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Li-glass detector to gamma rays by a coincidence methodIto, Fumiaki*; Lee, J.; Hironaka, Kota; Takahashi, Tone; Suzuki, Satoshi*; Mochimaru, Takanori*; Hori, Junichi*; Terada, Kazushi*; Koizumi, Mitsuo
Nuclear Instruments and Methods in Physics Research A, 1064, p.169465_1 - 169465_9, 2024/07
Koizumi, Mitsuo; Mochimaru, Takanori*; Hironaka, Kota; Takahashi, Tone; Yamanishi, Hirokuni*; Wakabayashi, Genichiro*
Nuclear Instruments and Methods in Physics Research A, 1042, p.167424_1 - 167424_6, 2022/11
Times Cited Count：2 Percentile：48.47(Instruments & Instrumentation)no abstracts in English
Koizumi, Mitsuo; Takahashi, Tone; Hironaka, Kota; Mochimaru, Takanori*; Yamanishi, Hirokuni*; Wakabayashi, Genichiro*
Annual Report of Cooperative Researches at Kindai University Reactor, 2020, p.76 - 80, 2021/12
no abstracts in English
Mochimaru, Takanori*; Koizumi, Mitsuo; Takahashi, Tone; Hironaka, Kota; Kimura, Yoshiki; Sato, Yuki; Terasaka, Yuta; Yamanishi, Hirokuni*; Wakabayashi, Genichiro*
Dai-42-Kai Nihon Kaku Busshitsu Kanri Gakkai Nenji Taikai Kaigi Rombunshu (Internet), 4 Pages, 2021/11
no abstracts in English
Sakakibara, Takanori*; Takahashi, Satoru*; Kawabata, Kuniaki; Oda, Shoji*
2021 IEEE/SICE International Symposium on System Integration (SII 2021), Vol.2, p.517 - 523, 2021/07
Times Cited Count：0 Percentile：0.00(Computer Science, Interdisciplinary Applications)In biology, it is expected to understand the mechanism of herd development by analyzing crowd behavior. Currently, medaka (Oryzias latipes) is often used when conducting such research because of its ease of breeding and experimentation. However, when conducting such studies, it is very difficult to manually obtain herd data. In this article, in order to analyze the behavior of medaka, we will introduce a method to automatically extract the swimming trajectory of medaka from time-series images and acquire the data necessary for behavior analysis. In particular, the improvement of extraction accuracy is achieved by processing the overlap state and adjoin state of medaka in the image.
Miao, P.*; Tan, Z.*; Lee, S. H.*; Ishikawa, Yoshihisa*; Torii, Shuki*; Yonemura, Masao*; Koda, Akihiro*; Komatsu, Kazuki*; Machida, Shinichi*; Sano, Asami; et al.
Physical Review B, 103(9), p.094302_1 - 094302_18, 2021/03
Times Cited Count：2 Percentile：16.40(Materials Science, Multidisciplinary)The layered perovskite PrBaCo
O
demonstrates a strong negative thermal expansion (NTE) which holds potential for being fabricated into composites with zero thermal expansion. The NTE was found to be intimately associated with the spontaneous magnetic ordering, known as magneto-volume effect (MVE). Here we report with compelling evidences that the continuous-like MVE in PrBaCoO is intrinsically of discontinuous character, originating from an magnetoelectric transition from an antiferromagnetic insulating large-volume (AFILV) phase to a ferromagnetic less-insulating small-volume (FLISV) phase. Furthermore, the magnetoelectric effect (ME) shows high sensitivity to multiple external stimuli such as temperature, carrier doping, hydrostatic pressure, magnetic field etc. In contrast to the well-known ME such as colossal magnetoresistance and multi-ferroic effect which involve symmetry breaking of crystal structure, the ME in the cobaltite is purely isostructural. Our discovery provides a new path way to realizing the ME as well as the NTE, which may find applications in new techniques.
Kondo, Yasuhiro; Hirano, Koichiro; Ito, Takashi; Kikuzawa, Nobuhiro; Kitamura, Ryo; Morishita, Takatoshi; Oguri, Hidetomo; Okoshi, Kiyonori; Shinozaki, Shinichi; Shinto, Katsuhiro; et al.
