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Maehata, Keisuke*; Maeda, Makoto; Iyomoto, Naoko*; Ishibashi, Kenji*; Nakamura, Keisuke; Aoki, Katsunori; Takasaki, Koji; Mitsuda, Kazuhisa*; Tanaka, Keiichi*
IEICE Transactions on Electronics (Internet), E98-C(3), p.178 - 185, 2015/03
Times Cited Count：1 Percentile：7.63(Engineering, Electrical & Electronic)A four-pixel-array superconducting transition-edge sensor (TES) microcalorimeter with a mushroom-shaped absorber was fabricated for the energy dispersive spectroscopy performed on a transmission electron microscope. The TES consists of a bilayer of Au/Ti with either a 120-nm or 50-nm thickness. The absorber of 5.0 
m thick is made from a Au layer and its stem is deposited in the center of the TES surface. A Ta
O
insulating layer of 100-nm thickness is inserted between the overhang region of the absorber and the TES surface. A selected pixel of the TES microcalorimeter was operated for the detection of L X rays emitted from an 
Am source. A response of the TES microcalorimeter to L X rays was obtained by analyzing detection signal pulses with using the optimal filter method. An energy resolution was obtained to be 33 eV of the full width at half maximum value at 17.751 keV. Response to L X rays emitted from a mixture source of 
Pu, 
Pu and Am was obtained by operating the selected pixel of the TES microcalorimeter Major L X-ray peaks of progeny elements of decay of Pu and Am isotopes were clearly identified in the obtained energy spectrum. The experimental results demonstrated the separation of Am and plutonium isotopes by L X-ray spectroscopy.
Endo, Satoru*; Tanaka, Kenichi*; Takada, Masashi*; Onizuka, Yoshihiko*; Miyahara, Nobuyuki*; Sato, Tatsuhiko; Ishikawa, Masayoshi*; Maeda, Naoko*; Hayabuchi, Naofumi*; Shizuma, Kiyoshi*; et al.
Medical Physics, 34(9), p.3571 - 3578, 2007/09
Times Cited Count：7 Percentile：24.82(Radiology, Nuclear Medicine & Medical Imaging)Absorbed doses from main charged particle beams and charged-particle fragments have been measured with high accuracy for particle therapy but there are few reports for doses from neutron components produced as fragments. This study describes measurements on neutron dose produced by carbon beam, microdosimetric distributions of secondary neutrons produced by 290 MeV/nucleon carbon beams have been measured by using a tissue equivalent proportional counter (TEPC) at the Heavy Ion Medical Accelerator in Chiba (HIMAC) at the National Institute of Radiological Sciences (NIRS). The ratios of neutrons to charged particle fragments dominated to be 11 to 89 % in the absorbed doses at the side and below the faces of the acrylic phantom (300 mm height 
300 mm width 253 mm thickness).
Nakamura, Keisuke; Maeda, Makoto*; Aoki, Katsunori; Yasumune, Takashi; Takasaki, Koji; Maehata, Keisuke*; Iyomoto, Naoko*; Ishibashi, Kenji*; Mitsuda, Kazuhisa*; Tanaka, Keiichi*
no journal, ,
no abstracts in English
Nakamura, Keisuke; Maeda, Makoto; Morishita, Yuki; Takasaki, Koji; Maehata, Keisuke*; Iyomoto, Naoko*; Ishibashi, Kenji*; Mitsuda, Kazuhisa*
no journal, ,
no abstracts in English
Maeda, Makoto*; Maehata, Keisuke*; Iyomoto, Naoko*; Ishibashi, Kenji*; Takasaki, Koji; Nakamura, Keisuke; Aoki, Katsunori; Mitsuda, Kazuhisa*; Tanaka, Keiichi*
no journal, ,
no abstracts in English
Nakamura, Keisuke; Aoki, Katsunori; Takasaki, Koji; Maeda, Makoto*; Maehata, Keisuke*; Iyomoto, Naoko*; Ishibashi, Kenji*; Mitsuda, Kazuhisa*; Tanaka, Keiichi*
no journal, ,
no abstracts in English
Nakamura, Keisuke; Maeda, Makoto; Maehata, Keisuke*; Iyomoto, Naoko*; Ishibashi, Kenji*; Takasaki, Koji; Mitsuda, Kazuhisa*
no journal, ,
A transition-edge-sensor (TES) microcalorimeter has been developed for measurement of X-rays and 
-rays with ultra-high energy resolution. In this work, we developed a four-pixel TES microcalorimeter to measure L X-rays emitted by transuranium elements. Each TES was composed of bilayer film of a 120-nm-thick Au layer and a 50-nm-thick Ti layer, and the transition temperature was approximately 130 mK. An absorber deposited on each Au-Ti bilayer was a 5-m-thick layer of Au to achieve an absorption efficiency of 35-80% for the energy range of L X-rays (10-30 keV). The developed four pixel TES microcalorimeter was irradiated with L X-rays emitted form Pu-238, Pu-239, and Am-241 sources. As the result, we obtained an L X-ray energy spectrum with high energy resolution of 
40 eV (full width at half maximum) for an L X-ray of 17.75 keV.
