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Sanada, Yukihisa; Nishizawa, Yukiyasu*; Ochi, Kotaro; Yuki, Yoichi*; Ishizaki, Azusa; Osada, Naoyuki*
JAEA-Research 2018-009, 48 Pages, 2019/01
At the accident of nuclear facilities, a prediction of the behavior of released radioactive plume is indispensable to make a decision on a refuge plan of inhabitants. Currently, prediction system which is based on atmospheric dispersion simulation has been implemented as a tool of the atomic energy disaster prevention. However, the direct measurement method of the radioactive plume has not existed. In this study, some component technologies were developed for the establishment of direct measurement methods of radioactive plume using unmanned aerial vehicle whose technological innovation is remarkable. In addition, the spray test using mock aerosol was conducted to obtaining the deposition rate to the airplane body. The algorism of making a flight plan was developed based on a prediction model of the radioactive plume. This report summarized the outcome of the second year of the three-year plan.
Sanada, Yukihisa; Mori, Airi; Ishizaki, Azusa; Munakata, Masahiro; Nakayama, Shinichi; Nishizawa, Yukiyasu; Urabe, Yoshimi; Nakanishi, Chika; Yamada, Tsutomu; Ishida, Mutsushi; et al.
JAEA-Research 2015-006, 81 Pages, 2015/07
By the nuclear disaster of Fukushima Daiichi Nuclear Power Station (NPS), Tokyo Electric Power Company (TEPCO), caused by the East Japan earthquake and the following tsunami occurred on March 11, 2011, a large amount of radioactive materials was released from the NPP. These results of the aerial radiation monitoring using the manned helicopter in the fiscal 2014 were summarized in the report.
Sanada, Yukihisa; Kondo, Atsuya*; Sugita, Takeshi*; Nishizawa, Yukiyasu; Yuki, Yoichi*; Ikeda, Kazutaka*; Shoji, Yasunori*; Torii, Tatsuo
Exploration Geophysics, 45(1), p.3 - 7, 2014/11
Times Cited Count:35 Percentile:70.70(Geochemistry & Geophysics)The Great East Japan Earthquake on March 11, 2011 generated a series of large tsunami waves that resulted serious damage to the Fukushima Daiichi Nuclear Power Plant (NPP) and a large amount of radioactive materials were discharged from the NPP to the environment. In recent years, technologies for an unmanned helicopter have been developed and applied to various fields. In expectation of the application of the unmanned helicopter to airborne radiation monitoring, we had developed a radiation monitoring system. Then, we measured the radiation level by using unmanned helicopter in soil contaminated areas by radioactive cesium emitted from the NPP to evaluate ambient dose-rate distribution around the areas. Here, we reports on the measurement technique and the result.
Sanada, Yukihisa; Nishizawa, Yukiyasu; Urabe, Yoshimi; Yamada, Tsutomu; Ishida, Mutsushi; Sato, Yoshiharu; Hirayama, Hirokatsu; Takamura, Yoshihide; Nishihara, Katsuya; Imura, Mitsuo; et al.
JAEA-Research 2014-012, 110 Pages, 2014/08
By the nuclear disaster of Fukushima Daiichi Nuclear Power Station (NPS), Tokyo Electric Power Company (TEPCO), caused by the East Japan earthquake and the following tsunami occurred on March 11, 2011, a large amount of radioactive materials was released from the NPP. This document was summarized in the results of the aerial radiation monitoring using the manned helicopter in the fiscal 2013.
Mori, Michiaki; Yogo, Akifumi; Kiriyama, Hiromitsu; Nishiuchi, Mamiko; Ogura, Koichi; Orimo, Satoshi; Ma, J.*; Sagisaka, Akito; Kanazawa, Shuhei; Kondo, Shuji; et al.
IEEE Transactions on Plasma Science, 36(4), p.1872 - 1877, 2008/08
Times Cited Count:8 Percentile:27.70(Physics, Fluids & Plasmas)A dependence of cut-off proton kinetic energy on laser prepulse duration has been observed. ASE pedestal duration is controlled by a fast electro-optic pulse slicer where the risetime is estimated to be 130 ps. We demonstrate a new correlated spectral technique for determining this risetime using a stretched, frequency chirped pulse.
Hasegawa, Ken; Matsuoka, Toshiyuki; Yuki, Yoichi*
Shadan Hojin Butsuri Tansa Gakkai Dai-116-Kai (Heisei-19-Nendo Shunki) Gakujutsu Koenkai Rombunshu, p.163 - 166, 2007/05
Airborne magnetic and radiometric surveys were conducted in the region of the Toki granite. The shaded relief map of the magnetic survey data shows that the magnetic susceptibility of the Toki granite is not uniform, and a relatively high magnetic susceptibility zone was identified. Moreover, it was shown that the Toki granite can be separated into three parts; one with high U abnormality, another with high Th abnormality, both separated by a middle region. The area with high magnetic susceptibility in the Toki granite correspond to where the thickness of the layer of the Mizunami and/or the Seto Group is thin and the depth of the Toki granite is shallow, and the region corresponds to high U abnormality. We conclude the Toki Granite is not homogeneous with respect to geophysical properties, but instead is composed of separate regions.
Hasegawa, Ken; Matsuoka, Toshiyuki; Yuki, Yoichi*
Shadan Hojin Butsuri Tansa Gakkai Dai-116-Kai (Heisei-19-Nendo Shunki) Gakujutsu Koenkai Rombunshu, p.159 - 162, 2007/05
An airborne electromagnetic survey was conducted in the region of the Toki granite. The resistivity of the Toki granite about is about 5000 m while the resistivity of the Mizunami Group and the Seto Group which overlie the Toki granite is tens of
m. Due to processing limitation, this large contrast in resistivity was not included in past calculations of apparent resistivity. A new calculation method for apparent resistivity was developed, and data was reprocessed. As a result, the regions where the thickness of the Mizunami and/or the Seto Group is thin (the depth of the Toki granite is shallow) and the regions where the Toki granite is deep were clearly identified.