Journal of Physics; Conference Series, 1350, p.012077_1 - 012077_7, 2019/12
Times Cited Count：1 Percentile：51.67(Physics, Particles & Fields)We have upgraded a 3-MeV linac at J-PARC. The ion source is same as the J-PARC linac's, and the old 30-mA RFQ is replaced by a spare 50-mA RFQ, therefore, the beam energy is 3 MeV and the nominal beam current is 50 mA. The main purpose of this system is to test the spare RFQ, but also used for testing of various components required in order to keep the stable operation of the J-PARC accelerator. The accelerator has been already commissioned, and measurement programs have been started. In this paper, present status of this 3-MeV linac is presented.
Pyeon, C. H.*; Vu, T. M.*; Yamanaka, Masao*; Sugawara, Takanori; Iwamoto, Hiroki; Nishihara, Kenji; Kim, S. H.*; Takahashi, Yoshiyuki*; Nakajima, Ken*; Tsujimoto, Kazufumi
Journal of Nuclear Science and Technology, 55(2), p.190 - 198, 2018/02
Times Cited Count：16 Percentile：84.46(Nuclear Science & Technology)At the Kyoto University Critical Assembly, a series of reaction rate experiments is conducted on the accelerator-driven system (ADS) with spallation neutrons generated by the combined use of 100 MeV protons and a lead and bismuth target in the subcritical state. The reaction rates are measured by the foil activation method to obtain neutron spectrum information on ADS. Numerical calculations are performed with MCNP6.1 and JENDL/HE-2007 for high-energy protons and spallation process, JENDL-4.0 for transport and JENDL/D-99 for reaction rates. The reaction rates depend on subcriticality is revealed by the accuracy of the C/E (calculation/experiment) values. Nonetheless, the accuracy of the reaction rates at high-energy thresholds remains an important issue in the fixed-source calculations.
Kawamura, Seiko; Oku, Takayuki; Watanabe, Masao; Takahashi, Ryuta; Munakata, Koji*; Takata, Shinichi; Sakaguchi, Yoshifumi*; Ishikado, Motoyuki*; Ouchi, Keiichi*; Hattori, Takanori; et al.
Journal of Neutron Research, 19(1-2), p.15 - 22, 2017/11
Sample environment (SE) team at the Materials and Life Science Experimental Facility (MLF) in J-PARC has worked on development and operation of SE equipment and devices. All the members belong to one sub-team at least, such as Cryogenic and magnet, High temperature, High pressure, Soft matter and special environment including Pulse magnet, Hydrogen environment, Light irradiation and 
He spin filter. Cryostats, a magnet, furnaces, a VX-6-type Paris-Edinburgh press and a prototype of a Spin-Exchange Optical Pumping (SEOP) based He spin filter for polarized neutron beam experiments are in operation. Furthermore, a prototype of compact power supply for a pulsed magnet system is currently developed. In the J-PARC Research Building, several pieces of equipment for softmatter research such as a rheometer and a gas and vapor adsorption measurement instrument have been prepared.
Pyeon, C. H.*; Fujimoto, Atsushi*; Sugawara, Takanori; Iwamoto, Hiroki; Nishihara, Kenji; Takahashi, Yoshiyuki*; Nakajima, Ken*; Tsujimoto, Kazufumi
Nuclear Science and Engineering, 185(3), p.460 - 472, 2017/03
Times Cited Count：11 Percentile：71.88(Nuclear Science & Technology)Sensitivity and uncertainty analyses of lead (Pb) isotope cross sections are conducted with the use of sample reactivity experiments at the Kyoto University Critical Assembly (KUCA). With the combined use of the SRAC2006 and MARBLE code systems, attempts are made to precisely examine the contributions of the reactions and energy regions of Pb isotope cross sections to reactivity based on the covariance data of JENDL-4.0. Moreover, the effect of decreasing uncertainty is discussed in terms of the accuracy of sample reactivity by applying the cross section adjustment method to the uncertainty analyses. From the results of the sensitivity and uncertainty analyses, the reliability of Pb isotope cross sections, such as the Pb isotope covariance data of JENDL-4.0, is compared with the JENDL-3.3, ENDF/B-VII.0, and JEFF-3.1 libraries.
