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Nakamura, Tatsuya; Katagiri, Masaki*; Tsutsui, Noriaki*; To, Kentaro; Rhodes, N. J.*; Schooneveld, E. M.*; Oguri, Hirofumi*; Noguchi, Yasunobu*; Sakasai, Kaoru; Soyama, Kazuhiko
Journal of Physics; Conference Series, 528, p.012043_1 - 012043_8, 2014/07
Times Cited Count:3 Percentile:84.33We have developed a ZnS/BO scintillator that has a high light output with less afterglow for neutron scattering instruments in the J-PARC/MLF. A commercial ZnS/LiF scintillator has widely been used for thermal neutron detection and its superior light output with low sensitivity has been proven. However its large afterglow followed with a primary emission light gives a limit on a detector count rate. A detector in the J-PARC/MLF should have a capability to cope with higher count rate than ever since the source flux is increasing up to 1 MW (300 kW at present). To address such problem we have developed the ZnS phosphor that exhibited a low after glow. We have also made a neutron-sensitive scintillator in combination with a BO by sintering method in search of high detector efficiency. The scintillator properties and the detector performances will be shown in the presentation.
Sakasai, Kaoru; To, Kentaro; Nakamura, Tatsuya; Harjo, S.; Moriai, Atsushi; Ito, Takayoshi; Abe, Jun; Aizawa, Kazuya; Soyama, Kazuhiko; Katagiri, Masaki*; et al.
Proceedings of 19th Meeting of the International Collaboration on Advanced Neutron Sources (ICANS-19) (CD-ROM), 5 Pages, 2010/07
Neutron detectors for Engineering Materials Diffractometer, named TAKUMI, at J-PARC have been developed under international cooperation between Rutherford Appleton Laboratory (RAL) and Japan Atomic Energy Agency (JAEA), and installed successfully at the end of March 2009. The detector size was 8051370217 mm which was about 1.5 times larger than those installed in ENGIN-X, ISIS facility, RAL. Neutrons are detected based on a nuclear reaction of Li(n, )H using ZnS/LiF scintillator. The data acquisition electronics and decoding module were also manufactured. The overall performances of the detectors have been tested using various sources. The results showed that the detectors had good performances such as a position resolution of 3 mm, a neutron detection efficiency of more than 50% at 1 -neutrons, and a -ray sensitivity of less than 10 at 1.3 MeV--ray by Co source, which met the requirements of TAKUMI, and they will be presented at the meeting.
Nakamura, Tatsuya; Schooneveld, E. M.*; Rhodes, N. J.*; Katagiri, Masaki; To, Kentaro; Sakasai, Kaoru; Soyama, Kazuhiko
Nuclear Instruments and Methods in Physics Research A, 606(3), p.675 - 680, 2009/07
Times Cited Count:12 Percentile:67(Instruments & Instrumentation)Nakamura, Tatsuya; Katagiri, Masaki; Birumachi, Atsushi; Ebine, Masumi; Tsutsui, Noriaki*; Soyama, Kazuhiko; Schooneveld, E. M.*; Rhodes, N. J.*
JAEA-Research 2008-116, 26 Pages, 2009/03
New ZnS scintillator, light reflector and digital signal processing modules were developed to upgrade the Japanese ENGIN-X type linear scintillation neutron detector. The developed ZnS/BO scintillator improved detector efficiency by a factor 1.2 for neutrons with a wavelength of 1 whilst the detector maintained similar sensitivity and multi-count ratio compared to the present AST (4:1) scintillator. The paint coating less light reflector was developed with an aluminum reflector with etched surface. The detector implemented with this reflector exhibited similar detector performances with paint coating reflectors, confirming feasibility of the reflector with long-term stability. The digital signal-processing module incorporating photon-counting method was successfully developed. The fully digitalized photon counting system improved a temperature stability of neutron counts significantly comparing to the present analogue system.
Nakamura, Tatsuya; Katagiri, Masaki; Hosoya, Takaaki*; Birumachi, Atsushi; Ebine, Masumi; Soyama, Kazuhiko; Schooneveld, E.*; Rhodes, N.*
JAEA-Research 2008-115, 33 Pages, 2009/03
A compact two-dimensional neutron detector was developed for iBIX instrument in the J-PARC/MLF. The specifications required for the detector were a spatial resolution of less than 1 mm, a detector efficiency of more than 50% for thermal neutrons, a sensitivity of less than 10, detector coverage of around 1515 cm with least dead area, compactness, modularity, and a pulse pair resolution of less than 2 s. The detector components were studied in detail and optimized for the purpose. The compact prototype detector that has a neutron sensitive area of 13.313.3 cm was made and feasibility of the detector was demonstrated successfully in the experiments at the ISIS pulsed neutron source.
Nakamura, Tatsuya; Schooneveld, E. M.*; Rhodes, N. J.*; Katagiri, Masaki; Tsutsui, Noriaki*; To, Kentaro; Sakasai, Kaoru; Soyama, Kazuhiko
2008 IEEE Nuclear Science Symposium Conference Record (CD-ROM), p.1215 - 1219, 2009/02
High detector efficiency ZnS/LiF scintillator and ZnS/BO ceramic scintillator were developed for a fiber-coded linear neutron detector for thermal neutron detection. Detector performances of the detector equipped with such scintillator strips were evaluated in terms of neutron detector efficiency, sensitivity, and quiet counts rate. The detector equipped with the ZnS/LiF scintillator that contained twice amount of Li compared to the conventional scintillator (ZnS/LiF scintillator produced by AST Co Ltd) exhibited about 30% higher detector efficiency for 1- neutrons. The fiber-coded detector equipped with the ZnS/BO ceramic scintillator also exhibited about 30% larger neutron counts than the detector made with the conventional scintillator and exhibited 40% shorter decay time than the conventional scintillator, indicating a potential for higher count rate capability.