Daido, Hiroyuki; Sagisaka, Akito; Ogura, Koichi; Orimo, Satoshi; Nishiuchi, Mamiko; Mori, Michiaki; Ma, J.-L.; Pirozhkov, A. S.; Kiriyama, Hiromitsu; Kanazawa, Shuhei; et al.
Proceedings of 7th Pacific Rim Conference on Lasers and Electro-Optics (CLEO-PR 2007) (CD-ROM), p.77 - 79, 2007/00
We are developing a proton accelerator using an intense lasers with a focused intensity of 10
W/cm
. To monitor proton energy spectra as well as plasma parameters at each laser shot, we are using real time detectors. The proton energy of MeV is stably obtained for applications.
Sanada, Yukihisa; Torii, Tatsuo; Kondo, Atsuya; Ikeda, Kazutaka*; Yuki, Yoichi*
no journal, ,
no abstracts in English
Osada, Naoyuki*; Ishizaki, Azusa; Nishizawa, Yukiyasu*; Yuki, Yoichi*; Sanada, Yukihisa
no journal, ,
no abstracts in English
Yogo, Akifumi; Mori, Michiaki; Kiriyama, Hiromitsu; Ogura, Koichi; Sagisaka, Akito; Orimo, Satoshi; Pirozhkov, A. S.; Esirkepov, T. Z.; Bulanov, S. V.; Kanazawa, Shuhei; et al.
no journal, ,
no abstracts in English
Yogo, Akifumi; Daido, Hiroyuki; Mori, Michiaki; Sagisaka, Akito; Ogura, Koichi; Orimo, Satoshi; Kiriyama, Hiromitsu; Pirozhkov, A. S.; Kanazawa, Shuhei; Nakai, Yoshiki; et al.
no journal, ,
We report the result on a novel online analysis of fast ions generated in an ultraintense laser-foil interaction. Fast protons are observed by a time-of-flight (TOF) detector, which is precisely calibrated using proton beams from an ion accelerator as to its detection efficiency depending on the proton energy. The TOF detector provides shot-to-shot energy distributions of protons immediately after the irradiation of a high-intensity laser pulse of 10 W/cm
. Definite correlations are found between the prepulse intensity and the high energy cutoff of protons as well as the conversion efficiency of the laser energy into the proton energy, governing the stability of the repetitive proton generation.
Orimo, Satoshi; Yogo, Akifumi; Ogura, Koichi; Sagisaka, Akito; Mori, Michiaki; Kiriyama, Hiromitsu; Kondo, Shuji; Yamamoto, Yoichi*; Shimomura, Takuya*; Tanoue, Manabu*; et al.
no journal, ,
We are investigating an intense fs-laser driven MeV proton source using a thin foil, and its applications. Simultaneous imaging of a sample with a proton and an X-ray beams has been demonstrated by a ultra-short pulse higt intensity Ti:Sapphire laser systems at JAEA and GIST. For generating a short-pulse proton beams and X-rays, an intense laser pulse irradiates a tape targets. The p-polarized laser pulse with 50 mm diameter is focused onto the cupper tape target at 45 degree incident angle with focal length of 238 mm (F/4.8), giving an intensity on target of 3-910
W/cm10
. The cupper and polyimide tape was 5, 7.5 micron in thickness and 20 mm in width. The target system supplies a fresh surface to the focus spot at every shot. We obtained simultaneously the projection image of a Ni mesh pattern having a periodically structured pattern by the proton detected CR39 and X-rays detected on imaging plate.
Yogo, Akifumi; Mori, Michiaki; Ogura, Koichi; Sagisaka, Akito; Orimo, Satoshi; Kanazawa, Shuhei; Kondo, Shuji; Nakai, Yoshiki; Akutsu, Atsushi; Yamamoto, Yoichi*; et al.
no journal, ,
no abstracts in English
Mori, Michiaki; Yogo, Akifumi; Orimo, Satoshi; Ogura, Koichi; Sagisaka, Akito; Nakamura, Shu*; Shirai, Toshiyuki*; Iwashita, Yoshihisa*; Noda, Akira*; Oishi, Yuji*; et al.
no journal, ,
no abstracts in English
Ogura, Koichi; Orimo, Satoshi; Sagisaka, Akito; Nishiuchi, Mamiko; Mori, Michiaki; Yogo, Akifumi; Kiriyama, Hiromitsu; Kanazawa, Shuhei; Kondo, Shuji; Nakai, Yoshiki; et al.
no journal, ,
When the high energy proton beam was generated by the high intensity laser system, the image of the plasma produced by the laser system was measured with an X-ray pinhole camera system. The proton beam, which has maximum energy, was generated in the vicinity of the target position where the image size of the plasma was the smallest.
Mori, Michiaki; Ogura, Koichi; Sagisaka, Akito; Orimo, Satoshi; Takai, Mamiko; Yogo, Akifumi; Kiriyama, Hiromitsu; Ma, J.-L.; Kanazawa, Shuhei; Kondo, Shuji; et al.
no journal, ,
no abstracts in English
Sanada, Yukihisa; Kondo, Atsuya; Sugita, Takeshi; Yuki, Yoichi*; Torii, Tatsuo
no journal, ,