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Hatakeyama, Shuichi*; Ono, Masashi*; Takahashi, Hiroyuki*; Damayanthi, R. M. T.*; Otani, Chiko*; Yasumune, Takashi; Onishi, Takashi; Takasaki, Koji; Koyama, Shinichi
Journal of Low Temperature Physics, 176, p.560 - 565, 2014/01
Times Cited Count：8 Percentile：32.72(Physics, Applied)We designed and fabricated a hard X-ray and gamma-ray TES spectrometer for nuclear materials analysis. The superconducting tin absorber is coupled to an Ir/Au TES by using a gold post to improve the thermal contact between the absorber and the TES. The reported energy resolution is 156 eV FWHM at 59.5 keV and 166 eV FWHM at 122 keV gamma-rays. We performed measurement of a Pu sample and clearly separated the 
Pu (56.828 keV) and the 
Am (59.5 keV) peaks by this TES microcalorimeter which cannot be resolved by the HPGe detector.
Horikoshi, Yoshinori; Nemoto, Norio; Kurosawa, Shigeyuki*; Takasaki, Koji; Mizuniwa, Harumi
JAEA-Testing 2008-003, 29 Pages, 2008/04
JAEA-Testing-2008-003.pdf:1.65MB
In the Plutonium Fuel Technical Development Center, protective clothing suitable for sweltering radiation work was examined. Since it worried about the influence of wet protective clothing with sweat on detection of MOX powder contamination, Detection situations, the diffusion of contamination, and the osmosis and penetrability to wet protective clothing were examined about the present fabric and other new fabrics. As a result of examination, it was confirmed that the influence of detection on alpha ray in the wet condition of new fabrics was smaller than the current fabric. This report compiled the result of examination and points in the fabric selection suitable for protective clothing.
Takasaki, Koji; Sagawa, Naoki; Kurosawa, Shigeyuki*; Shioya, Satoshi; Suzuki, Kazunori; Horikoshi, Yoshinori; Mizuniwa, Harumi
JAEA-Technology 2008-028, 73 Pages, 2008/03
JAEA-Technology-2008-028.pdf:5.88MB
Recently, an imaging plate (IP) was developed. Pu analysis by an IP was studied in the JAEA Cooperative Research Scheme on the Nuclear Fuel Cycle, and the availability about detection of Pu and discrimination with radon progenies was shown. In order to apply these results to the radiation control, this research aims at evaluation of radioactivity, discrimination with radon progenies, and evaluation of AMAD by an IP. In the conventional autoradiography (ARG) by a ZnS and Polaroid film, Contamination of Pu can only be grasped by viewing. Since the digital data of the radiation and location is obtained by an IP, Pu can be detected quantitatively and radioactivity can be evaluated. As a result of this research, the image of alpha emitter on an IP is the same as that of the conventional ARG, and can be applied also to the ARG of beta and 
emitter. In measurement of Pu, the function of Image J (image-analysis software) was very available. Pu radioactivity was evaluated by an IP.
Kurihara, Osamu; Hato, Shinji; Kanai, Katsuta; Takada, Chie; Takasaki, Koji; Ito, Kimio; Ikeda, Hiroshi*; Oeda, Mikihiro*; Kurosawa, Naohiro*; Fukutsu, Kumiko*; et al.
Journal of Nuclear Science and Technology, 44(10), p.1337 - 1346, 2007/10
Times Cited Count：2 Percentile：17.95(Nuclear Science & Technology)In the case of internal contamination of radionuclides, it is necessary to perform internal dose assessment for radiation protection. For this purpose, the ICRP has given the dose coefficients and the retention and excretion rates for various radionuclides. However, these dosimetric quantities are calculated only in typical conditions, therefore, are not necessarily covered enough in the case of dose assessment in which specific information on the incident or/and individual biokinetic characteristics should be taken into account retrospectively. This paper describes a developed PC-based package of software REIDAC to meet the needs in retrospective dose assessment. REIDAC was verified by comparisons with dosimetric quantities given on the ICRP publications and several examples of practical use were also shown.
