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O-BO
-SiO glass plate with bearing NiO for heat center and structural probeTomita, Kana*; Kishi, Tetsuo*; Matsumura, Daiju; Yano, Tetsuji*
Journal of Non-Crystalline Solids, 597, p.121891_1 - 121891_10, 2022/12
Times Cited Count：1 Percentile：14.66(Materials Science, Ceramics)Miyabe, Masabumi; Satou, Yukihiko; Wakaida, Ikuo; Terabayashi, Ryohei*; Sonnenschein, V.*; Tomita, Hideki*; Zhao, Y.*; Sakamoto, Tetsuo*
Journal of Physics B; Atomic, Molecular and Optical Physics, 54(14), p.145003_1 - 145003_8, 2021/07
Times Cited Count：0 Percentile：0.01(Optics)Two-color two-step photoionization optogalvanic spectroscopy was performed using high-repetition-rate titanium sapphire lasers and a uranium hollow cathode lamp to find the two-step resonance ionization schemes of uranium. Many ionization transitions were observed by exciting uranium atoms in a ground state into five, even parity, excited levels with the first-step laser and by scanning the second-step laser wavelengths. By blocking the first-step laser, single-color, two-photon ionization transitions were also identified. From these results, we have found more than 50 odd-parity autoionizing levels of uranium in the energy, ranging from the ionization potential (49958.4 cm
) to 51150 cm. The determined energy levels are within 1 cm of previously reported values.
Ito, Chikara; Maeda, Shigetaka; Inoue, Toshihiko; Tomita, Hideki*; Iguchi, Tetsuo*
Radiation Protection, 40(6), p.491 - 495, 2020/11
A highly accurate and precise technique for measurement of the 
Nb(n,n')
Nb reaction rate was established for the material surveillance tests, etc. in fast reactors. The self-absorption effect on the measurement of the characteristic X-rays emitted by Nb was decreased by the solution and evaporation to dryness of niobium dosimeter. A highly precise count of the number of Nb atoms was obtained by measuring the niobium solution concentration using inductively coupled plasma mass spectrometry. X-rays of Nb were measured accurately by means of comparing the X-ray intensity of irradiated niobium solution with that of the solution in which stable Nb was added. The difference between both intensities indicates the effect of 
Ta, which is generated from an impurity tantalum, and the intensity of X-rays from Nb was evaluated. Measurement error of the Nb(n,n')Nb reaction rate was reduced to be less than 4%, which was equivalent to the other reaction rate errors of dosimeters used for Joyo dosimetry. In addition, an advanced technique using Resonance Ionization Mass Spectrometry was proposed for the precise measurement of Nb yield, and Nb will be resonance-ionized selectively by discriminating the hyperfine splitting of the atomic energy levels between Nb and Nb at high resolution.
He
excimer cluster tracers in superfluid helium-4 via neutron-
He absorption reactionSonnenschein, V.*; Tsuji, Yoshiyuki*; Kokuryu, Shoma*; Kubo, Wataru*; Suzuki, So*; Tomita, Hideki*; Kiyanagi, Yoshiaki*; Iguchi, Tetsuo*; Matsushita, Taku*; Wada, Nobuo*; et al.
Review of Scientific Instruments, 91(3), p.033318_1 - 033318_12, 2020/03
Times Cited Count：0 Percentile：0(Instruments & Instrumentation)Kurihara, Momo*; Yasutaka, Tetsuo*; Aono, Tatsuo*; Ashikawa, Nobuo*; Ebina, Hiroyuki*; Iijima, Takeshi*; Ishimaru, Kei*; Kanai, Ramon*; Karube, Jinichi*; Konnai, Yae*; et al.
Journal of Radioanalytical and Nuclear Chemistry, 322(2), p.477 - 485, 2019/11
Times Cited Count：2 Percentile：21.58(Chemistry, Analytical)We assessed the repeatability and reproducibility of methods for determining low dissolved radiocesium concentrations in freshwater in Fukushima. Twenty-one laboratories pre-concentrated three of 10 L samples by five different pre-concentration methods (prussian-blue-impregnated filter cartridges, coprecipitation with ammonium phosphomolybdate, evaporation, solid-phase extraction disks, and ion-exchange resin columns), and activity of radiocesium was measured. The z-scores for all of the 
Cs results were within 
2, indicating that the methods were accurate. The relative standard deviations (RSDs) indicating the variability in the results from different laboratories were larger than the RSDs indicating the variability in the results from each separate laboratory.
He
clusters via neutron-He absorption reaction toward visualization of full velocity field in quantum turbulenceMatsushita, Taku*; Sonnenschein, V.*; Guo, W.*; Hayashida, Hirotoshi*; Hiroi, Kosuke; Hirota, Katsuya*; Iguchi, Tetsuo*; Ito, Daisuke*; Kitaguchi, Masaaki*; Kiyanagi, Yoshiaki*; et al.
