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Koizumi, Mitsuo; Takahashi, Tone; Hironaka, Kota; Mochimaru, Takanori*; Yamaguchi, Ikuto*; Kimura, Yoshiki; Tanigaki, Minoru*; Masaki, Hiroko*; Harada, Hiroshi*; Goto, Jun*; et al.
Proceedings of INMM & ESARDA Joint Annual Meeting 2023 (Internet), 7 Pages, 2023/05
*(10) dose rates measured in environment contaminated by radioactive caesium; Correction of directional dependence of scintillation detectorsTsuda, Shuichi; Tanigaki, Minoru*; Yoshida, Tadayoshi; Okumura, Ryo*; Saito, Kimiaki
Radiation Protection Dosimetry, 193(3-4), p.228 - 236, 2021/03
Times Cited Count：3 Percentile：37.09(Environmental Sciences)Environmental dose rate monitoring has been performed with various scintillation detectors since the Fukushima Dai-ichi Nuclear Power Plant accident. Gamma-rays from caesium isotopes deposited in soil enter radiation detectors in any direction, but directional dependence of the detectors used for dose rate measurements are not always uniform and the dose rates vary even if measurement takes place at the same place. To investigate the influence of crystal configurations on dose rate, dose rate measurements using several scintillation detectors with different crystal configurations were conducted. By measuring pulse height spectra and multiplying them with spectrum - dose conversion operators (G(E) function), dose rates were deduced and compared. It was found that the dose rates varied within approximately 25% among six detectors. To reduce the differences, the dose rate using G(E) functions determined in rotational geometry were obtained and applied instead. The revised dose rates agreed with one another within uncertainties, but this was not the case of scintillation detector with flat crystal shape, and it means this method could not compensate its strong directional dependence. These experimental results reveal that detectors with superior directional characteristics should be used for environmental dose rate measurement since the compensation of directional dependence using a G(E) function determined in rotational geometry is not always available.
Sonoda, Tetsu*; Katayama, Ichiro*; Wada, Michiharu*; Iimura, Hideki; Sonnenschein, V.*; Iimura, Shun*; Takamine, Aiko*; Rosenbusch, M.*; Kojima, Takao*; Ahn, D. S.*; et al.
Progress of Theoretical and Experimental Physics (Internet), 2019(11), p.113D02_1 - 113D02_12, 2019/11
Times Cited Count：1 Percentile：10.61(Physics, Multidisciplinary)An in-flight separator, BigRIPS, at RIBF in RIKEN provides each experiment with specific nuclides separated from many nuclides produced by projectile fragmentation or in-flight fission. In this process, nuclides other than separated ones are discarded on the slits in BigRIPS, although they include many nuclides interested from the view point of nuclear structure. In order to extract these nuclides for parasitic experiments, we are developing a method using laser ion-source (PALIS). A test experiment with 
Se beam from RIBF has been performed by using a gas cell set in BigRIPS. Unstable nuclides around 
Se were stopped in the gas cell in accordance with a calculation using LISE code. The stopping efficiency has been estimated to be about 30%. As a next step, we will establish the technique for extracting reaction products from the gas cell.
Tsuda, Shuichi; Tanigaki, Minoru*; Yoshida, Tadayoshi; Saito, Kimiaki
Hoshasen, 44(3), p.109 - 118, 2018/11
JAEA has started to perform dose rate monitoring using a car-borne survey system KURAMA to rapidly produce the dose rate mappings of the deposited radionuclides in the environment after the Fukushima Dai-ichi Nuclear Power Plant accident. KURAMA is a car-borne survey system developed by Kyoto University to perform dose rate monitoring in a wide area in detail with rapidity. By improving KURAMA with continuous dose rate monitoring, the 2nd generation of KURAMA (KURAMA-II) succeeded in downsizing, durability and automated transmission of data so that enable detailed dose rate mapping in wide area in shorter period of time. This paper reports the radiation characteristics and the simulation analysis of KURAMA-II on the special issue of Hoshasen, the journal of Ionization Radiation Division in the Japan society of applied physics.
Tsuda, Shuichi; Tanigaki, Minoru*; Yoshida, Tadayoshi; Okumura, Ryo*; Saito, Kimiaki
Nihon Genshiryoku Gakkai Wabun Rombunshi, 17(1), p.11 - 17, 2018/03
Environmental dose rate monitoring has been performed using scintillation detectors since the Fukushima Dai-ichi Nuclear Power Plant accident happened. After the accident, various scintillation detectors with directional dependence are used in the measurement, though detectors with superior directional dependence are needed because photons come from various direction in the environment. To investigate the influence of crystal configurations on indicated values of dose rates, pulse height spectra were measured using scintillation-based detectors with different crystal configurations and ambient dose rates were obtained using a spectrum - dose conversion operator (G(E) function). It is found that the dose rate for a rectangular-parallelepiped crystal is 
40% than that for a cylindrical one at the maximum. However, the values agreed within 10% among all the detectors irrespective of the crystal shapes, using G(E) functions determined in a rotational irradiation geometry.
