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Yamaguchi, Mitsutaka; Kawachi, Naoki; Kamiya, Tomihiro; Sato, Takahiro; Suzui, Nobuo; Fujimaki, Shu; Odaka, Hirokazu*; Ishikawa, Shinnosuke*; Kokubun, Motohide*; Watanabe, Shin*; et al.
JAEA-Review 2011-043, JAEA Takasaki Annual Report 2010, P. 145, 2012/01
no abstracts in English
Yamaguchi, Mitsutaka; Kawachi, Naoki; Suzui, Nobuo; Fujimaki, Shu; Kamiya, Tomihiro; Odaka, Hirokazu*; Ishikawa, Shinnosuke*; Kokubun, Motohide*; Watanabe, Shin*; Takahashi, Tadayuki*; et al.
Nuclear Instruments and Methods in Physics Research A, 648(Suppl.1), p.S2 - S7, 2011/08
Times Cited Count:2 Percentile:19.86(Instruments & Instrumentation)We are constructing a three-dimensional imaging system for medical and biological applications. The system will allow simultaneous imaging at high spatial and energy resolutions across a wide energy range, from several tens of keV to a few MeV. In this work, one prototype head module have been developed for a multi-head Si/CdTe Compton camera system. The performance of the prototype was evaluated with a sealed Ba-133 radiation source. The experiments confirmed that the imaging results were consistent with actual source position. In addition to the resolution for the parallel directions to the detector surface, the position resolution was evaluated for the depth direction at a point in near region of the head-module. These position resolutions were well reproduced by Monte Carlo simulation results.
Yamaguchi, Mitsutaka; Kawachi, Naoki; Kamiya, Tomihiro; Suzui, Nobuo; Fujimaki, Shu; Odaka, Hirokazu*; Ishikawa, Shinnosuke*; Kokubun, Motohide*; Watanabe, Shin*; Takahashi, Tadayuki*; et al.
2010 IEEE Nuclear Science Symposium Conference Record (CD-ROM), p.2004 - 2007, 2010/10
Nakashima, Hiroshi; Nakane, Yoshihiro; Masukawa, Fumihiro; Matsuda, Norihiro; Oguri, Tomomi*; Nakano, Hideo*; Sasamoto, Nobuo*; Shibata, Tokushi*; Suzuki, Takenori*; Miura, Taichi*; et al.
Radiation Protection Dosimetry, 115(1-4), p.564 - 568, 2005/12
Times Cited Count:8 Percentile:49.16(Environmental Sciences)The High Intensity Proton Accelerator Project, named as J-PARC, is in progress, aiming at studies on the latest basic science and the advancing nuclear technology. In the project, the high-energy proton accelerator complex of the world highest intensity is under construction. In order to establish a reasonable shielding design, both simplified and detailed design methods were used in the shielding design of J-PARC. This paper reviews the present status of the radiation safety design study for J-PARC.
Nakano, Hideo*; Masukawa, Fumihiro; Nakashima, Hiroshi; Sasamoto, Nobuo*; Tayama, Ryuichi*; Handa, Hiroyuki*; Hayashi, Katsumi*
Journal of Nuclear Science and Technology, 41(Suppl.4), p.50 - 53, 2004/03
In order to estimate accuracy of the various calculation methods for the neutron streaming through a maze and duct in proton accelerator facilities, we performed benchmark analyses by using the radiation shielding design codes. According to the results of the benchmark analyses, it is concluded that NMTC/MCNP, MCNPX and DUCT-III are applicable to actual calculation of the duct-streaming radiations for J-PARC.
Masukawa, Fumihiro; Nakano, Hideo*; Nakashima, Hiroshi; Sasamoto, Nobuo; Tayama, Ryuichi*; Hayashi, Katsumi*; Shin, Kazuo*
Journal of Nuclear Science and Technology, 41(Suppl.4), p.46 - 49, 2004/03
A simple design code for duct-streaming radiations, DUCT-III was applied to the analyses of the streamed neutron spectra measured at TIARA labyrinth with two bends. The code satisfactorily reproduced the measured neutron energy spectra and the Monte Carlo calculations, except that every calculation overestimated the measured thermal components by factor of 2 or 3.