(Al,Ga)
O
scintillator Compton camera mounted on an unmanned helicopterShikaze, Yoshiaki; Nishizawa, Yukiyasu; Sanada, Yukihisa; Torii, Tatsuo; Jiang, J.*; Shimazoe, Kenji*; Takahashi, Hiroyuki*; Yoshino, Masao*; Ito, Shigeki*; Endo, Takanori*; et al.
Journal of Nuclear Science and Technology, 53(12), p.1907 - 1918, 2016/12
Times Cited Count：37 Percentile：96.33(Nuclear Science & Technology)The Compton camera was improved for use with the unmanned helicopter. Increase of the scintillator array from 4
4 to 88 and expanse of the distance between the two layers contributed to the improvements of detection efficiency and angular resolution, respectively. Measurements were performed over the riverbed of the Ukedo river of Namie town in Fukushima Prefecture. By programming of flight path and speed, the areas of 65 m 60 m and 65 m 180 m were measured during about 20 and 30 minutes, respectively. By the analysis the air dose rate maps at 1 m height were obtained precisely with the angular resolution corresponding to the position resolution of about 10 m from 10 m height. Hovering flights were executed over the hot spot areas for 10-20 minutes at 5-20 m height. By using the reconstruction software the 
-ray images including the hot spots were obtained with the angular resolution same as that evaluated in the laboratory (about 10
).
Pyeon, C. H.*; Fujimoto, Atsushi*; Sugawara, Takanori; Yagi, Takahiro*; Iwamoto, Hiroki; Nishihara, Kenji; Takahashi, Yoshiyuki*; Nakajima, Ken*; Tsujimoto, Kazufumi
Journal of Nuclear Science and Technology, 53(4), p.602 - 612, 2016/04
Times Cited Count：21 Percentile：88.40(Nuclear Science & Technology)Sample reactivity experiments on the uncertainty analyses of Pb nuclear data are carried out by substituting Al plates for Pb ones at the Kyoto University Critical Assembly, as part of basic research on Pb-Bi for the coolant. Numerical simulations of sample reactivity experiments are performed with the Monte Carlo calculation code MCNP6.1 together with four nuclear data libraries JENDL-3.3, JENDL-4.0, ENDF/B-VII.0 and JEFF-3.1, to examine the accuracy of cross-section uncertainties of Pb isotopes by comparing measured and calculated sample reactivities. A library update from JENDL-3.3 to JENDL-4.0 is demonstrated by the fact that the difference between Pb isotopes of the two JENDL libraries is dominant in the comparative study, through the experimental analyses of sample reactivity by the MCNP approach. In addition, JENDL-4.0 reveals a slight difference from ENDF/B-VII.0 in all Pb isotopes and 
Al, and from JEFF-3.1 in 
U and Al.
, Na, I
and HTO in granodiorite; Laboratory-scale results and their extrapolation to the in situ conditionTachi, Yukio; Ebina, Takanori*; Takeda, Chizuko*; Saito, Toshihiko*; Takahashi, Hiroaki*; Ouchi, Yuji*; Martin, A. J.*
Journal of Contaminant Hydrology, 179, p.10 - 24, 2015/08
Times Cited Count：29 Percentile：74.00(Environmental Sciences)Matrix diffusion and sorption are important processes in the assessment of radionuclide transport in crystalline rocks. Diffusion and sorption parameters for Cs, Na, I and HTO were determined by through-diffusion and batch sorption experiments using granodiorite samples from the Grimsel Test Site, Switzerland. The De values were in the order Cs, Na, HTO, I. The capacity factor and Kd values show the same trends. The dual depth profiles for Cs and Na can be interpreted by a near-surface Kd increment. The microscopic analysis indicated that this is caused by high porosity and sorption capacities in disturbed biotite minerals on the sample surface. The Kd values derived from the dual profiles are likely to correspond to Kd dependence on the grain sizes of crushed samples in the batch experiments. The results of the in situ LTD experiments were interpreted reasonably well by using transport parameters derived from laboratory data and extrapolating them to in situ conditions.
