Oikawa, Kenichi; Maekawa, Fujio; Tamura, Masaya; Harada, Masahide; Kato, Takashi; Ikeda, Yujiro; Niita, Koji*
LA-UR-06-3904, Vol.2, p.139 - 145, 2006/06
A preliminary investigation on a satellite building for a long-beamline instrument of MLF is now in progress. In order to estimate the total cost of the building, we started the shielding analysis of the beamline using MCNPX and PHITS, where the latest beamline design and the neutron spectrum have been adopted.
Asano, Yoshihiro; Kawashima, Yoshitaka*
Radiation Protection Dosimetry, 115(1-4), p.176 - 180, 2005/12
no abstracts in English
Maekawa, Fujio; Meigo, Shinichiro; Kasugai, Yoshimi; Takada, Hiroshi; Ino, Takashi*; Sato, Setsuo*; Jerde, E.*; Glasgow, D.*; Niita, Koji*; Nakashima, Hiroshi; et al.
Nuclear Science and Engineering, 150(1), p.99 - 108, 2005/05
A neutronic benchmark experiment on a simulated spallation neutron target assembly with 1.94, 12 and 24 GeV proton beams conducted by using the AGS accelerator at BNL/US was analyzed to investigate validity of neutronics calculations on proton accelerator driven spallation neutron sources. Monte Carlo particle transport calculation codes NMTC/JAM, MCNPX and MCNP-4A with associated cross section data in JENDL and LA-150 were used for the analysis. As a result, although the overall energy range was encompassed from GeV to meV, i.e., more than 12 orders of magnitude, calculated fast and thermal neutron fluxes agreed approximately within 40 % with the experiments. Accordingly, it was concluded that neutronics calculations with these codes and cross section data were adequate for estimating nuclear properties in spallation neutron sources.
Tamura, Masaya; Maekawa, Fujio; Harada, Masahide; Haga, Katsuhiro; Konno, Chikara
JAERI-Tech 2005-020, 58 Pages, 2005/03
no abstracts in English
Monte Karuro Keisanho Kodoka No Genjo; Dai-3-Kai Monte Karuro Shimyureshon Kenkyukai Hobunshu, p.233 - 244, 2004/12
Whole evaluation and closing talk at the third Monte Carlo simulation symposium held on June 7-8(2004) are described.
Shiroya, Seiji*; Misawa, Tsuyoshi*; Unesaki, Hironobu*; Ichihara, Chihiro*; Kobayashi, Keiji*; Nakamura, Hiroshi*; Shin, Kazuo*; Imanishi, Nobutsugu*; Kanazawa, Satoshi*; Mori, Takamasa
JAERI-Tech 2004-025, 93 Pages, 2004/03
In view of the future plan of Research Reactor Institute, Kyoto University, the present study consisted of (1) the transmission experiments of high energy neutrons through materials, (2) experimental simulation of ADSR using the Kyoto University Critical Assembly(KUCA), and (3) conceptual neutronics design study on KUR type ADSR using the MCNP-X code. Through the present study, valuable knowledge on the basic nuclear characteristics of ADSR, which is indispensable to promote the study on ADSR, was obtained both theoretically and experimentally. For the realization of ADSR, it is considered to be necessary to accumulate results of research steadily. For this purpose, it is inevitable (1) to compile the more precise nuclear data for the wide energy range, (2) to establish experimental techniques for reactor physics study on ADSR including subcriticality measurement and absolute neutron flux measurement, and (3) to develop neutronics calculation tools which take into account the neutron generation process by the spallation reaction and the delayed neutron behavior.
Sasa, Toshinobu; Oigawa, Hiroyuki; Tayama, Ryuichi*; Hayashi, Katsumi*
Journal of Nuclear Science and Technology, 41(Suppl.4), p.30 - 33, 2004/03
The construction of Transmutation Experimental Facility (TEF) is planned under the framework of Japan Proton Accelerator Research Complex (J-PARC) project. A liquid lead-bismuth (Pb-Bi) spallation target with beam power of 600MeV-200kW will be installed into the TEF. Analyses were performed to determine the effective thickness of biological shield for Pb-Bi target by using both MCNPX and ATRAS code system. Thickness of around 6m should be required to decrease the radiation level. The streaming analyses through the proton injection beam duct and the primary cooling circuit piping were also performed. The result of the beam duct streaming shows good agreement between the results of MCNPX and DUCT-III. The additional shield must be installed to suppress the activation of accelerator components. In the case of streaming through the primary cooling circuit piping, it is proved that the radiation level at the exit of the shield is allowable. The radiation level can be much more reduced by optimizing the bending position and length of the piping.
Nakano, Hideo*; Masukawa, Fumihiro; Nakashima, Hiroshi; Sasamoto, Nobuo*; Tayama, Ryuichi*; Handa, Hiroyuki*; Hayashi, Katsumi*
Journal of Nuclear Science and Technology, 41(Suppl.4), p.50 - 53, 2004/03
In order to estimate accuracy of the various calculation methods for the neutron streaming through a maze and duct in proton accelerator facilities, we performed benchmark analyses by using the radiation shielding design codes. According to the results of the benchmark analyses, it is concluded that NMTC/MCNP, MCNPX and DUCT-III are applicable to actual calculation of the duct-streaming radiations for J-PARC.