Tsuda, Shuichi; Yoshida, Tadayoshi; Ando, Masaki; Matsuda, Norihiro; Mikami, Satoshi; Tanigaki, Minoru*; Okumura, Ryo*; Takamiya, Koichi*; Sato, Nobuhiro*; Seki, Akiyuki; et al.
Radioisotopes, 64(4), p.275 - 289, 2015/04
This article provides practically useful information on air dose rate measurements in the environments. The basic requirements for the accurate measurements are described giving actual data. The characteristics and some measured results are shown for reliable methods which are widely used in the environmental radiation measurements. Further, information is given on internet sites where air dose rates and related data obtained by official organizations can be browsed.
Ando, Masaki; Nakahara, Yukio; Tsuda, Shuichi; Yoshida, Tadayoshi; Matsuda, Norihiro; Takahashi, Fumiaki; Mikami, Satoshi; Kinouchi, Nobuyuki; Sato, Tetsuro*; Tanigaki, Minoru*; et al.
Journal of Environmental Radioactivity, 139, p.266 - 280, 2015/01
Times Cited Count：55 Percentile：82.64(Environmental Sciences)A series of car-borne surveys using the KURAMA and KURAMA-II systems was conducted in a wide area in eastern Japan from June 2011 to December 2012 to evaluate the distribution of air dose rates around the Fukushima Dai-ichi Nuclear Power Plant, and to determine the time-dependent trend of decrease in air dose rates. An automated data processing system was established, which enables analyses of large amounts of data obtained with the use of about 100 units of the measurement system in a short time. The initial data for studying the migration status of radioactive cesium was obtained in the first survey, followed by the other car-borne surveys having wider measurement ranges. Comparing the measured air dose rates obtained in each survey, it was found that the decreasing trend of air dose rates measured through car-borne surveys was larger than that expected from the physical decay of radioactive cesium and that measured using NaI (Tl) survey meters around the road.
Tsuda, Shuichi; Yoshida, Tadayoshi; Nakahara, Yukio; Sato, Tetsuro; Seki, Akiyuki; Matsuda, Norihiro; Ando, Masaki; Takemiya, Hiroshi; Tanigaki, Minoru*; Takamiya, Koichi*; et al.
JAEA-Technology 2013-037, 54 Pages, 2013/10
JAEA-Technology-2013-037.pdf:4.94MB
JAEA has been performing dose rate mapping in air using a car-borne survey system KURAMA-II. The KURAMA system is a GPS-aided mobile radiation monitoring system that has been newly developed by Kyoto University Research Reactor Institute in response to the nuclear disaster. The KURAMA system is composed of an energy-compensated scintillation survey meter for measuring dose rate, electric device for controlling both the dose rates and the position data from a GPS module, a computer server for processing and analyzing data from KURAMA, and client PCs for providing for end users. The KURAMA-II has been improved in small-packaging, durability, and automated data transmission. In consequence, dose rate mapping in wide area has become possible in shorter period of time. This report describes the construction of KURAMA-II, its application and a suggestion of how to manage a large number of KURAMA-II.
Yamaguchi, Ikuto*; Koizumi, Mitsuo; Takahashi, Tone; Mochimaru, Takanori*; Yoshimi, Yuki*; Yamanishi, Hirokuni*; Wakabayashi, Genichiro*; Tanigaki, Minoru*; Harada, Hiroshi*; Masaki, Hiroko*; et al.
no journal, ,
no abstracts in English
Mochimaru, Takanori*; Koizumi, Mitsuo; Takahashi, Tone; Yamaguchi, Ikuto*; Yoshimi, Yuki*; Yamanishi, Hirokuni*; Wakabayashi, Genichiro*; Tanigaki, Minoru*; Harada, Hiroshi*; Masaki, Hiroko*; et al.
no journal, ,
no abstracts in English
Takemiya, Hiroshi; Saito, Kimiaki; Mizuno, Satoshi*; Tanigaki, Minoru*
no journal, ,
Visualization system for immediately publishing detailed time variation data on the distribution of radioactive substances in Fukushima district is presented. The system visualizes and provides continuous and consecutive air dose rate data measured by devices mounted on buses. It automatically generates scripts for both displaying intuitive distribution data with the help of networked GIS systems and providing graphs on the time variation data in cooperation with web-services. In this presentation, we introduce an outline of the Fukushima air dose measurement project in which the system is utilized, and report elemental technologies for the development of the system.
