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Yoshitomi, Hiroshi; Tanimura, Yoshihiko*; Tatebe, Yosuke; Tsutsumi, Masahiro; Kawasaki, Katsuya; Kowatari, Munehiko; Yoshizawa, Michio; Shimizu, Shigeru*; Kim, J.-S.*; Lee, J.-G.*; et al.
Proceedings of 4th Asian and Oceanic Congress on Radiation Protection (AOCRP-4) (CD-ROM), 4 Pages, 2015/07
Am-Be sourceKowatari, Munehiko; Onuma, Isamu; Tanimura, Yoshihiko; Kawasaki, Katsuya; Saegusa, Jun; Yoshizawa, Michio
Radioisotopes, 57(9), p.559 - 569, 2008/09
The neutron standard field using Am-Be neutron source has been widely used for the routine calibration of neutron dosemeters. The neutron fluence rate at the calibration point is one of the most essential parameters. For the precise determination of the neutron fluence rate, the effect defined as an anisotropic emission from the neutron source, F
(
), should be taken into account. For the proper calibration of the neutron dosemeters used in the Japan Atomic Energy Agency (JAEA), the anisotropic factor F(90) from an Am-Be neutron source was experimentally determined using the precision long counter. Before the determination of the anisotropic factor of the Am-Be source with the protection case, the measured angular distribution from the X3 type Am-Be source was compared with the result obtained by other researchers and with the Monte Carlo calculation using MCNP-4C, for the verification of the method the authors adopted.
O-moderated 
Cf sourceKowatari, Munehiko; Fujii, Katsutoshi; Takahashi, Masa; Yoshizawa, Michio; Shimizu, Shigeru; Kawasaki, Katsuya; Yamaguchi, Yasuhiro
Radiation Protection Dosimetry, 126(1-4), p.138 - 144, 2007/08
Times Cited Count：5 Percentile：37.19(Environmental Sciences)The facility of the Radiation Standards (FRS) of the Japan Atomic Energy Agency was equipped with the reference neutron field by using DO moderated Cf neutron source (DO-Cf), with a 30cm diameter DO sphere. In order to determine the characteristics of the reference field within the ranges of calibration distance (75 to 200 cm from the center of the source to the calibration point) in detail, the authors performed the evaluation of the neutron spectra and neutron fluence rate at various distances from the DO moderated source assembly by computations using MCNP-4C and by experimental studies using Bonner Multi-sphere neutron Spectrometer (BMS). Due to the volume neutron source, it is difficult to measure the contribution of the scattered neutron component with the desirable accuracy by shadow-cone method. In this study, the net counting rate of each counter of BMS was corrected by estimating the ratio of the counting rate of each counter in condition of the experimental and the ideal arrangement by the Monte Carlo calculation. The spectra of the direct component were unfolded by using the corrected counting rate with SAND II code. The averaged dose conversion coefficients (h
(10) and h
(10)) and neutron dose rates (H(10) and H(10)) at various distance were estimated based on the measured spectra. The effectiveness of the correction was discussed by comparing the measured and calculated values. Additionally, the suitable distance for the calibration of personal dosimeter at FRS reference field was evaluated by the results.
Fujii, Katsutoshi; Kowatari, Munehiko; Kawasaki, Katsuya
Hoken Butsuri, 41(3), p.175 - 179, 2006/09
no abstracts in English
Fujii, Katsutoshi; Kawasaki, Katsuya; Kowatari, Munehiko; Tanimura, Yoshihiko; Kajimoto, Yoichi; Shimizu, Shigeru
JAEA-Testing 2006-005, 146 Pages, 2006/08
JAEA-Testing-2006-005.pdf:19.71MB
4MV Van de Graff accelerator was installed in the Facility of Radiation Standards (FRS) in June 2000, and monoenergetic neutron calibration fields and high energy 
-ray calibration fields have been developed. The calibration fields are provided for R&D on dosimetry, and for the calibration and type-test of radiation protection instruments. This article describes the operational procedure, the maintenance work and the operation of the related apparatuses of the accelerator. This article focuses on the sufficient safety and radiation control for the operators, the maintenance performance of the accelerator, and on the prevention of the malfunction due to the mistakes of the operator. This article targets the unexperienced engineers in charge of operation and maintenance of the accelerator.
Kawasaki, Katsuya
Hoken Butsuri, 40(1), p.56 - 60, 2005/03
The centralized radioactivity measurement system has been used to carry out intensively measurements of a large number and variety of samples that are necessary for the control of radioactivity in the facilities of the JAERI Tokai Establishment and its environment. The operation of the system started in 1981, and presently the system processes more than 20,000 samples a year. However, the computers of the system have aged so much that the manufacturer's support and stable operation are no longer sure. Therefore, we renewed and restructured the computer system in 2003. A client-server system was adopted in the new system. The information of samples can be registered through the intranet. The clients can also confirm the progress of processing of their samples and browse the analytical results from their own computers. The renewed system can provide some convenience functions to the clients. This report is introduced about the centralized radioactivity measurement system.
