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Nakamura, Tatsuya; To, Kentaro; Koizumi, Tomokatsu; Kiyanagi, Ryoji; Ohara, Takashi; Ebine, Masumi; Sakasai, Kaoru
Proceedings of 2022 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room Temperature Semiconductor Detector Conference (2022 IEEE NSS MIC RTSD) (Internet), 2 Pages, 2022/11
A new thin position-sensitive scintillation neutron detectors have been developed to replace present scintillation detectors in SENJU diffractometer at J-PARC MLF. The SENJU diffractometer originally composed of 37 position-sensitive detectors, where each detector has neutron sensitive area of 256 
256 mm with a pixel size of 4 4 mm. To renew some original detectors the new detectors have been developed based on ZnS scintillator and wavelength-shifting fibers technology. The developed replacement detectors were designed with a thin thickness of 12 cm, which is 40% of the original detector. The new detectors have also improved detector performances to the original ones in terms of detection efficiency (
60% for 2-A neutrons) and count uniformity (5-8%). The produced six detector modules have been implemented to the beamline after checking their detector performances in the lab.
Nakamura, Tatsuya; To, Kentaro; Koizumi, Tomokatsu; Kiyanagi, Ryoji; Ohara, Takashi; Ebine, Masumi; Sakasai, Kaoru
Proceedings of 2020 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC 2020), Vol.1, p.483 - 484, 2021/09
Two-dimensional neutron detectors were developed for the extension of SENJU time-of-flight Laue single crystal neutron diffractometer in J-PARC MLF. The detectors are to be installed at the additional detector bank for the SENJU instrument. The detector module is made based on ZnS scintillator and wavelength-shifting fiber technology, where each detector module maintains a neutron-sensitive area of 256256 mm with a pixel size of 44 mm. To meet the tight space limitation in the instrument, the detector was designed as compact as possible. The detector has a depth of 170 mm, which is about 40% smaller than that of the original SENJU detector. All four produced detectors exhibited similar detector performances: detection efficiency 50-60% for 2-
neutron, 
Co gamma-ray sensitivity 110
, count uniformity 3-6%.
SGo, Shintaro*; Ideguchi, Eiji*; Yokoyama, Rin*; Aoi, Nori*; Azaiez, F.*; Furutaka, Kazuyoshi; Hatsukawa, Yuichi; Kimura, Atsushi; Kisamori, Keiichi*; Kobayashi, Motoki*; et al.
Physical Review C, 103(3), p.034327_1 - 034327_8, 2021/03
Times Cited Count：4 Percentile：54.4(Physics, Nuclear)Machida, Hideo*; Koizumi, Yu*; Wakai, Takashi; Takahashi, Koji*
Nihon Kikai Gakkai M&M 2019 Zairyo Rikigaku Kanfuarensu Koen Rombunshu (Internet), p.OS1307_1 - OS1307_5, 2019/11
This paper describes the fracture test and fracture analysis of a pipe under displacement control load. In order to grasp the fracture behavior of the circumferential through-wall cracked pipe, which is important in evaluating the feasibility of leak before break (LBB) in sodium cooled reactor piping, a fracture test in case of a circumferential throughwall crack in the weld line between an elbow and a straight pipe was carried out. From this test, it was found that no pipe fracture occurs in the displacement control loading condition even if a large circumferential through-wall crack (180
) was assumed. The fracture analysis of the pipe was carried out using Gurson's parameters set based on the tensile test results of the tested pipe material. The analytic results agree well with the test results, and it was found that it will be possible to predict the fracture behavior of sodium cooled reactor piping.
