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storage phosphors to wide-range neutron detectionSakasai, Kaoru; To, Kentaro; Nakamura, Tatsuya; Takakura, Kosuke; Konno, Chikara; Iwamoto, Yosuke
Proceedings of 2013 IEEE Nuclear Science Symposium and Medical Imaging Conference (2013 NSS/MIC), Vol.3, p.2024 - 2030, 2013/00
Storage characteristics of KCl:Eu phosphor were investigated in order to apply the phosphor to wide-range neutron detection. For detection of both slow and fast neutrons, 
LiF powders and polyethylene powders were added to the phosphor at the same time. The optimization of the phosphor for maximum photostimulated luminescence yields have been performed and obtained at a polyethylene weight ratio of about 0.05 when the mixtures were irradiated by fast neutron with energy of 14.8 MeV, where the weight ratio of KCl:Eu phosphor to LiF powders was fixed to be two to three. These experimental results well agreed with theoretical predictions by Monte Carlo simulation using PHITS code. The energy deposition by slow or intermediate neutrons was mainly due to charged particles as a result of nuclear reaction of Li(n,
)T. According to relativistic calculation, the energy of alpha particles or tritons cannot be uniquely determined in a laboratory system but has a certain distribution even if incident neutron energy is fixed when neutron energy is high. The calculation showed that charged particles produced by nuclear reactions such as 
K(n,) or 
Cl(n,), in addition to protons by 
H(n,n) H reaction, will contribute the total energy deposition at high energy of incident neutrons.
phosphors with radiators by irradiation of fast neutronsSakasai, Kaoru; Iwamoto, Yosuke; To, Kentaro; Nakamura, Tatsuya; Takakura, Kosuke; Konno, Chikara
2010 IEEE Nuclear Science Symposium Conference Record (CD-ROM), p.966 - 970, 2010/10
Storage characteristics of KBr:Eu phosphor were investigated when the phosphor was irradiated by fast neutron with energy of 14.8 MeV. To improve the fast neutron sensitivity, polyethylene (PE) sheets as a proton generator were set in front of the phosphors. The maximum photostimulated luminescence (PSL) yields were obtained at a PE thickness of about 3 mm. These experimental results well agreed with those by Monte Carlo simulation using PHITS code. Estimated PSL yields by 
-ray associated with fast neutron fields were negligible. This combination use of such phosphors and PE sheets will be usable for fast neutron monitoring or imaging.
phosphors with radiators by irradiation of fast neutronsSakasai, Kaoru; Iwamoto, Yosuke; Nakamura, Tatsuya; To, Kentaro; Takakura, Kosuke; Konno, Chikara
Proceedings of 2009 IEEE Nuclear Science Symposium and Medical Imaging Conference (2009 NSS/MIC), Vol.2, p.1422 - 1426, 2009/00
Times Cited Count：1 Percentile：54.1(Engineering, Electrical & Electronic)Storage phosphors such as KCl:Eu with low -ray sensitivity were applied to detection of fast neutrons using polyethylene (PE) sheets as a proton generator that were set in front of the phosphors. The maximum PSL yields were obtained at a PE thickness of 3 mm when the neutron energy was 14.8 MeV. These experimental results well agreed with those by Monte Carlo simulation using PHITS code. Estimated PSL yields by -ray associated with fast neutron fields were negligible. This combination use of such phosphors and PE sheets will be usable for fast neutron monitoring or imaging in a high -ray fields.
de Boissieu, M.*; Francoual, S.*; Minalkovi
, M.*; Shibata, Kaoru; Baron, A. Q. R.*; Sidis, Y.*; Ishimasa, Tsutomu*; Wu, D.*; Lograsso, T.*; Regnault, L.-P.*; et al.
Nature Materials, 6(12), p.977 - 984, 2007/12
Times Cited Count：42 Percentile：81.31(Chemistry, Physical)We have carried out inelastic X-ray and neutron scattering experiments on single-grain samples of the Zn-Mg-Sc icosahedral quasicrystal and of the Zn-Sc periodic cubic 1/1 approximant, with the aim of studying the respective influence of the local order and the long-range order (periodic or quasiperiodic) on lattice dynamics. Besides the overall similarities and the existence of a pseudo-gap in the transverse dispersion relation, marked difference are observed, the pseudo-gap being larger and better defined in the approximant than in the quasicrystal. These results are compared with simulations on atomic models and using oscillating pair potentials, and the simulations reproduce in detail the experimental results.