Terauchi, Masami*; Takahashi, Hideyuki*; Handa, Nobuo*; Murano, Takanori*; Koike, Masato; Imazono, Takashi; Koeda, Masaru*; Nagano, Tetsuya*; Sasai, Hiroyuki*; Oue, Yuki*; et al.
Microscopy and Microanalysis, 20(Suppl.3), p.682 - 683, 2014/08
X-rays originate form electronic transitions from valence bands (VB, bonding electron states) to inner-shell electron levels inform us energy states of bonding electrons. We have developed the SXES spectrometers attaching to TEM, EPMA, and SEM. A spectrometer has an energy range of 50-4000 eV by using four varied-line-spacing gratings. Applications of TEM-SXES instrument to C
have revealed characteristic energy distribution of bonding electrons. Carbon K-emission spectra of C crystals showed that both the peak structures in 
- and 
-bands and the characteristic dip structure between the - and -bonding states in monomer-C disappear in the most polymerized-C crystals. Bulk specimens were examined by applying SXES to a SEM. Al L-emission spectra of intermetallic compounds of AlAu, AlCo, and aluminum showed different intensity distributions due to different band structures originating from different crystal structures.
Takahashi, Hideyuki*; Handa, Nobuo*; Murano, Takanori*; Terauchi, Masami*; Koike, Masato; Kawachi, Tetsuya; Imazono, Takashi; Hasegawa, Noboru; Koeda, Masaru*; Nagano, Tetsuya*; et al.
Microscopy and Microanalysis, 20(Suppl.3), p.684 - 685, 2014/08
A novel wavelength dispersive soft X-ray emission spectrometer (SXES) having a X-ray energy range of 50-210 eV has been developed. One feature is that the SXES is parallel detection of the signals so that it can be used like a conventional energy dispersive spectrometer. The other is a high energy resolution, which is about 0.2 eV at Al-L comparable to those revealed by XPS and EELS. These features enable us to obtain meaningful information about chemical bonding in various bulk samples. The SXES can detect Li-K emission spectrum. In the case of an anode electrode of a lithium ion battery (LIB), two types of lithium peaks are observed: one lower energy peak at 50 eV and the other higher energy peak at 54 eV. It was found that the former peak corresponds to the amount of charging, whereas the latter corresponds to the metallic state of lithium.
Terauchi, Masami*; Koshiya, Shogo*; Sato, Futami*; Takahashi, Hideyuki*; Handa, Nobuo*; Murano, Takanori*; Koike, Masato; Imazono, Takashi; Koeda, Masaru*; Nagano, Tetsuya*; et al.
Microscopy and Microanalysis, 20(3), p.692 - 697, 2014/06
Times Cited Count：34 Percentile：90.80(Materials Science, Multidisciplinary)Electron beam induced soft-X-ray emission spectroscopy (SXES) by using a grating spectrometer has been introduced to a conventional scanning electron microscope (SEM) for characterizing desired specimen areas of bulk materials. The spectrometer was designed as a grazing-incidence flat-field optics by using aberration corrected (varied-line-spacing) gratings and a multi-channel-plate detector combined with a charge-coupled-device camera, which has already applied for a transmission electron microscope. The best resolution was confirmed as 0.13 eV at Mg L-emission (50 eV), which value is comparable to that of recent dedicated electron energy-loss spectroscopy instruments. This SXES-SEM instrument presents density of states of simple metals of bulk Mg and Li. Apparent band structure effects have been observed in Si L-emission of Si-wafer, P L-emission of GaP-wafer, and Al L-emissions of intermetallic compounds of AlCo, AlPd, AlPt, and AlAu.
Takahashi, Nobuaki*; Murata, Hirohiko*; Mitsubori, Hitoshi*; Sakuraba, Junji*; Soga, Tomohiro*; Aoki, Yasushi*; Kato, Takanori*; Saito, Yuichi; Yamada, Keisuke; Ikenaga, Noriaki*; et al.