Morishita, Takatoshi; Asano, Hiroyuki; Ito, Takashi; Ueno, Akira; Hasegawa, Kazuo; Naito, Fujio*; Takasaki, Eiichi*; Tanaka, Hirokazu*; Yoshino, Kazuo*; Ikegami, Masanori*
Proceedings of 2007 Particle Accelerator Conference (PAC '07) (Internet), p.1523 - 1525, 2007/06
J-PARC linear accelerator components have been installed. The required alignment accuracy in the J-PARC linac is 0.1mm in transverse direction. In the DTL/SDTL section, the fine alignment was carried out by using an optical alignment telescope along with the cavity installation. The displacement of the DTL by the unit tank connection was monitored by a laser tracker to obtain the tolerable displacement between unit tanks. The heights of cavities and magnets were compensated form the unequal ground movement of the linac tunnel. Finally, all the cavities and magnets are aligned within the tolerable alignment error.
Ito, Takashi; Asano, Hiroyuki; Morishita, Takatoshi; Yamazaki, Yoshishige; Naito, Fujio*; Takasaki, Eiichi*; Yoshino, Kazuo*; Tanaka, Hirokazu*; Kato, Takao*; Kabeya, Zenzaburo*; et al.
Proceedings of 23rd International Linear Accelerator Conference (LINAC 2006) (CD-ROM), p.782 - 784, 2007/00
Three DTL tanks and 32 SDTL tanks for the Japan Proton Accelerator Research Complex (J-PARC) were assembled at KEK site. After the assembling, the high-power conditioning of the DTL1 and 12 SDTL tanks and the beam acceleration test for the DTL1 ware carried out. And then all the DTL and SDTL tanks have to be transported form KEK to JAEA. In order to confirm the effect of the transportation to the drift tube alignment, we measured the displacement of the drift tube positions before and after the transportation by using a prototype cavity. As a result of the test, the measured displacement of the drift tubes by the transportation was less than 0.02mm which is consistent in the measurement accuracy. Based on this result, all the DTL and SDTL tanks were transported form KEK to JAEA.
Morishita, Takatoshi; Asano, Hiroyuki; Ito, Takashi; Ikegami, Masanori*; Takasaki, Eiichi*; Tanaka, Hirokazu*; Naito, Fujio*; Yoshino, Kazuo*
Proceedings of 3rd Annual Meeting of Particle Accelerator Society of Japan and 31st Linear Accelerator Meeting in Japan (CD-ROM), p.376 - 378, 2006/00
In the J-PARC Linac, the DTL and the SDTL have been installed. A precise alignment of accelerator components is essential for high quality beam acceleration. Due to the heavy wiring for DTQs, the realignment of DTL cavity requires a long term. Then the DTL/SDTL and the focusing magnets are aligned precisely enough for the beam operation at the installation. The DTL/SDTL alignment accuracy satisfied the requirement, which confirmed by the laser tracker measurement. The floor level of the accelerator tunnel has been measured periodically. The long term motion of accelerator tunnel is quantitatively evaluated since Feb. 2005.
Ito, Takashi; Asano, Hiroyuki*; Morishita, Takatoshi; Kato, Takao*; Takasaki, Eiichi*; Tanaka, Hirokazu*; Yoshino, Kazuo*; Naito, Fujio*
Proceedings of 2nd Annual Meeting of Particle Accelerator Society of Japan and 30th Linear Accelerator Meeting in Japan, p.242 - 244, 2005/07
The third Drift Tube Linac (DTL3) is adopted for 37MeV-50MeV part of high intensity proton linac for Japan Proton Accelerator Research Complex(J-PARC). DTL3 consists of 26 full drift tubes, 2 half drift tubes and 26 post-couplers. As a result of tuning of the accelerating field of the DTL3, the resonant frequency was adjusted to 324MHz and the average accelerating field distribution was adjusted within 1%.
