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64 cm
area position-sensitive scintillation neutron detector as an alternative to helium-3 gas based detectorNakamura, Tatsuya; To, Kentaro; Honda, Katsunori; Ebine, Masumi; Birumachi, Atsushi; Sakasai, Kaoru
Proceedings of 2015 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC 2015), Vol.1, p.680 - 683, 2016/11
A two-dimensional scintillation neutron detector that has neutron-sensitive area of 64 64 cm was developed for neutron scattering instruments by using wavelength shifting fibers technology. We designed the detector to have a pixel size of 20 20 mm. In order to compensate light attenuation occurred travelling along the wavelength-shifting fiber the scintillation light was read out from both sides of the fiber. The prototype detector exhibited a detection efficiency of 40% for 1.8
neutrons, which was similar to previously developed detector with a smaller size of 32 32 cm. The detailed detector design and experimental results measured by using the pulsed neutrons at the J-PARC/MLF are presented.
Nakamura, Tatsuya; To, Kentaro; Sakasai, Kaoru; Honda, Katsunori; Soyama, Kazuhiko; Katagiri, Masaki*
JAEA-Conf 2015-002, p.391 - 398, 2016/02
Development of position-sensitive scintillator detectors at the J-PARC/MLF is briefly reviewed. The detector development for the neutron scattering instruments in the J-PARC/MLF initiated back in 2001. After the basic experiments and design study we have produced first beam line detectors in 2008 both with the one and two-dimensional position-sensitivity. With an extension of the fiber detector technology the detector that has an active area of 256 256 mm with a 4-mm spatial resolution was designed and made for the single crystal diffractometer, SENJU, in 2011. In the presentation recent development work including the alternative detectors to 
He gas is also introduced as well as the new detector development for the nextiBIX instrument.
LiF scintillator for detecting thermal neutronsNakamura, Tatsuya; To, Kentaro; Honda, Katsunori; Sakasai, Kaoru; Soyama, Kazuhiko; Katagiri, Masaki*
Journal of Instrumentation (Internet), 9(11), p.C11020_1 - C11020_7, 2014/11
Times Cited Count：0 Percentile：0.01(Instruments & Instrumentation)An empirical formula that predicts a spatial resolution of a thermal neutron detector comprising wavelength-shifting (WLS) fibre arrays coupled with a ZnS/LiF scintillator screen was derived based on the experimental results. The spatial resolutions of the test detectors were measured separately to evaluate the contributions due to light spread within the part of the scintillator and the part of the WLS fibres layres. The calculated results by using the derived formula reproduced the results with the test detectors, demonstrating the feasibility of the formula for designing a neutron-detecting head of this type detector.
He at J-PARC/MLFNakamura, Tatsuya; To, Kentaro; Honda, Katsunori; Birumachi, Atsushi; Ebine, Masumi; Sakasai, Kaoru; Soyama, Kazuhiko; Katagiri, Masaki*
Journal of Physics; Conference Series, 528, p.012042_1 - 012042_7, 2014/07
Times Cited Count：5 Percentile：87.86(Optics)A wavelength-shifting fiber based scintillator detector has been developed as a helium-3 alternative detector in J-PARC/MLF. The detector is aimed at using for an inelastic neutron scattering instrument in a pulsed neutron source. The detector should have a capability to have a large-area coverage with a moderate pixel size as well as high detector efficiency, low 
sensitivity, and a low background rate. We have developed a detector that has a larger neutron-sensitive area with a moderate pixel size based on the detector implemented in the SENJU instrument in the J-PARC/MLF. The prototype detector has a pixel size of 20 20 mm with a neutron-sensitive area of 320 320 mm. In the presentation detailed detector performances are presented in comparison to those measured by an original SENJU detector.
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ceramic scintillator detector as an alternative to a He-gas-based detector for a plutonium canister assay systemNakamura, Tatsuya; Ozu, Akira; To, Kentaro; Sakasai, Kaoru; Suzuki, Hiroyuki; Honda, Katsunori; Birumachi, Atsushi; Ebine, Masumi; Yamagishi, Hideshi*; Takase, Misao; et al.