Kinsho, Michikazu; Kamiya, Junichiro; Koizumi, Oji*; Nasu, Shogo*
Proceedings of 15th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.668 - 670, 2018/08
Crystallinity, crystalline structure and internal force of thin films were measured by Laser Raman spectroscopy for the purpose of analyzing the fracture mechanism of the charge exchange foil due to beam hitting in this study. Thin films were used four types of HBC foil, pure carbon film (C foil) formed by arc discharge method, graphene, and carbon nanotube (CNT foil). As a result of changing the laser output and measuring the Raman peak shift of each foil, the HBC foil and the C foil had large Raman peak shift change, the D-band was negative and the G-band was opposite sign with positive. On the other hand, the graphene and the CNT foil showed small change in Raman peak shift, and both D-band and G-band were negative. From these results, it was found that a large stress occurs in the HBC foil and the C foil due to the heat load by the laser which was used for Raman spectrum measurements.
Kamiya, Junichiro; Kinsho, Michikazu; Abe, Kazuhiko*; Higa, Kyusaku*; Koizumi, Oji*
Journal of Vacuum Science and Technology A, 36(3), p.03E106_1 - 03E106_10, 2018/05
Times Cited Count：0 Percentile：0.01(Materials Science, Coatings & Films)The 3 GeV Rapid Cycling Synchrotron (RCS) in J-PARC aims to generate one of the highest power protons in the world, whose design extraction beam power is 1 MW. Beam pipes of alumina ceramics are used to prevent the induced current, which is caused by the rapid change of the magnetic field. In the beam injection section, ceramics beam pipes for a quadrupole magnet and a horizontal shift bump magnet are connected without bellows due to the very limited space. To improve maintainability, the ceramics beam pipes for the quadrupole magnet were newly designed to insert the bellows. We will report the design concept of the new alumina ceramics beam pipes with low spring constant bellows and the several results of the verification tests.
Kamiya, Junichiro; Kinsho, Michikazu; Abe, Kazuhiko*; Higa, Kyusaku*; Koizumi, Oji*
Proceedings of 14th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1222 - 1225, 2017/12
The 3 GeV Rapid Cycling Synchrotron aims to generate one of the highest power protons in the world. Beam pipes of alumina ceramics are used to prevent the induced current, which is caused by the rapid change of the magnetic field. In the beam injection section, ceramics beam pipes for a quadrupole magnet and a horizontal shift bump magnet are connected without bellows due to the narrow space. To improve maintainability, the ceramics beam pipes for the quadrupole magnet were newly designed. The end shape of ceramics unit duct was revised and 30 mm length are ensured to insert the bellows. The titanium bellows with low spring constant was successfully developed. Verification test for brazing of newly designed unit ducts and titanium sleeve was performed in order to examine the effect of the unique cross-sectional shape, racket shape fitting into 500 mm due to accept the injection beam and circulating beam passing through the injection quadrupole magnet.
Kimura, Atsushi; Harada, Hideo; Nakamura, Shoji; Iwamoto, Osamu; Toh, Yosuke; Koizumi, Mitsuo; Kitatani, Fumito; Furutaka, Kazuyoshi; Igashira, Masayuki*; Katabuchi, Tatsuya*; et al.
European Physical Journal A, 51(12), p.180_1 - 180_8, 2015/12
Times Cited Count：3 Percentile：30.26(Physics, Nuclear)Yamaji, Tatsuya*; Koizumi, Yasuo; Yamazaki, Kohei*; Otake, Hiroyasu*; Hasegawa, Koji*; Onuki, Akira*; Kanamori, Daisuke*
Konsoryu Shimpojiumu 2015 Koen Rombunshu (USB Flash Drive), 2 Pages, 2015/08
Experiments of condensing counter-current two-phase flow in a vertical pipe were performed. This study was intended to examine water accumulation in the up-flow side of steam generator U-tubes of a PWR during the reflux cooling stage of a small break LOCA. It has been apprehended that the water accumulation may result in temporary core liquid level depression. The inner diameter and the length of a test flow channel used in the experiments were 18 mm and 4 m, respectively. The experiments were performed by using steam and water at 0.1 MPa. Two kinds of experiments were conducted; visualization experiments by using a transparent test section and quantitative water accumulation evaluation experiments by using a brass test section. Even if water on the inner surface of the test pipe could not flow downward at the lower portion of the test pipe, a part of water became to flow downward at the upper portion of the test pipe since steam velocity decreased because of condensation. Thus, two-phase mixture level was formed in the upper portion of the test pipe, which resulted in the water accumulation in the pipe. The model to predict the water accumulation was proposed. It predicted the water accumulation reasonably well.