Kawasaki, Katsuya; Mochizuki, Kaoru*; Suzuki, Takehiko; Kinouchi, Nobuyuki
JAERI-Tech 2004-070, 50 Pages, 2004/12
JAERI-Tech-2004-070.pdf:18.19MB
The centralized radioactivity measurement system has been used to carry out intensively measurements of a large number and variety of samples that are necessary for the control of radioactivity in the facilities of the JAERI Tokai Establishment and its environment. The operation of the system started in 1981, and presently the system processes more than 20,000 samples a year. However, the computers of the system have aged so much that the manufacturer's support and stable operation are no longer sure. Therefore, we renewed and restructured the computer system in 2003. A client-server system was adopted in the new system. The information of samples can be registered through the intranet. The clients can also confirm the progress of processing of their samples and browse the analytical results from their own computers. The renewed system can provide some convenience functions to the clients.
Saegusa, Jun; Kawasaki, Katsuya; Mihara, Akira; Ito, Mitsuo; Yoshida, Makoto
Applied Radiation and Isotopes, 61(6), p.1383 - 1390, 2004/12
Times Cited Count：28 Percentile：84.49(Chemistry, Inorganic & Nuclear)no abstracts in English
H and 
C induced in concrete shielding of an electron accelerator facilityEndo, Akira; Harada, Yasunori; Kawasaki, Katsuya; Kikuchi, Masamitsu
Applied Radiation and Isotopes, 60(6), p.955 - 958, 2004/06
Times Cited Count：7 Percentile：45.11(Chemistry, Inorganic & Nuclear)no abstracts in English
-ray efficiency curves for volume samples by the combination of Monte Carlo simulations and point source calibrationSaegusa, Jun; Oishi, Tetsuya; Kawasaki, Katsuya; Yoshizawa, Michio; Yoshida, Makoto; Sawahata, Tadahiro*; Honda, Tetsutaro*
Journal of Nuclear Science and Technology, 37(12), p.1075 - 1081, 2000/12
no abstracts in English
*; Oi, Yoshihiro; Taki, Mitsumasa; Kawasaki, Katsuya; Yoshida, Makoto
Applied Radiation and Isotopes, 50(6), p.1057 - 1061, 1999/00
Times Cited Count：8 Percentile：53.62(Chemistry, Inorganic & Nuclear)no abstracts in English
-ray emitters induced in the concrete shield of the JAERI electron linac facilityEndo, Akira; Kawasaki, Katsuya; Kikuchi, Masamitsu; Harada, Yasunori
JAERI-Tech 97-027, 28 Pages, 1997/07
no abstracts in English
-counting system used for determining surface emission rate of calibration sources in radiation protection measurementsYoshida, Makoto; Kawasaki, Katsuya;
Radioisotopes, 41(6), p.316 - 319, 1992/06
no abstracts in English
-scanner and its characters; Kawasaki, Katsuya; Minami, Kentaro
JAERI-M 90-069, 46 Pages, 1990/04
no abstracts in English
Onuma, Isamu; Kawasaki, Katsuya; Kowatari, Munehiko; Yasu, Katsuji; Okura, Takehisa; Kajimoto, Yoichi; Shimizu, Shigeru
no journal, ,
no abstracts in English
Ogose, Hitoshi; Kawasaki, Katsuya; Kajimoto, Yoichi
no journal, ,
no abstracts in English
Am-Be neutron sourceKowatari, Munehiko; Onuma, Isamu; Kawasaki, Katsuya; Tanimura, Yoshihiko; Saegusa, Jun; Yoshizawa, Michio
no journal, ,
no abstracts in English
Tatebe, Yosuke; Onuma, Isamu; Kawasaki, Katsuya; Kowatari, Munehiko; Sawahata, Tadahiro; Sato, Yasuo; Yoshizawa, Michio
no journal, ,
no abstracts in English
Am-Be neutron standard fields using new and old sourcesKowatari, Munehiko; Tatebe, Yosuke; Sato, Yasuo; Kawasaki, Katsuya; Yoshizawa, Michio
no journal, ,
For the contribution to the effective operation of Am-Be neutron standard fields, experimental studies on the comparison of the calibration factors for neutron dosemeters by old and new sources were made. Measured calibration factors for each dosemeter were compared by estimating their E
values. Results of the variation of calibration factor for neutron dosemeters were quite satisfactory and identical calibration factors were obtained at neutron calibration fields by new and old Am-Be source.
Tatebe, Yosuke; Kowatari, Munehiko; Tanimura, Yoshihiko; Kawasaki, Katsuya; Yoshizawa, Michio; Im, G. S.*; Kim, S.*; Lee, J.*; Kim, B.-H.*
no journal, ,
no abstracts in English