Nuclear Instruments and Methods in Physics Research A, 763, p.340 - 346, 2014/05
Times Cited Count：3 Percentile：27.01(Instruments & Instrumentation)A neutron-sensitive ZnS/BO ceramic scintillator detector was developed as an alternative to a He-gas-based detector for use in a plutonium canister assay system. The detector has a modular structure, with a flat ZnS/BOceramic scintillator strip that is installed diagonally inside a light-reflecting aluminium case with a square cross section. The prototype detectors, which have a neutron-sensitive area of 30 mm 250 mm, exhibited a sensitivity of 21.7-23.4 
0.1 cps
nv for thermal neutrons, a 
Cs -ray sensitivity of 1.1-1.9 
0.2 10
and a count variation of less than 6% over the detector length. A trial experiment revealed a temperature coefficient of less than -0.24 0.05% / 
C over the temperature range of 20-50C.
He-gas-based detector for neutron-scattering instrumentsNakamura, Tatsuya; Katagiri, Masaki*; To, Kentaro; Honda, Katsunori; Suzuki, Hiroyuki; Ebine, Masumi; Birumachi, Atsushi; Sakasai, Kaoru; Soyama, Kazuhiko
Nuclear Instruments and Methods in Physics Research A, 741, p.42 - 46, 2014/03
Times Cited Count：7 Percentile：48.36(Instruments & Instrumentation)A position-sensitive tubular scintillator-based neutron detector is proposed as an alternative to a He-gas-based detector. The detector has a neutron-detecting element constructed from rolled ZnS/LiF scintillator screens that sandwich wavelength-shifting (WLS) fibre coils (SFC element). Multiple SFC elements are enclosed in an aluminium tube in a row to form a one-dimensional position-sensitive neutron detector. The design of the WLS fibre coil, which was determined by performing basic experiments, comprised two 0.75-mm-diameter WLS fibres wound in parallel at a pitch of 1.5 mm. A 64-element detector with a pixel size of 22 mm 20 mm (width length) successfully demonstrated the detection principle. The tubular shape of the new detector is similar to the usual 25-mm-diameter He tube, making this an alternative detector with the potential to be installed in a vacuum tank for inelastic-neutron-scattering instruments.
m spatial resolution comprising a fibre-optic taper with wavelength-shifting fibre readout for time-of-flight neutron imagingNakamura, Tatsuya; To, Kentaro; Kawasaki, Takuro; Honda, Katsunori; Suzuki, Hiroyuki; Ebine, Masumi; Birumachi, Atsushi; Sakasai, Kaoru; Soyama, Kazuhiko; Katagiri, Masaki*
Nuclear Instruments and Methods in Physics Research A, 737, p.176 - 183, 2014/02
Times Cited Count：13 Percentile：70.2(Instruments & Instrumentation)LiF scintillator and wavelength shifting fibers with high spatial resolution and with low gamma-ray sensitivityNakamura, Tatsuya; To, Kentaro; Kawasaki, Takuro; Honda, Katsunori; Birumachi, Atsushi; Ebine, Masumi; Sakasai, Kaoru; Soyama, Kazuhiko; Katagiri, Masaki*
Proceedings of 2014 IEEE Nuclear Science Symposium and Medical Imaging Conference; 21st International Symposium on Room-Temperature Semiconductor X-ray and -ray detectors (NSS/MIC 2014), p.1751 - 1753, 2014/00
The ZnS scintillator-based two-dimensional detector was developed for a time-of-flight neutron imaging with a high spatial resolution and a low -ray sensitivity. The detector is comprised of a thin ZnS scintillator with crossed wavelength-shifting-fibers (WLS fibers) arrays equipped with the fiber optic taper (FOT). The developed detector based on a neutron counting method has a high spatial resolution of less than 100 um (in FWHM) with a moderate count rate capability of several tens of thousands of cps. Of particular interest is its low -ray sensitivity of 10. Imaging capabilities of the detector are demonstrated by using a high-intensity pulsed neutron beam at the Materials and Life Science Experimental Facility in the Japan Proton Accelerator Complex (J-PARC/MLF).
Nakamura, Tatsuya; To, Kentaro; Kawasaki, Takuro; Honda, Katsunori; Suzuki, Hiroyuki; Ebine, Masumi; Birumachi, Atsushi; Sakasai, Kaoru; Soyama, Kazuhiko; Katagiri, Masaki*
Proceedings of 2013 IEEE Nuclear Science Symposium and Medical Imaging Conference (2013 NSS/MIC), Vol.4, p.2367 - 2369, 2013/00
The detection efficiency of a ZnS-based neutron scintillator detector was evaluated as a function of the incident angle and the wavelength of a neutron. A pulsed neutron beam that has a wavelength from 1 to 8 was incident to the test detector that implemented a ZnS/LiF and ZnS/BO scintillator that have thicknesses of 0.45 and of 0.20 mm, respectively. In each scintillator the detection efficiency increased as the incident angle increased for neutrons with a wavelength shorter than about 3. A comparison between the experimental results and the model fitting are presented.