Masukawa, Fumihiro; Nakano, Hideo*; Nakashima, Hiroshi; Sasamoto, Nobuo; Tayama, Ryuichi*; Handa, Hiroyuki*; Hayashi, Katsumi*; Hirayama, Hideo*; Shin, Kazuo*
JAERI-Tech 2003-018, 42 Pages, 2003/03
no abstracts in English
Masukawa, Fumihiro; Nakashima, Hiroshi; Sasamoto, Nobuo; Nakano, Hideo*; Tayama, Ryuichi*
Journal of Nuclear Science and Technology, 39(Suppl.2), p.1268 - 1271, 2002/08
no abstracts in English
Yokoyama, Hiroomi*; Kanazawa, Toshio*; Fukuma, Tadashi*; Tamekiyo, Kozo*; Yanagida, Koji*; Furuya, Takashi*; Kono, Hiroshi*; Ito, Keiji*; Shirakura, Takao*; Kashiwara, Shinichiro*; et al.
PNC TN8410 87-086VOL2, 944 Pages, 1986/09
Yokoyama, Hiroomi*; Kanazawa, Toshio*; Fukuma, Tadashi*; Tamekiyo, Kozo*; Yanagida, Koji*; Furuya, Takashi*; Kono, Hiroshi*; Ito, Keiji*; Shirakura, Takao*; Kashiwara, Shinichiro*; et al.
PNC TN8410 87-086VOL1, 1037 Pages, 1986/09
A detailed design for a New Material Nitric Acid Recovery Evaporator was carried out with a plan to use it to replace an already constructed stainless steel Nitric Acid Recovery Evaporator at the Power Reactor and Nuclear Fuel Development Corporation's Tokai Works. Most of the original Evaporator's conditions such as compliance with applicable laws, standards, structure, treatment performance and operating conditions were maintained when designing the new machine. The material is titanium with the addition of 5% tantalum. The Evaporator was designed with an operational life expectance of 10 years. We have calculated that the new Evaporator will have sufficient strength (including a seismatic design) and have the same evaporative performance as the already constructed one. During design, we referred to the results of already completed basic designs (Phase 1) of New Material Nitric Acid Recovery Evaporators, design and production of small-scale test equipment units, and the development of successful joints between different materials. We also considered manufacturing, installation, trial runs, maintenance, and the specifications for materials used for manufacturing, installation, piping and operation of the new Evaporator.
Kawachi, Naoki; Fujimaki, Shu; Suzui, Nobuo; Ishii, Satomi; Ishioka, Noriko; Matsuhashi, Shimpei; Sato, Takahiro; Watanabe, Shin*; Takeda, Shinichiro*; Takahashi, Tadayuki*; et al.
no journal, ,
Kawachi, Naoki; Fujimaki, Shu; Suzui, Nobuo; Ishii, Satomi; Ishioka, Noriko; Matsuhashi, Shimpei; Sato, Takahiro; Watanabe, Shin*; Takeda, Shinichiro*; Takahashi, Tadayuki*; et al.
no journal, ,
no abstracts in English
Kawachi, Naoki; Suzui, Nobuo; Ishii, Satomi; Ito, Sayuri; Watanabe, Shigeki; Ishioka, Noriko; Takahashi, Tadayuki*; Nakano, Takashi*; Fujimaki, Shu
no journal, ,
no abstracts in English
Yamaguchi, Mitsutaka; Kamiya, Tomihiro; Kawachi, Naoki; Suzui, Nobuo; Fujimaki, Shu; Ishioka, Noriko; Watanabe, Shin*; Ishikawa, Shinnosuke*; Odaka, Hirokazu*; Kokubun, Motohide*; et al.
no journal, ,
We have developed a prototype of Si/CdTe medical Compton camera. To overcome low spatial resolution of one head camera, we have proposed multi-head Compton camera. In this work, we studied the spatial resolution by comparing the measured resolution with Monte Carlo simulation. The head of the Compton camera consist of two layers of Si strip detector and two layers of CdTe strip detector. Monte Carlo simulations were performed by using a camera simulator Geant4 toolkit. After the Monte Carlo simulations, imaging process using LM-ML-EM, algorithm was performed in a 3D-space. The measured result was well agree with the simulation result. The spatial resolution is about 6 mm for double-head case while the spatial resolution of depth direction is about 15 mm for single-head case. These results indicate that the spatial resolution is improved and clear 3D-image is taken by using multi-head Compton camera.