Ebine, Masumi; Katagiri, Masaki; Birumachi, Atsushi; Sakasai, Kaoru; Nakamura, Tatsuya; Soyama, Kazuhiko; Sato, Setsuo*; Schooneveld, E.*; Rohdes, N.*
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no abstracts in English
Sakasai, Kaoru; Katagiri, Masaki; Nakamura, Tatsuya; Soyama, Kazuhiko; Birumachi, Atsushi; Sato, Setsuo*; Rhodes, N.*; Schooneveld, E.*
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no abstracts in English
Sakasai, Kaoru; Katagiri, Masaki; Nakamura, Tatsuya; Soyama, Kazuhiko; Birumachi, Atsushi; Sato, Setsuo*; Rhodes, N.*; Schooneveld, E.*
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no abstracts in English
Sakasai, Kaoru; Katagiri, Masaki; Nakamura, Tatsuya; Soyama, Kazuhiko; Birumachi, Atsushi; Sato, Setsuo*; Rhodes, N.*; Schooneveld, E.*
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no abstracts in English
Nakamura, Tatsuya; Katagiri, Masaki; Ebine, Masumi; Hosoya, Takaaki*; Soyama, Kazuhiko; Schooneveld, E.*; Rhodes, N.*
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We have developed pulsed neutron beam monitors with neutron scintillators composed of ZnS phosphors and neutron converters with very low neutron capture cross section. In order to develop neutron beam monitors with high S/N ratio and high counting rate characteristics, signal processing circuits with ISIS-type signal processing algorism were developed because ZnS phosphor has afterglow fluorescence and photomultipliers used for detection of fluorescence has many pulsed electric noises. Detection and signal processing characteristics as neutron beam monitors are reported.
Sakasai, Kaoru; Harjo, S.; Nakamura, Tatsuya; Moriai, Atsushi; Katagiri, Masaki; Soyama, Kazuhiko; Rhodes, N.*; Schooneveld, E.*
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no abstracts in English
Katagiri, Masaki; Tsutsui, Noriaki*; Kojima, Takahiro*; Schooneveld, E.*; Rhodes, N.*; To, Kentaro; Sakasai, Kaoru; Soyama, Kazuhiko; Nakamura, Tatsuya
no journal, ,
ZnS/BO ceramic scintillator was developed to improve a detector efficiency of the fibre-coded position sensitive neutron detector. The developed scintillator improved the detector efficiency by a factor 1.2 for neutrons with a wavelength of 1 .
Nakamura, Tatsuya; Sakasai, Kaoru; To, Kentaro; Katagiri, Masaki; Soyama, Kazuhiko; Rhodes, N.*; Schooneveld, E. M.*; Tsutsui, Noriaki*
no journal, ,
no abstracts in English
Sakasai, Kaoru; Nakamura, Tatsuya; Moriai, Atsushi; Harjo, S.; Ito, Takayoshi; Abe, Jun; Aizawa, Kazuya; Soyama, Kazuhiko; Rhodes, N. J.*; Schooneveld, E. M.*
no journal, ,
no abstracts in English
Sakasai, Kaoru; Nakamura, Tatsuya; Moriai, Atsushi; Harjo, S.; Ito, Takayoshi; Abe, Jun; Aizawa, Kazuya; Katagiri, Masaki; Soyama, Kazuhiko; Rhodes, N.*; et al.
no journal, ,
no abstracts in English
Sakasai, Kaoru; Nakamura, Tatsuya; Harjo, S.; Ito, Takayoshi; Abe, Jun; Aizawa, Kazuya; Katagiri, Masaki*; Soyama, Kazuhiko; Rhodes, N.*; Schooneveld, E.*
no journal, ,
no abstracts in English
Sakasai, Kaoru; Nakamura, Tatsuya; To, Kentaro; Soyama, Kazuhiko; Rhodes, N.*; Schooneveld, E.*
no journal, ,
no abstracts in English
Sakasai, Kaoru; Nakamura, Tatsuya; To, Kentaro; Moriai, Atsushi; Soyama, Kazuhiko; Rhodes, N. J.*; Schooneveld, E. M.*
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no abstracts in English
Sakasai, Kaoru; Nakamura, Tatsuya; To, Kentaro; Soyama, Kazuhiko; Rhodes, N.*; Schooneveld, E.*
no journal, ,
A prototype 1D-scintillaton detector has been developed. The detector has a small sensitive area of 42 mm 196 mm and a position resolution of 1.5 mm that is higher than that of TAKUMI detectors at MLF/J-PARC. The incident neutrons are detected based on ZnS/LiF scintillation techniques. The scintillation light produced in ZnS/LiF as a result of nuclear reaction of neutrons with 6Li nuclei is detected by photomultiplier tubes (PMTs) via optical fibers set in the back of the scintillator. To determine the incident neutron position and to reduce the number of PMTs, the 2Cn coding was adopted in the fiber arrangement. The electric signals from the PMTs are sent to the data acquisition electronics and the decoder. The fabricated detector showed excellent performances such as a neutron detection efficiency of 67 at a neutron wavelength of 1.8 and a sensitivity of less than 10 at a energy of 1.3 MeV.