Kanasugi, Yuichi*; Hamada, Nobuyuki*; Wada, Seiichi*; Funayama, Tomoo; Sakashita, Tetsuya; Kakizaki, Takehiko; Kobayashi, Yasuhiko; Takakura, Kaoru*
International Journal of Radiation Biology, 83(2), p.73 - 80, 2007/02
Times Cited Count：31 Percentile：87.87(Biology)no abstracts in English
Takakura, Kaoru*; Kanasugi, Yuichi*; Hamada, Nobuyuki*; Wada, Seiichi*; Funayama, Tomoo; Sakashita, Tetsuya; Kakizaki, Takehiko; Kobayashi, Yasuhiko
JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 112, 2007/02
no abstracts in English
Yokoya, Akinari; Takakura, Kaoru*; Watanabe, Ritsuko; Akamatsu, Ken*; Ito, Takashi*
Radiation Research, 162(4), p.469 - 473, 2004/10
Radicals induced in a single crystal of 5-bromouracil (BrUra) by synchrotron soft X-rays in the Br K-edge region (13.461-13482 keV) were investigated using the X-band EPR method. The crystal was irradiated at three peak energies in the absorption spectrum at room temperature or at 80K. A hydrogen abstraction radical derived from N1 atom of the pyrimidine ring was commonly observed for all of the energies used, though with some variation in quantity. Similar characteristics were also observed in the EPR signal for the off-K-edge low energy (13.42 keV) and when 
Co -ray irradiation was employed as the reference. When irradiated at 80K, a much larger exposure (roughly 10 times) of soft X-rays was needed to obtain the same signal intensity as that observed at room temperature. EPR signals were not detectable with g-irradiation at liquid nitrogen temperature.
Yokoya, Akinari; Takakura, Kaoru*; Watanabe, Ritsuko; Akamatsu, Ken*; Ito, Takashi*
Radiation Research, 162(4), p.469 - 473, 2004/10
Times Cited Count：3 Percentile：10.08(Biology)X-ray absorption spectra from single crystals of 5-Bromouracil were measured with the transmission mode in the energy range from 13.41 to 13.50 keV using the linearly polarized synchrotron radiation (SR). A characteristic resonance structure, consisting of four peaks, was recognized in the spectra in the Br K-edge region. The intensities of these peaks were strongly dependent on the crystal rotation about the normal of the crystal b-c plane, which was set perpendicular to the X-ray beam direction. (SR X-rays are polarized in the horizontal plane.) Molecular orbital calculations indicate that these resonance peaks are associated with the transitions from the 1s electron of Br to the Br-C molecular antibonding orbitals and to a shape resonance. The observed anisotropy of each photoabsorption peak might originate from the angular dependences of these molecular orbitals.
Aotani, Hideaki*; Funayama, Tomoo; Wada, Seiichi*; Sakashita, Tetsuya; Kobayashi, Yasuhiko; Hasan, K.*; Kaul, S.*; Takakura, Kaoru*
no journal, ,
no abstracts in English
Kanasugi, Yuichi*; Funayama, Tomoo; Wada, Seiichi*; Sakashita, Tetsuya; Kobayashi, Yasuhiko; Takakura, Kaoru*
no journal, ,
no abstracts in English
Takakura, Kaoru*; Kanasugi, Yuichi*; Hamada, Nobuyuki*; Wada, Seiichi*; Kobayashi, Yasuhiko; Funayama, Tomoo; Sakashita, Tetsuya; Kakizaki, Takehiko
no journal, ,
no abstracts in English
Takakura, Kaoru*; Kanasugi, Yuichi*; Hamada, Nobuyuki*; Wada, Seiichi*; Funayama, Tomoo; Sakashita, Tetsuya; Kakizaki, Takehiko; Kobayashi, Yasuhiko
no journal, ,
no abstracts in English
Hamada, Nobuyuki*; Ni, M.; Kanasugi, Yuichi*; Iwakawa, Mayumi*; Imadome, Kaori*; Funayama, Tomoo; Sakashita, Tetsuya; Sora, Sakura*; Imai, Takashi*; Takakura, Kaoru*; et al.
no journal, ,
Hamada, Nobuyuki*; Iwakawa, Mayumi*; Imadome, Kaori*; Kanasugi, Yuichi*; Funayama, Tomoo; Sakashita, Tetsuya; Takakura, Kaoru*; Imai, Takashi*; Kobayashi, Yasuhiko
no journal, ,
no abstracts in English
Hamada, Nobuyuki*; Iwakawa, Mayumi*; Kanasugi, Yuichi*; Imadome, Kaori*; Funayama, Tomoo; Sakashita, Tetsuya; Takakura, Kaoru*; Imai, Takashi*; Kobayashi, Yasuhiko
no journal, ,
no abstracts in English
Watanabe, Jun*; Fukumoto, Masakatsu*; Otsuka, Yusuke*; Ueda, Yoshio*; Arai, Takashi; Asakura, Nobuyuki; Nakano, Tomohide; Sato, Masayasu; Yagyu, Junichi; Ochiai, Kentaro; et al.
no journal, ,
no abstracts in English
-polyethrene phosphors by irradiation of fast neutronsSakasai, Kaoru; To, Kentaro; Nakamura, Tatsuya; Takakura, Kosuke; Konno, Chikara; Iwamoto, Yosuke
no journal, ,
no abstracts in English
storage phosphor to wide-range neutron detectionSakasai, Kaoru; To, Kentaro; Nakamura, Tatsuya; Takakura, Kosuke; Konno, Chikara; Iwamoto, Yosuke
no journal, ,
no abstracts in English