Koizumi, Yasuo; Ohira, Koji*
Proceedings of 16th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-16) (USB Flash Drive), 14 Pages, 2015/08
In this study, to examine the channel narrowing effect on the two-phase flow boiling heat transfer, single-phase flow and flow boiling heat transfer experiments were performed for a thin rectangular channel of the width W = 3 mm and the height 
= 1.25 mm 0.163 mm. When the hydraulic diameter became smaller than 1.06 mm, for the single-phase flow conditions, the heat transfer coefficient became smaller than that for a conventional size channel. In the flow boiling, churn flow appeared even at a low heat flux and a flow pattern was mainly the churn flow or/and the annular flow. The critical heat flux was higher than the value of Kutateladze correlation for the pool boiling. However, when the flow channel height became extremely narrow, measured critical heat flux became lower than the Kutateladze value. based on these results, the modification method to incorporate the channel narrowing effect into the heat transfer coefficient correlation was proposed.
SGo, Shintaro*; Ideguchi, Eiji*; Yokoyama, Rin*; Kobayashi, Motoki*; Kisamori, Keiichi*; Takaki, Motonobu*; Miya, Hiroyuki*; Ota, Shinsuke*; Michimasa, Shinichiro*; Shimoura, Susumu*; et al.
JPS Conference Proceedings (Internet), 6, p.030005_1 - 030005_4, 2015/06
) reactions with the ANNRI-Cluster Ge detectors at J-PARCHara, Kaoru; Goko, Shinji*; Harada, Hideo; Hirose, Kentaro; Kimura, Atsushi; Kin, Tadahiro*; Kitatani, Fumito; Koizumi, Mitsuo; Nakamura, Shoji; Toh, Yosuke; et al.
JAEA-Conf 2014-002, p.88 - 92, 2015/02
Toh, Yosuke; Ebihara, Mitsuru*; Kimura, Atsushi; Nakamura, Shoji; Harada, Hideo; Hara, Kaoru*; Koizumi, Mitsuo; Kitatani, Fumito; Furutaka, Kazuyoshi
Analytical Chemistry, 86(24), p.12030 - 12036, 2014/12
Times Cited Count：19 Percentile：56.78(Chemistry, Analytical)Non-destructive elemental analyses have been an indispensable tool for many fields of scientific research. Prompt -ray analysis and time of flight elemental analysis uses the energy of the rays and the energy of neutron resonances, respectively. In both analyses, a sample is irradiated with neutrons and rays are detected. Thus, these methods are similar and could be replaced by a single measurement. However, these methods have never been applied simultaneously before. We have first developed a novel technique which combines these methods by using an intense pulsed neutron beam. It allows us to obtain the results from both methods at the same time. Moreover, significant synergy has been achieved. Specifically, it will be used to quantify elemental concentrations in the sample that neither of these methods can be applied. Here, we demonstrate how it can be used to extract reliable information from unresolved peaks in the spectra.
Ogiwara, Norio; Kamiya, Junichiro; Shobuda, Yoshihiro; Kinsho, Michikazu; Koizumi, Oji*
Proceedings of 4th International Particle Accelerator Conference (IPAC '13) (Internet), p.3321 - 3323, 2014/07
Sn and 
Sn with J-PARC/MLF/ANNRIKimura, Atsushi; Hirose, Kentaro; Nakamura, Shoji; Harada, Hideo; Hara, Kaoru; Hori, Junichi*; Igashira, Masayuki*; Kamiyama, Takashi*; Katabuchi, Tatsuya*; Kino, Koichi*; et al.