Yamaguchi, Mitsutaka; Torikai, Kota*; Shimada, Hirofumi*; Kawachi, Naoki; Kamiya, Tomihiro; Suzuki, Yoshiyuki*; Yoshida, Yukari*; Sato, Takahiro; Suzui, Nobuo; Fujimaki, Shu; et al.
no journal, ,
Measurement of the energy distribution of ray under the Carbon-Ion Beam Therapy environment was carried out in order to measure the background for positron annihilation ray peak in the use of in-beam monitoring. In this fiscal year, we studied the effect of the thermal neutron in the irradiation room against a CdTe semiconductor detector. Carbon-ion beam was irradiated on a water phantom and the energy spectrum of ray was measured. The 559 keV ray peak which is emitted from the neutron absorption reaction of Cd-133 are observed in the spectrum. For the case using the boron-paraffin block, the peak is clearly disappeared and the continuous component of the spectrum under the 511 keV annihilation peak decreased and the S/N ratio was refined. Neutron damage of the detector was not observed after the 20 hours use in the 108 pps beam environment.
Yamaguchi, Mitsutaka; Kamiya, Tomihiro; Kawachi, Naoki; Suzui, Nobuo; Fujimaki, Shu; Odaka, Hirokazu*; Ishikawa, Shinnosuke*; Kokubun, Motohide*; Watanabe, Shin*; Takahashi, Tadayuki*; et al.
no journal, ,
We are constructing a three-dimensional imaging system for medical and biological applications as a device that can provide simultaneous imaging, having high spatial and energy resolutions and wide energy range from several tens keV to a few MeV, by diverting the most advanced space-observation technology, Si/CdTe semiconductor Compton camera, developed in ISAS/JAXA. The Si/CdTe Compton camera was developed under the assumption that the use of moderate temperature and the Analog ASIC for signal processing. Moreover, because the solid and thin scattering layer allows close placement of the measured object, good angular resolution corresponds to good spatial resolution directly. These aspects allow construction of compact medical system. In contrast to space-observation use, three-dimensional imaging ability becomes important for life science research. In order to achieve a good three-dimensional spatial resolution, modularizing the Compton camera into a small camera head and allowing multi-angle imaging with multi-head structure is required. In this work, a head module has been developed as a prototype module of the multi-head system. Sensor and circuit modules are closely arranged and put in a compact vacuum-insulating cylindrical housing. Each of camera heads will be fixed on robot arms and be able to adjust the positions and the directions. Performance evaluation test was made for the prototype module with a sealed Ba-133 radiation source. We confirmed that the imaging result is consistent with the source positioning. The angular resolution measure, abbreviated as ARM, was estimated to be 4.5 degree. The result of the test was compared with a Monte Carlo simulation study. We will report the details of the prototype module and the result of the performance evaluation test. The expecting three-dimensional performance will also be reported.
Yamaguchi, Mitsutaka; Kamiya, Tomihiro; Kawachi, Naoki; Suzui, Nobuo; Ishioka, Noriko; Fujimaki, Shu; Watanabe, Shin*; Ishikawa, Shinnosuke*; Odaka, Hirokazu*; Kokubun, Motohide*; et al.
no journal, ,
no abstracts in English
Yamaguchi, Mitsutaka; Kawachi, Naoki; Suzui, Nobuo; Fujimaki, Shu; Kamiya, Tomihiro; Odaka, Hirokazu*; Ishikawa, Shinnosuke*; Kokubun, Motohide*; Watanabe, Shin*; Takahashi, Tadayuki*; et al.
no journal, ,
no abstracts in English
Yamaguchi, Mitsutaka; Kawachi, Naoki; Suzui, Nobuo; Fujimaki, Shu; Kamiya, Tomihiro; Odaka, Hirokazu*; Kokubun, Motohide*; Takeda, Shinichiro*; Ishikawa, Shinnosuke*; Watanabe, Shin*; et al.
no journal, ,
no abstracts in English
Kawachi, Naoki; Yamaguchi, Mitsutaka; Nagao, Yuto; Suzui, Nobuo; Fujimaki, Shu; Kamiya, Tomihiro; Odaka, Hirokazu*; Kokubun, Motohide*; Takeda, Shinichiro*; Ishikawa, Shinnosuke*; et al.
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