Morishita, Takatoshi; Ao, Hiroyuki; Ito, Takashi; Ueno, Akira; Hasegawa, Kazuo; Ikegami, Masanori*; Kubota, Chikashi*; Takasaki, Eiichi*; Tanaka, Hirokazu*; Naito, Fujio*; et al.
Proceedings of 2nd Annual Meeting of Particle Accelerator Society of Japan and 30th Linear Accelerator Meeting in Japan, p.266 - 268, 2005/07
J-PARC linear accelerator components are now being installed in the accelerator tunnel. Markings are placed on the floor, which act as a reference for the initial alignment at the installation. A planned and ongoing alignment schemes for the installation of linac components and watching the long term motion of the building are described.
Morishita, Takatoshi; Ao, Hiroyuki; Ito, Takashi; Ueno, Akira; Hasegawa, Kazuo; Ikegami, Masanori*; Kubota, Chikashi*; Naito, Fujio*; Takasaki, Eiichi*; Tanaka, Hirokazu*; et al.
Proceedings of 2005 Particle Accelerator Conference (PAC '05) (CD-ROM), p.2851 - 2853, 2005/00
In J-PARC linac, a precise alignment of accelerator components is essential for high quality beam acceleration. Markings have been placed on the floor, which act as a reference for the initial alignment at the installation. For a straight line alignment, the wire position sensor is placed on the offset position with respect to the beam center by a target holder. The hydrostatic levering system is used for watching the floor elevation over the long period.
Morishita, Takatoshi; Ao, Hiroyuki; Ito, Takashi; Ueno, Akira; Hasegawa, Kazuo; Ikegami, Masanori*; Kubota, Chikashi*; Takasaki, Eiichi*; Tanaka, Hirokazu*; Naito, Fujio*; et al.
Proceedings of 1st Annual Meeting of Particle Accelerator Society of Japan and 29th Linear Accelerator Meeting in Japan, p.671 - 673, 2004/08
A precise alignment of accelerator components is essential for the J-PARC linear accelerator. The wire position sensor is applied to measure the accelerator component positioning and the ground motion of the building is measured by the hydrostatic leveling sensors. In this paper, the scheme of the alignment system is presented.
Kondo, Yasuhiro; Akikawa, Hisashi; Anami, Shozo*; Asano, Hiroyuki*; Fukui, Yuji*; Igarashi, Zenei*; Ikegami, Kiyoshi*; Ikegami, Masanori*; Ito, Takashi; Kawamura, Masato*; et al.
Proceedings of 1st Annual Meeting of Particle Accelerator Society of Japan and 29th Linear Accelerator Meeting in Japan, p.156 - 158, 2004/08
A commissioning of the J-PARC linac DTL1 is now under way at KEK. A 30mA H
beam was accelerated to 19.7-MeV, and 100% transmission was obtained with a 20-msec-pulse-width and 12.5-Hz-repetition beam. In this paper, present status of the DTL1 commissioning and preliminary results of the commissioning, such as emittance measurements, are presented.
Kurihara, Osamu; Takasaki, Koji; Momose, Takumaro; Terakado, Yoshinori*; Takahashi, Koji*
Journal of Nuclear Science and Technology, 41(Suppl.4), p.243 - 246, 2004/03
None
Kurihara, Osamu; Takasaki, Koji; Momose, Takumaro; Terakado, Yoshinori*; Takahashi, Koji*
IRPA-11, 0 Pages, 2004/00
As an alternative to the phantom used for calibrating whole-body counters, in this study the Monte Carlo simulation was used to evaluate peak efficiencies for a whole-body counter installed at the JNC, to examine the validity of using the simulation technique to calibrate the whole-body counter. Prior to simulating a phantom, the sensitive region of the crystal in the Ge detectors which are used with the whole-body counter, was evaluated by assuming dead layers in the simulation. The phantom was then simulated based on the determined configuration of the sensitive region. As a result, the calculated peak efficiencies were fairly consistent with the measured ones. For an entire body scanning measurement, the discrepancy between the measurement and the simulation was within 4% for peak energies ranging from 81.0 keV to 1460.8 keV. The simulation technique is therefore both effective and practical for situations that are difficult to be simulated by a phantom.