Sn conductor and central solenoid model coils for ITERTakahashi, Yoshikazu; Ando, Toshinari; Hiyama, Tadao; Nakajima, Hideo; Kato, Takashi; Sugimoto, Makoto; Isono, Takaaki; Oshikiri, Masayuki*; Kawano, Katsumi; Koizumi, Norikiyo; et al.
Fusion Engineering and Design, 41(1-4), p.271 - 275, 1998/09
Times Cited Count：4 Percentile：38.68(Nuclear Science & Technology)no abstracts in English
Nakamura, Tatsuya; Ozu, Akira; To, Kentaro; Ebine, Masumi; Birumachi, Atsushi; Suzuki, Hiroyuki; Honda, Katsunori; Takase, Misao; Kurata, Noritaka; Haruyama, Mitsuo; et al.
no journal, ,
no abstracts in English
Birumachi, Atsushi; Ebine, Masumi; Nakamura, Tatsuya; To, Kentaro; Sakasai, Kaoru; Honda, Katsunori; Soyama, Kazuhiko; Katagiri, Masaki*
no journal, ,
no abstracts in English
Ebine, Masumi; Birumachi, Atsushi; Nakamura, Tatsuya; To, Kentaro; Sakasai, Kaoru; Honda, Katsunori; Soyama, Kazuhiko; Katagiri, Masaki*
no journal, ,
no abstracts in English
Nakamura, Tatsuya; To, Kentaro; Sakasai, Kaoru; Honda, Katsunori; Ebine, Masumi; Birumachi, Atsushi; Soyama, Kazuhiko; Katagiri, Masaki*
no journal, ,
We have initiated the development of the two-dimensional scintillator neutron detector for a protein diffractometer. The diffractometer is planned to be built in the J-PARC/MLF near future. We propose the detector designs that could fulfill the required specification for the instrument together with some basic experimental results.
Nakamura, Tatsuya; To, Kentaro; Honda, Katsunori; Ebine, Masumi; Birumachi, Atsushi; Sakasai, Kaoru; Soyama, Kazuhiko; Katagiri, Masaki*
no journal, ,
Position-sensitive scintillation neutron detectors developed for neutron scattering instruments in the Materials and Life science experimental Facility in Japan Proton Accelerator Research Complex (J-PARC/MLF) are briefly reviewed. Most of our detectors employ clear or wavelength-shifting(WLS) fibre read-out technologies coupled with the ZnS/10BO ceramic scintillator or ZnS/LiF scintillator. The detector parameters such as detection area, pixel size vary in each instrument, the detector using WLS fibres can meet such requirements with a proper design: selecting a fiber diameter, a pitch between the fibres etc. By fully exploiting this flexibility in detector design we have developed the detector that has an even larger area than SENJU detector as alternative to a He gas-based detector. In the presentation we would like to mention further possibility of the scintillator-based WLS fibre technologies and detectors to the future instruments.
Nakamura, Tatsuya; To, Kentaro; Honda, Katsunori; Ebine, Masumi; Birumachi, Atsushi; Sakasai, Kaoru; Soyama, Kazuhiko; Katagiri, Masaki*
no journal, ,
We have developed a time-of-flight neutron imager based on the two-dimensional scintillator neutron detector technology for applications in the J-PARC/MLF. The detector is comprised of a thin ZnS scintillator with crossed wavelength-shifting-fibers arrays equipped with the fiber optic taper. The developed detector based on a neutron counting method has a high spatial resolution of less than 100 um in full width at half maximum with a -ray sensitivity of less than 1010. The detector design and basic detector performances are presented.
Ebine, Masumi; Nakamura, Tatsuya; To, Kentaro; Honda, Katsunori; Birumachi, Atsushi; Sakasai, Kaoru
no journal, ,
The center of gravity method is developed for a two-dimensional scintillator neutron detector for a protein diffractometer in the J-PARC/MLF. Details of the FPGA-based digital signal processing circuit and the detector performances are presented.
Nakamura, Tatsuya; To, Kentaro; Honda, Katsunori; Ebine, Masumi; Birumachi, Atsushi; Sakasai, Kaoru
no journal, ,
We have developed a two-dimensional scintation detector for the protein-dedicated neutron diffractometer to be constructed in J-PARC/MLF. The prototype detector exhibited a spatial resolution of 2.5 mm as expected in the detector design. The detector performances including -ray sensitivity wil be presented.
