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Yoshitomi, Hiroshi
FBNews, (557), p.1 - 5, 2023/05
no abstracts in English
Tanimura, Yoshihiko; Yoshizawa, Michio
Radiation Protection Dosimetry, 180(1-4), p.417 - 421, 2018/08
Times Cited Count：0 Percentile：0.01(Environmental Sciences)A high efficiency proton recoil telescope (PRT), which consists of a radiator, a 
E detector and an E detector, was developed to determine the neutron fluence in the 14.8 MeV mono-energetic neutron field at the FRS. A 2 mm thick plastic scintillation detector was employed as the radiator to increase the detection efficiency and compensate the energy loss of the recoil proton in the radiator. A thin and a thick silicon detectors with 150 
m and 3 mm thick sensitive layers were employed as the E and E detectors, respectively. The detection efficiency was evaluated by the neutron measurements in the 14.8 MeV field for the distances from the radiator to E detector of 50 mm, 100 mm and 150 mm. The detection efficiency increases up to 3.7 
10
with the decrease in the distance, which is roughly a few orders of magnitude greater than those of common PRTs. These detection efficiencies are high enough to determine the neutron fluence at the 14.8 MeV field within a few hours.
Uchida, Yoshiaki*; Saegusa, Jun; Kajimoto, Yoichi; Tanimura, Yoshihiko; Shimizu, Shigeru; Yoshizawa, Michio
JAERI-Tech 2005-012, 31 Pages, 2005/03
JAERI-Tech-2005-012.pdf:4.58MB
no abstracts in English
Yamamoto, Hideaki
Kasokuki, 1(3), 294 Pages, 2004/12
no abstracts in English
Ono, Akio*
Kaku Busshitsu Kanri Senta Nyusu, 33(9), p.12 - 15, 2004/09
no abstracts in English
Saegusa, Jun; Tanimura, Yoshihiko; Yoshizawa, Michio
Proceedings of 11th International Congress of the International Radiation Protection Association (IRPA-11) (CD-ROM), 8 Pages, 2004/05
Relationships between dosemeter readings and the true dose equivalents at various workplaces were analyzed. From the analysis, it was shown that depending on the types of dosemeters, there exist a suitable calibration field, and the field differs by the difference of response characteristics of dosemeters. For the precise estimation of dose equivalent, it is important that measurement is carried out under the careful considerations of the difference between neutron spectrum at workplace and at calibration field, as well as the improvement of response characteristics of the dosemeters.
Shu, Wataru; Matsuyama, Masao*; Suzuki, Takumi; Nishi, Masataka
Nuclear Instruments and Methods in Physics Research A, 521(2-3), p.423 - 429, 2004/04
Times Cited Count：19 Percentile：75.21(Instruments & Instrumentation)The characteristics of a promising tritium process monitor using a NaI(Tl) scintillation detector for X-rays was examined with pure tritium in a concentration range of 10
-10
GBq/m
. The measurement of tritium concentration was achieved by observing the bremsstrahlung X-rays generated by the interaction between the tritium beta particles and a gold film coated on the inside of beryllium window. A linear relationship between the counting rate of bremsstrahlung X-rays and the tritium concentration was observed for tritium concentration range of 10-10
GBq/m, and the sensitivity of the monitor was determined to be about 0.5GBq/m per cpm in this concentration range. The characteristics were also investigated with a tritium mixture diluted with deuterium (atomic ration of tritium: 0.83%), and He release from a uranium bed during heating was traced with this monitor.