Sonoda, Shinya*; Takada, Atsushi*; Tanimori, Toru*; Tsuda, Masaya*; Tahara, Keisuke*; Kobayashi, Koichiro*; Tanigaki, Minoru*; Taniguchi, Akihiro*; Nagai, Haruyasu; Nakayama, Hiromasa; et al.
no journal, ,
We have developed an Electron Tracking Compton Camera (ETCC), which provides a well-defined Point Spread Function (PSF) by reconstructing a direction of each gamma as a point and realizes simultaneous measurement of brightness and spectrum of MeV gamma-rays. Here, we present the results of the gamma-imaging-spectroscopy with ETCC tested at the research reactor at the Institute for Integrated Radiation and Nuclear Science, Kyoto University.
Igarashi, Yu; Hamaguchi, Takumi; Maeda, Eita; Yamada, Junya; Muto, Yasunobu; Tanigaki, Minoru*; Nohara, Naofumi
no journal, ,
At the JAEA Oarai Research Establishment, a portable KURAMA equipped with a data transmission function through an autonomous network using the ZETA standard was permanently installed near the MP for the purpose of redundancy in the measurement of monitoring points, and a system for observing radiation doses near the site boundary was developed. In this presentation, we report on the fixed point observation data for about one year using this system.
Takahashi, Tone; Koizumi, Mitsuo; Mochimaru, Takanori*; Yamaguchi, Ikuto*; Yoshimi, Yuki*; Tanigaki, Minoru*; Goto, Jun*; Harada, Hiroshi*; Masaki, Hiroko*; Ito, Fumiaki*
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Koizumi, Mitsuo; Takahashi, Tone; Mochimaru, Takanori*; Yamaguchi, Ikuto*; Yoshimi, Yuki*; Yamanishi, Hirokuni*; Wakabayashi, Genichiro*; Tanigaki, Minoru*; Harada, Hiroshi*; Masaki, Hiroko*; et al.
no journal, ,
no abstracts in English
Tsuda, Shuichi; Tanigaki, Minoru*; Saito, Kimiaki
no journal, ,
A GPS-aided radiation monitoring system KURAMA and the KURAMA-II developed by Kyoto University has been utilized after the Fukushima Dai-ichi Nuclear Power Plant accident in a mapping project of radionuclides deposited in the environment and monitoring of dose rates in air. KURAMA-II has a function of precisely evaluating dose rates in air based on measured pulse-height spectra from the incorporated CsI(Tl) scintillation detector. In this study, to evaluate dose contribution of the radionuclides in the environment, photon energy spectra was estimated by an unfolding method, using the measured pulse-height spectra and the dataset of the calculated response functions of the CsI(Tl) scintillation detector in a simulative environment. The results of dose contributions of artificial and natural radionuclides based on the estimation method will be reported in the session, "Mapping project in Fukushima and related researches".
Sonoda, Shinya*; Takada, Atsushi*; Tanimori, Toru*; Tsuda, Masaya*; Tahara, Keisuke*; Kobayashi, Koichiro*; Tanigaki, Minoru*; Nagai, Haruyasu; Nakayama, Hiromasa; Satoh, Daiki
no journal, ,
We have developed an Electron Tracking Compton Camera (ETCC), which provides a well-defined Point Spread Function (PSF) by reconstructing a direction of each gamma as a point and realizes simultaneous measurement of brightness and spectrum of MeV gamma-rays. Here, we present the results of the gamma-imaging-spectroscopy with ETCC tested at the research reactor at the Institute for Integrated Radiation and Nuclear Science, Kyoto University.
Tsuda, Shuichi; Yoshida, Tadayoshi; Tanigaki, Minoru*; Okumura, Ryo*; Saito, Kimiaki
no journal, ,
Environmental dose rate monitoring has been performed using scintillation detectors since the Fukushima Dai-ichi Nuclear Power Plant accident happened. It is necessary to evaluate the influence of directional dependence on indicated values, because scintillation detectors with such dependence are used, though photons come from various direction in the environment. In this study, pulse height spectra were measured using scintillation detectors with different crystal configurations and ambient dose equivalent rates were obtained using spectrum - dose conversion operators. The ratio of dose rates calculated in a simulated environmental radiation field agrees with the measurement fairly well. The calculated dose rates of CsI(Tl) cylindrical crystals with varying height-to-diameter ratios indicated that the environmental dose rates can be estimated by a simple calibration using a unidirectional beam, provided that a crystal configuration and an irradiation surface are properly selected.
Yoshida, Tadayoshi; Tsuda, Shuichi; Tanigaki, Minoru*; Okumura, Ryo*; Saito, Kimiaki
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no abstracts in English
Takahashi, Tone; Koizumi, Mitsuo; Mochimaru, Takanori*; Yamaguchi, Ikuto*; Yoshimi, Yuki*; Yamanishi, Hirokuni*; Wakabayashi, Genichiro*; Tanigaki, Minoru*; Harada, Hiroshi*; Masaki, Hiroko*; et al.
no journal, ,
no abstracts in English
-ray fieldsYoshida, Tadayoshi; Tsuda, Shuichi; Saito, Kimiaki; Tanigaki, Minoru*
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no abstracts in English
