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Hoshino, Tsuyoshi; Terai, Takayuki*
no journal, ,
no abstracts in English
Nakase, Masahiko*; Chiba, Go; Saito, Masaki*
no journal, ,
Higher-order eigenvalues can be useful indices for reactor core stability. Usually, higher-order eiganvalues are calculated with the subtraction method in which several numerical techniques are necessary. In this present study, we develop a simple method to estimate higher-order eigenvalues from a residual of power iteration. Through numerical calculations with the IAEA benchmark problem, the present method estimates higher-order eigenvalues up to the 5th order quite well.
Chiba, Satoshi; Iwamoto, Osamu
no journal, ,
Difference in the spin-parity distributions of surrogate and neutron-induced reactions is investigated. It was found that the surrogate ratio method would work if (1) the weak Weisskopf-Ewing condition, defined in this work, is satisfied, (2) the spin-parity distributions in the 2 surrogate reactions are equivalent, and (3) the difference of the average spin values in the surrogate and neutron-induced reactions is not much larger than 10 
.
Chikazawa, Yoshitaka
no journal, ,
no abstracts in English
Hashimoto, Shintaro; Chiba, Satoshi; Aritomo, Yoshihiro; Utsuno, Yutaka
no journal, ,
The spin-parity distribution of the residual nucleus produced by the surrogate reaction is an important quantity to derive reliable measurements of the neutron induced reaction cross section indirectly. In this meeting, we will show the distribution formed by the two-nucleon transfer reaction, and discuss the difference from that by the neutron induced reaction.
Mukai, Masayuki; Shimada, Taro; Tanaka, Tadao; Sukegawa, Takenori; Nakayama, Shinichi
no journal, ,
A code for evaluation of exposed doses for public and workers by decommissioning of nuclear cycle facilities was developed based on DecDose code which was developed by JAEA and intended to assess safety of decommissioning for atomic power reactors. We discussed on characteristic aspects particular to the nuclear cycle facilities and improved DecDose on the subject of operation process, target nuclides, and exposure pathways. Evaluation result by the developed code applied on a trial basis to uranium-enrichment factory was reasonably reflected the particular aspects of the nuclear cycle facilities in exposure doses.
Tatekawa, Takayuki; Nakajima, Kohei*; Kim, G.; Teshima, Naoya; Suzuki, Yoshio; Takemiya, Hiroshi
no journal, ,
no abstracts in English
Utsuno, Yutaka; Chiba, Satoshi
no journal, ,
no abstracts in English
Koura, Hiroyuki
no journal, ,
no abstracts in English
Aritomo, Yoshihiro; Chiba, Satoshi; Hashimoto, Shintaro; Utsuno, Yutaka; Koura, Hiroyuki
no journal, ,
no abstracts in English
Li+n inelastic reactions in the Continuum Discredited Coupled Channels (CDCC) methodIchinkhorloo, D.*; Matsumoto, Takuma*; Hirabayashi, Yoshiharu*; Kato, Kiyoshi*; Chiba, Satoshi
no journal, ,
The few-body, especially three-body, problem is still an open (and therefore interesting) subject in nuclear physics, and has been studied intensively by various theoretical frameworks. The n + Li reactions are important not only from the basic interest but also from the application point of view. The Li nucleus is well described by the cluster model such as 
+ d and + p + n. Therefore, it is necessary for us to treat the n + Li system with + p + n and + p + n + n models. In this work, we study the Li+n inelastic reactions applying the + d cluster model to Li and using the continuum-discredited coupled-channels (CDCC) approach.
Ebine, Masumi; Katagiri, Masaki*; Nakamura, Tatsuya; Birumachi, Atsushi; Hosoya, Takaaki*
no journal, ,
no abstracts in English
Shimada, Taro; Takamura, Atsushi*; Kamiya, Atsushi*; Sukegawa, Takenori; Tanaka, Tadao
no journal, ,
Dispersion ratios, size distribution of particles and filtration efficiencies were measured when piping for reactor cooling system at Fugen reactor was segmented in the contamination control enclosure. Dispersion ratio of Co-60 was observed to be 18 to 23% for normal piping and that to be 34 to 43% for vertically segmented piping, which was half of the normal. Filtration efficiency of pre-filter was observed to be 55 to 80%, while particles smaller than 1micrometer were not able to be collected. It was confirmed that the filtration efficiency of HEPA filter was more than 99.9% for Co-60.
Amamoto, Ippei; Kofuji, Hirohide; Tsuzuki, Tatsuya*; Mitamura, Naoki*; Takasaki, Yasushi*; Shibayama, Atsushi*; Yano, Tetsuji*; Terai, Takayuki*
no journal, ,
no abstracts in English
Tamura, Itaru; Arai, Masaji; Komeda, Masao; Sagawa, Hisashi
no journal, ,
no abstracts in English
Kawase, Keigo; Shimomura, Takuya; Kando, Masaki; Yoshida, Hidetsugu*; Bulanov, S. V.
no journal, ,
In the development of the Compton backscattered X-ray source by using the Microtron accelerator and the Nd:YAG laser, we are constructing the laser pulse compression system via stimulated Brillouin scattering for increasing the flux of the X-ray beam. In this annual meeting, we report the present status of the development of the pulse-compression system.
Hirose, Takanori; Tanigawa, Hiroyasu; Enoeda, Mikio
no journal, ,
no abstracts in English
Nakagawa, Akinori; Sone, Tomoyuki; Sasaki, Toshiki; Nakazawa, Osamu; Tashiro, Kiyoshi
no journal, ,
no abstracts in English
Yanagisawa, Kazuaki
no journal, ,
By using a mini-plate fuel (density 4.8g/cc) fabricated as a simulation of JMTR silicide fuel plate, an in-core irradiation test postulating a reactivity insertion by cold coolant induction was performed. The test is known as an abnormal transient phenomenon to be caused during JMTR operation. Taking into account that the peak cladding surface temperature predicted by EURECA computer code for JMTR safety evaluation is 53 
C in maximum, more severe condition is imposed on in-core tested mini-plate fuel, where a peak cladding surface temperature is as high as 111 C. It is revealed from post-irradiation examination that the tested mini-plate fuel was intact. From this experimental fact, it is found that JMTR silicide fuel plate has a safety margin against a reactivity insertion by cold coolant induction.
Kinoshita, Hidetaka; Kogawa, Hiroyuki; Haga, Katsuhiro; Naoe, Takashi; Ida, Masato; Futakawa, Masatoshi
no journal, ,
Mercury is used for the spallation neutron source target of the J-PARC Materials and Life Science Experimental Facility (MLF). Pressure is generated by pulsed proton beam because of high heat generation within very short time. Cavitation erosion is occurred at target vessel inner surface by pressure wave. This phenomenon will be shortening the life time of the target vessel. Pressure wave mitigation by microbubble injection will be effective to solve this issue. The bubble size and void fraction are confirmed by numerical analysis for pressure wave mitigation. But the information of effective microbubble injection system and microbubble motion in flowing fluid is not sufficient. Then R&D of microbubble injection system and bubble observation were conducted experimentally. In this report, introduction of the mockup test apparatus simulated actual target and test results of pressure drop at microbubble injection system are presented.