counting using mathematical simulationKinase, Sakae
RIST News, (37), p.10 - 19, 2004/03
no abstracts in English
Murakami, Hiroyuki; Minami, Kentaro*
Radioisotopes, 53(3), p.197 - 205, 2004/03
no abstracts in English
Shimizu, Shigeru; Fujii, Katsutoshi; Kajimoto, Yoichi; Kawasaki, Tomokatsu; Yamamoto, Hideaki
Dai-16-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.32 - 35, 2004/02
no abstracts in English
Saegusa, Jun; Yoshizawa, Michio; Tanimura, Yoshihiko; Yoshida, Makoto; Yamano, Toshiya*; Nakaoka, Hiroshi*
Nuclear Instruments and Methods in Physics Research A, 516(1), p.193 - 202, 2004/01
Times Cited Count：16 Percentile：70(Instruments & Instrumentation)Energy responses of three types of Japanese rem counters were evaluated by Monte Carlo simulations and measurements. The energy responses for thermal neutrons, monoenergetic neutrons with energies up to 15.2 MeV were evaluated as well as for neutrons from such radionuclide sources as 
Cf. The calculated results were corroborated with the measured ones. Angular dependence of the response and dose equivalent response was also evaluated. As a result, the reliable energy responses were obtained by careful simulations of the proportional counter, moderator and absorber of the rem counters. Furthermore, discussions were made about the relationship between pressure of counting gas and sensitivity of the rem counter. By using the obtained responses, relations of predicted readings of the rem counters and true dose equivalent were studied for various workplace spectra.
Am in the lungKinase, Sakae; Oi, Yoshihiro; Sekiguchi, Masato
Radioisotopes, 52(8), p.378 - 382, 2003/08
no abstracts in English
Fujikawa, Seigo; Okubo, Minoru; Nakazawa, Toshio; Kawasaki, Kozo; Iyoku, Tatsuo
Nihon Genshiryoku Gakkai Wabun Rombunshi, 1(4), p.361 - 372, 2002/12
no abstracts in English
Yoshizawa, Michio
Hokeikyo Nyusu, (29), p.2 - 5, 2002/05
no abstracts in English
Yamanaka, Haruhiko; Hayashi, Kazuhiko; Motohashi, Jun; Kawashima, Kazuhito; Ichimura, Toshiyuki; Tamai, Kazuo; Takeuchi, Mitsuo
JAERI-Tech 2001-084, 110 Pages, 2002/01
JAERI-Tech-2001-084.pdf:10.15MB
no abstracts in English
Saegusa, Jun; Yoshizawa, Michio; Tanimura, Yoshihiko; Yoshida, Makoto
Radioisotopes, 51(1), p.26 - 33, 2002/01
no abstracts in English
Yoshizawa, Michio; Saegusa, Jun; Tanimura, Yoshihiko; Yoshida, Makoto
Proceedings of 14th Meeting of Consultative Committee for Ionizing Radiation, 5 Pages, 2002/00
no abstracts in English
Saegusa, Jun
Hokeikyo Nyusu, (28), p.2 - 5, 2001/10
no abstracts in English
Co 
-ray high dose rate at radiation processing levelKojima, Takuji; Tachibana, Hiroyuki; Haneda, Noriyuki; Kaneko, Hirohisa; Haruyama, Yasuyuki; Tanaka, Ryuichi*
Radioisotopes, 50(7), p.291 - 300, 2001/07
Plaque type 
Co -ray sources having wide radiation field with high absorbed dose rates ranging of about 100
10,000Gy/h is widely used in radiation processing e.g. radiation sterilization of health care products. Calibration of such radiation processing doses or dose rates is not easy to be performed at the present standard dosimetry laboratories, since characteristics of most of their radiation field can provide collimated gamma-rays from a point source and/or lower dose rates, which are quite different from those of panoramic (uncollimated) radiation fields used in radiation processing. The high-dose calibration technique using a parallel-plate ionization chamber system has developed in the JAERI dose calibration facility. The facility equips two Co -ray plaque sources covering wide dose-rate range of 520,000 Gy/h which have overlapping dose-rate region with that at the National Institute of Advanced Industrial Science and Technology(AIST), the national standard Dosimetry laboratory in Japan. Consistency of dose calibration results at JAERI and those at AIST was verified without additional correction regarding to difference in characteristics of radiation fields involving current/exposure -rate conversion coefficients given in the dose rate level of 10100 Gy/h at the AIST and high-dose rates of 520,000 Gy/h at JAERI. It demonstrates our dose traceability to the AIST from the technical point of view. The dose calibration at JAERI covers the high-dose range of 0.5 to 
Gy with uncertainty of 
2.2% at 95% confidence level.
Yoshida, Makoto; Saito, Kimiaki
Nihon Genshiryoku Gakkai-Shi, 43(4), P. 311, 2001/04
no abstracts in English