Review of Scientific Instruments, 85(2), p.02C306_1 - 02C306_3, 2014/02
Times Cited Count：2 Percentile：11.13(Instruments & Instrumentation)Terauchi, Masami*; Takahashi, Hideyuki*; Handa, Nobuo*; Murano, Takanori*; Koike, Masato; Kawachi, Tetsuya; Imazono, Takashi; Hasegawa, Noboru; Koeda, Masaru*; Nagano, Tetsuya*; et al.
JAEA-Conf 2013-001, p.77 - 80, 2013/09
We have been developing a soft X-ray emission spectroscopy (SXES) instrument for electron microscopes (TEM, EPMA/SEM) with an extension of detectable energy range to 50-4000 eV. An introduction of valence electron spectroscopy with microscopy will supply fruitful information on bonding electrons, which cannot be obtained by EELS and EDS. For extend the lowest (or highest) detection energy upto 50 eV (or 4000 eV), a new laminar-type varied-line-spacing (VLS) grating, JS50XL, (or JS4000) has designed and manufactured. JS50XL and JS4000 having 1200 and 2400 lines/mm as well as coated by Au and a new multilayer-structure of W/B
C for a wide-band energy region of 2000-3800 eV, respectively. Those gratings were installed and tested in a SXES spectrometer attached to a TEM. The extension in lowest detection energy was confirmed by Mg-L emission (JS50XL). The energy resolution was 0.2 eV at Fermi edge of 49.5 eV. It can be also seen a sharp Fermi edge for Li-K emission spectrum of metal-Li. The high energy resolution was confirmed by Te-La emission at 3.8 keV (JS4000). The full width at half maximum of the peak was 27 eV. The detection energy range was successfully extended by using the two new VLS-gratings.
Takahashi, Hideyuki*; Handa, Nobuo*; Murano, Takanori*; Koike, Masato; Kawachi, Tetsuya; Imazono, Takashi; Hasegawa, Noboru; Terauchi, Masami*; Koeda, Masaru*; Nagano, Tetsuya*; et al.
JAEA-Conf 2013-001, p.13 - 15, 2013/09
A very unique high performance soft X-ray emission spectrometer (SXES) has successfully been developed which can be attached not only to transmission electron microscopes (TEMs), but also to scanning electron microscopes (SEMs) as well as electron probe microanalyzers (EPMAs). To extend the analyzed energy ranges, a newly designed laminar-type varied-line-spacing (VLS) grating JS50XL, for a lower energy range, 50-170 eV, and a multilayered VLS grating JS4000, for a higher energy range, 2000-4000 eV, have been developed and installed to this spectrometer. Application software has also been developed for a commercial use of SXES in several fields such as battery materials, steel and alloys, and electron devices. The appearance of this spectrometer attached to EPMA and a few results acquired are shown in the following figures. This development has been conducted as one of the projects of Collaborative Development of Innovative Seeds (Practicability verification stage) by Japan Science and Technology Agency.
Imazono, Takashi; Koike, Masato; Kawachi, Tetsuya; Hasegawa, Noboru; Koeda, Masaru*; Nagano, Tetsuya*; Sasai, Hiroyuki*; Oue, Yuki*; Yonezawa, Zeno*; Kuramoto, Satoshi*; et al.
Proceedings of SPIE, Vol.8848, p.884812_1 - 884812_14, 2013/09
Times Cited Count：7 Percentile：93.95(Optics)We have developed an objective soft X-ray flat-field spectrograph to be able to attach to electron microscopes. This spectrograph has two attractive features. One is that it is designed to cover a wide energy range of 50-4000 eV by using four varied-line-spacing holographic gratings optimized for 50-200 eV, 155-350 eV, 300-2200 eV, and 2000-4000 eV. They can be accommodated in the single spectrograph. The other is a newly invented W/B
C multilayer coating covering the 2000-4000 eV range. It can enhance the diffraction efficiency above a practical level of 
% at a constant incidence angle in the whole energy range.
