abstracts in English