Shinohara, Kunihiko; Asano, Tomohiro; Momose, Takumaro; Takeishi, Minoru; Kobayashi, Hirohide; Oka, Tsutomu; Takasaki, Koji
JNC TN8440 2003-020, 125 Pages, 2003/09
JNC-TN8440-2003-020.pdf:11.14MB
This annual report summarizes the activities of the Radiation Protection Division at JNC Tokai Works in fiscal 2002.The Tokai Works undertakes various research and development for the reprocessing of spent fuel, plutonium fuel fabrication, fast reactor fuel recycling technology, and radioactive waste treatment and disposal, all of which are done under strict safety management.The major radiation facilities in the Tokai Works are the Tokai Reprocessing Plant (TRP), which has been in operation since 1977, three MOX fuel fabrication facilities, the first of which has been in operation since 1965, the Chemical Processing Facility (CPF) where fast reactor (FR) reprocessing technologies are being developed, and various other radioisotope and uranium research laboratories.The Radiation Protection Division is responsible for radiation control in and around these facilities, including personnel monitoring, workplace monitoring, consultation on radiological work planning and evaluation, monitoring of gas and liquid waste effluents, environmental monitoring, instrumentation, calibration, quality assurance, and safety research. The Division also provides technical support and cooperation to other international and domestic institutes in the radiation protection field.In fiscal 2002, the results of radiological monitoring showed the situation to be normal, and no radiological incident or accident occurred. The maximum annual effective dose to radiation workers was 6.5 mSv and the mean annual effective dose was 0.1 mSv. Individual doses were kept within the annual dose limit specified in the safety regulations. The estimated effective dose caused by gas and liquid effluents from the TRP to members of the public around the Tokai Works was 4.2 * 10
mSv. Environmental monitoring and effluent control were performed appropriately in compliance with safety regulation and standards.
Takasaki, Koji; Kurihara, Osamu; Tasaki, Takashi; Momose, Takumaro; Maruo, Yoshihiro; Shinohara, Kunihiko
THE 47TH ANNUAL CONFERENCE ON BIOASSAY,ANALYTICAL & ENVIRONMENTAL RADIOCHEMISTRY, 0 Pages, 2002/00
None
-rays using a TES microcalorimeter with a thick Sn absorber; Spectrum analysis with Monte Carlo simulationYasumune, Takashi; Takasaki, Koji; Onishi, Takashi; Koyama, Shinichi; Hatakeyama, Shuichi*; Ono, Masashi*; Takahashi, Hiroyuki*
no journal, ,
Superconducting transition edge sensors (TES) have been developed for identification of plutonium and minor actinides. We have developed TES with a thick Sn absorber to detect X-rays and -rays. Energy dispersive spectroscopy measurements of an actinide source were conducted by the TES with a Sn absorber to demonstrate the potential for hard X-ray and -ray detection. We also performed a Monte Carlo simulation using EGS5 code in order to analyze the obtained results.
Takasaki, Shin*; Tanaka, Takahiro*; Nabemoto, Toyonobu*; Kawamura, Wataru*; Hatori, Masanori*; Suzuki, Itaru*; Okumura, Keisuke; Toh, Yosuke; Nagatani, Taketeru
no journal, ,
no abstracts in English
Kato, Yoshinari; Hashimoto, Makoto; Miyauchi, Hideaki; Yasumune, Takashi; Maeda, Eita; Takasaki, Koji; Yoshizawa, Michio; Momose, Takumaro
no journal, ,
no abstracts in English
Yasumune, Takashi; Kato, Yoshinari; Maeda, Eita; Miyauchi, Hideaki; Hashimoto, Makoto; Takasaki, Koji
no journal, ,
no abstracts in English