Nuclear Data Sheets, 119, p.150 - 153, 2014/05
Times Cited Count：5 Percentile：37.68(Physics, Nuclear)
Pd and stable 
Pd nuclei at J-PARC/MLF/ANNRINakamura, Shoji; Kimura, Atsushi; Kitatani, Fumito; Ota, Masayuki; Furutaka, Kazuyoshi; Goko, Shinji*; Hara, Kaoru; Harada, Hideo; Hirose, Kentaro; Kin, Tadahiro*; et al.
Nuclear Data Sheets, 119, p.143 - 146, 2014/05
Times Cited Count：10 Percentile：56.9(Physics, Nuclear)We have started the measurements of the neutron-capture cross sections for stable Pd nuclei as well as the radioactive Pd. The neutron-capture cross-section measurements by the time-of flight method were performed using an apparatus called "Accurate Neutron-Nucleus Reaction measurement Instrument (ANNRI)" installed at the neutron Beam Line No.4 of the Materials and Life science experimental Facility (MLF) in the J-PARC. The neutron-capture cross sections of Pd and Pd have been measured in the neutron energy range from thermal to 300 eV. Some new information was obtained for resonances of these Pd nuclei.
Am(n,) at J-PARC/MLF/ANNRIHarada, Hideo; Ota, Masayuki; Kimura, Atsushi; Furutaka, Kazuyoshi; Hirose, Kentaro; Hara, Kaoru; Kin, Tadahiro*; Kitatani, Fumito; Koizumi, Mitsuo; Nakamura, Shoji; et al.
Nuclear Data Sheets, 119, p.61 - 64, 2014/05
Times Cited Count：19 Percentile：75.79(Physics, Nuclear) rays from the neutron resonances of 
Se and 
Se at the J-PARC/MLF/ANNRIHori, Junichi*; Yashima, Hiroshi*; Nakamura, Shoji; Furutaka, Kazuyoshi; Hara, Kaoru; Harada, Hideo; Hirose, Kentaro; Kimura, Atsushi; Kitatani, Fumito; Koizumi, Mitsuo; et al.
Nuclear Data Sheets, 119, p.128 - 131, 2014/05
Times Cited Count：4 Percentile：32.67(Physics, Nuclear)In this work, we measured the capture rays from the neutron resonances of Se and Se. A neutron time-of-flight method was adopted for the measurements with a 4
Ge spectrometer installed at the Accurate Neutron-Nucleus Reaction measurement Instrument (ANNRI) in the J-PARC Material and Life science experimental Facility (MLF). The -ray pulse-height spectra corresponding to the 27-eV resonance of Se and the 113-, 212-, 291-, 342-, 690- and 864-eV resonances of Se were obtained by gating on the TOF regions, respectively. The relative intensities of those primary transitions were derived and compared with the previous experimental data. For the 27-eV resonance of Se, a strong primary transition to the 293-keV state was observed. As for Se, the quite differences of the decay pattern were found between the resonances.
Np
at J-PARC/MLF/ANNRIHirose, Kentaro; Furutaka, Kazuyoshi; Hara, Kaoru; Harada, Hideo; Hori, Junichi*; Igashira, Masayuki*; Kamiyama, Takashi*; Katabuchi, Tatsuya*; Kimura, Atsushi; Kin, Tadahiro*; et al.
Nuclear Data Sheets, 119, p.48 - 51, 2014/05
Times Cited Count：1 Percentile：10.14(Physics, Nuclear)Kino, Koichi*; Furusaka, Michihiro*; Hiraga, Fujio*; Kamiyama, Takashi*; Kiyanagi, Yoshiaki*; Furutaka, Kazuyoshi; Goko, Shinji*; Hara, Kaoru; Harada, Hideo; Harada, Masahide; et al.
Nuclear Instruments and Methods in Physics Research A, 736, p.66 - 74, 2014/02
Times Cited Count：31 Percentile：91.62(Instruments & Instrumentation)