Akiyama, Mitsunaga*; Katakura, Fumishige*; Kawasaki, Nobuo*; Nemoto, Toshiyuki*; Tsuruoka, Takuya*; Adachi, Masaaki*; Ishizuki, Shigeru*; Kume, Etsuo
JAERI-Data/Code 2003-009, 307 Pages, 2003/07
Several computer codes in the nuclear field have been vectorized, parallelized and transported on the supar computer system at Center for Promotion of Computational Science and Engineering in Japan Atomic Energy Research Institute. We dealt with 10 codes in fiscal 2001. In this report, the parallelization of Newtron Radiography for 3 dimensional CT code NR3DCT, the vectorization of Unsteady-state heat conduction code THERMO3D, the porting of initial program of MHD simulation, the tuning of Heat And Mass Balance Analysis Code HAMBAC, the porting and parallelization of Monte Carlo N-Particle transport code MCNP4C3, the porting and parallelization of Monte Carlo N-Particle Transport code system MCNPX2.1.5, the porting of code CINAC-V4, the porting of Assisted Model Building with Energy Refinement Amber5 code system, the part of additional VisLink library Multidimensional Two-fluid model code ACD3D and the porting of experiment data processing code for GS8500 to SR8000 are described.
Maekawa, Fujio; Tamura, Masaya
Proceedings of ICANS-XVI, Volume 3, p.1051 - 1058, 2003/07
A three-dimensional (3-D) shielding calculation model for MCNPX was produced for shielding design of 1-MW JSNS. The model included simplified target-moderator-reflector assembly, helium-vessel and neutron beam extraction pipes, shutters, shield blocks, gaps and void spaces between these components, and so on, and could treat streaming effects precisely. The particle splitting and kill method with cell importance parameters was adopted as a variance reduction method. The cell importance parameters for such a large target station of about 15 m in diameter and 12 m in hight in which neutron fluxes attenuated more than 12 orders of magnitude could be determined appropriately by automated iteration calculations. This calculation procedure enabled detailed 3-D shielding design calculations for the whole target station in a short time, i.e., within 2 days, and contributed for progress of shielding designs of JSNS.
Meigo, Shinichiro; Harada, Masahide; Takada, Hiroshi
Proceedings of ICANS-XVI, Volume 3, p.1059 - 1067, 2003/07
In the neutronics design for the J-PARC facilities, transport codes of NMTC/JAM, MCNPX and MARS are used. In order to confirm the predict ability for these codes, it is important to compare with the experiment result. For the validation of the source term of neutron, the calculations are compared with the experimental spectrum of neutrons produced from thick target. Although slightly disagreement exists, NMTC/JAM, MCNPX and MARS are in good agreement with the experiment within by a factor of 2.
Tamura, Masaya; Maekawa, Fujio
JAERI-Tech 2003-010, 54 Pages, 2003/03
Evaluation of shielding performance for a spallation neutron source facility in the J-PARC Project is important from a viewpoint of radiation safety and optimization of arrangement of components. This report describes evaluated results for the shielding performance with modeling three-dimensionally whole structural components including gaps between them in detail. A Monte Carlo calculation method with MCNPX2.2.6 code and LA-150 library was adopted. Streaming and void effects, optimization of shield for cost reduction and optimization of arrangement of structures such as shutters were investigated. Horizontal required shield thicknesses were ranged from about 6.5m to 7.5m as a function of neutron beam line angles. A shutter mechanism for a horizontal neutron reflectometer that was directed downward was devised, and it was shown that the shielding performance of the shutter was acceptable. An optimal biological shield configuration was finally determined according to the calculated results.
Endo, Akira; Yamaguchi, Yasuhiro; Takahashi, Fumiaki
Radiation Risk Assessment Workshop Proceedings, p.151 - 156, 2003/00
We have developed a new system using numerical simulation technique for analyzing dose distribution in various postures by neutron, photon and electron exposures. The system consists of mathematical human phantoms with movable arms and legs and Monte Carlo codes MCNP and MCNPX. This system was applied to the analysis of dose distribution for the heavily exposed workers in the Tokai-mura criticality accident. The paper describes the simulation technique employed and a summary of the dose analysis.
Konno, Chikara; Ikeda, Yujiro
Journal of Nuclear Science and Technology, 39(Suppl.2), p.1041 - 1044, 2002/08
no abstracts in English
Maekawa, Fujio; Niita, Koji*; Meigo, Shinichiro; Kasugai, Yoshimi; Ikeda, Yujiro; Takada, Hiroshi; Ino, Takashi*; Sato, Setsuo*; ASTE Collaboration Team
JAERI-Conf 2001-002, p.983 - 991, 2001/03
no abstracts in English