Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
-ray analysisKinoshita, Norikazu*; Noto, Takuma*; Nakajima, Hitoshi*; Kosako, Kazuaki*; Kato, Takahiro*; Kuroiwa, Yoichi*; Kurabe, Misako*; Sasaki, Yuki*; Torii, Kazuyuki*; Maeda, Makoto; et al.
Journal of Radioanalytical and Nuclear Chemistry, 332(2), p.479 - 486, 2023/02
(Al,Ga)
O
scintillator Compton camera mounted on an unmanned helicopterShikaze, Yoshiaki; Nishizawa, Yukiyasu; Sanada, Yukihisa; Torii, Tatsuo; Jiang, J.*; Shimazoe, Kenji*; Takahashi, Hiroyuki*; Yoshino, Masao*; Ito, Shigeki*; Endo, Takanori*; et al.
Journal of Nuclear Science and Technology, 53(12), p.1907 - 1918, 2016/12
Times Cited Count：37 Percentile：96.48(Nuclear Science & Technology)The Compton camera was improved for use with the unmanned helicopter. Increase of the scintillator array from 4
4 to 88 and expanse of the distance between the two layers contributed to the improvements of detection efficiency and angular resolution, respectively. Measurements were performed over the riverbed of the Ukedo river of Namie town in Fukushima Prefecture. By programming of flight path and speed, the areas of 65 m 60 m and 65 m 180 m were measured during about 20 and 30 minutes, respectively. By the analysis the air dose rate maps at 1 m height were obtained precisely with the angular resolution corresponding to the position resolution of about 10 m from 10 m height. Hovering flights were executed over the hot spot areas for 10-20 minutes at 5-20 m height. By using the reconstruction software the -ray images including the hot spots were obtained with the angular resolution same as that evaluated in the laboratory (about 10
).
Tsuchiya, Harufumi*; Enoto, Teruaki*; Torii, Tatsuo; Nakazawa, Kazuhiro*; Yuasa, Takayuki*; Torii, Shunsuke*; Fukuyama, Taro*; Yamaguchi, Takahiro*; Kato, Hiroshi*; Okano, Shinji*; et al.
Physical Review Letters, 102(25), p.255003_1 - 255003_4, 2009/06
Times Cited Count：71 Percentile：90.38(Physics, Multidisciplinary)During thunderstorms on 2008 September 20, a simultaneous detection of -rays and electrons was made at a mountain observatory in Japan located 2770 m above sea level. Both emissions, lasting 90 seconds, were associated with thunderclouds rather than lightning. The photon spectrum, extending to 10 MeV, can be interpreted as consisting of bremsstrahlung -rays arriving from a source which is 60-130 m in distance at 90% confidence level. The observed electrons are likely to be dominated by a primary population escaping from an acceleration region in the clouds.
Shikaze, Yoshiaki; Torii, Tatsuo; Shimazoe, Kenji*; Jiang, J.*; Takahashi, Hiroyuki*; Kurosawa, Shunsuke*; Kamada, Kei*; Yoshikawa, Akira*; Yoshino, Masao*; Ito, Shigeki*; et al.
no journal, ,
no abstracts in English
Shikaze, Yoshiaki; Torii, Tatsuo; Nishizawa, Yukiyasu; Yoshida, Mami*; Shimazoe, Kenji*; Jiang, J.*; Takahashi, Hiroyuki*; Kurosawa, Shunsuke*; Kamada, Kei*; Yoshikawa, Akira*; et al.
no journal, ,
no abstracts in English
Kodama, Shohei*; Kurosawa, Shunsuke*; Morishita, Yuki; Usami, Hiroshi; Hayashi, Masateru*; Tanaka, Hiroki*; Yoshino, Masao*; Kamada, Kei*; Yoshikawa, Akira*; Torii, Tatsuo
no journal, ,
After Fukushima 1st Nuclear Plant accident, a large number of radioactive pollutants or nuclear debris with very high dose of more than a few Sv/h still have existed. To estimate the dose of such pollutants, a Japan Atomic Energy Agency research group has suggested a new technique to use a long optical fiber and a red-emitting scintillator, and the scintillation photons are read outside of high dose area. We tested the gamma-ray detection performance of a ruby (Cr:Al
O) and a newly developed CsHfI
scintillators as a scintillating probe coupled with an optical fiber in this study.
Torii, Tatsuo; Sanada, Yukihisa; Kurosawa, Shunsuke*; Hayashi, Takashi*; Sakagami, Takahide*; Kodama, Shyohei*
no journal, ,
In the decommissioning of the Fukushima Daiichi Nuclear Power Plant, non-destructive inspection of piping inside and outside the facility and inspection of contamination inside the piping after removal of the piping is an important issue. In order to set targets for nondestructive inspection inside the piping, we interviewed TEPCO and confirmed the following conditions: the diameters of pipes commonly used in the 1F facility (500A and 25A), hydrogen gas containing 
-ray emitting nuclides, deposits, and moisture inside the pipes. Based on this situation, the two major themes of the research design were nondestructive inspection for internal penetration and radiological imaging. In this series of presentations, we will introduce the research plan and some of the results related to radiation imaging.