Journal of Low Temperature Physics, 196(1-2), p.275 - 282, 2019/07
Times Cited Count：1 Percentile：4.76(Physics, Applied)Sakamoto, Tetsuo*; Morita, Masato*; Kanenari, Keita*; Tomita, Hideki*; Sonnenschein, V.*; Saito, Kosuke*; Ohashi, Masaya*; Kato, Kotaro*; Iguchi, Tetsuo*; Kawai, Toshihide*; et al.
Analytical Sciences, 34(11), p.1265 - 1270, 2018/11
Times Cited Count：8 Percentile：31.98(Chemistry, Analytical)
-ray for improvement neutron emission profile measurementUchida, Yuki*; Takada, Eiji*; Fujisaki, Akihiro*; Isobe, Mitsutaka*; Ogawa, Kunihiro*; Shinohara, Koji; Tomita, Hideki*; Kawarabayashi, Jun*; Iguchi, Tetsuo*
Review of Scientific Instruments, 85(11), p.11E118_1 - 11E118_4, 2014/11
Times Cited Count：9 Percentile：40.01(Instruments & Instrumentation)-ray fields with novel nuclear emulsion techniqueIshihara, Kohei*; Takagi, Keisuke*; Minato, Haruna*; Kawarabayashi, Jun*; Tomita, Hideki*; Maeda, Shigetaka; Naka, Tatsuhiro*; Morishima, Kunihiro*; Nakano, Toshiyuki*; Nakamura, Mitsuhiro*; et al.
Radiation Measurements, 55, p.79 - 82, 2013/08
Times Cited Count：1 Percentile：10.69(Nuclear Science & Technology)In order to measure the neutron under a condition of high intensity of -ray background, we made new nuclear emulsion based on non-sensitized OPERA emulsion which had small AgBr grain size (AgBr grain size of 60, 90 and 160 nm). The sensitivity of this new emulsion, which was a correlation between stopping power and grain density, was estimated experimentally by irradiating neutrons with several energies. We also simulated the response to -ray induced electrons and compared with some experimental results by using 
Co source. The results showed that there might be a threshold energy deposited in one AgBr grain under which it was impossible to develop. We estimated efficiency to the -ray and the neutron with this obtained response of the new emulsion.
Kawahara, Hirotaka; Yamamoto, Masaya; Tomita, Etsuo; Takamatsu, Misao
JAEA-Technology 2012-030, 50 Pages, 2012/09
JAEA-Technology-2012-030.pdf:6.16MB
JAEA-Technology-2012-030-appendix(CD-ROM).zip:21.06MB
In the experimental fast reactor Joyo, in-vessel observation results showed that 6 pins which were connected between the handling head and the wrapper tube joint of the instrumented test subassembly (MARICO-2) were disconnected. Therefore, in order to confirm whether the disconnected 6 pins will influence reactor's safety or not, loose parts behavior in the reactor vessel was evaluated.
Ueda, Yoshio*; Oya, Kaoru*; Ashikawa, Naoko*; Ito, Atsushi*; Ono, Tadayoshi*; Kato, Daiji*; Kawashima, Hisato; Kawamura, Gakushi*; Kenmotsu, Takahiro*; Saito, Seiki*; et al.
Purazuma, Kaku Yugo Gakkai-Shi, 88(9), p.484 - 502, 2012/09
no abstracts in English
field using new type of nuclear emulsionKawarabayashi, Jun*; Ishihara, Kohei*; Takagi, Keisuke*; Tomita, Hideki*; Iguchi, Tetsuo*; Naka, Tatsuhiro*; Morishima, Kunihiro*; Maeda, Shigetaka
Journal of ASTM International (Internet), 9(3), 5 Pages, 2012/03
In order to measure the neutron from a spent fuel assembly in fast breeder reactor precisely, we made new nuclear emulsion based on non-sensitized OPERA film with AgBr grain size of 60, 90 and 160 nm. The efficiency for 
Cf neutron of the new emulsion was calculated to be 0.7
10
which energy ranged from 0.3 to 2 MeV that agrees with preliminary estimated value from experimental results. The sensitivity of the new emulsion was also estimated experimentally by irradiating 565 KeV and 14 MeV neutrons and found that the emulsion with the AgBr grain size of 60 nm showed the lowest sensitivity among these three emulsions but still had enough sensitivity for proton. Also, there was a suggestion from the experimental data that there was a threshold LET of 15 KeV/
m for our new emulsion below which no silver cluster was developed. Further development of the response of nuclear emulsion with a few tens of nano-meter AgBr size is next step of this study.
Koizumi, Satoshi; Zhao, Y.; Tomita, Yoko*; Kondo, Tetsuo*; Iwase, Hiroki; Yamaguchi, Daisuke; Hashimoto, Takeji
European Physical Journal E, 26(1-2), p.137 - 142, 2008/05
Times Cited Count：55 Percentile：86.02(Chemistry, Physical)no abstracts in English
Koizumi, Satoshi; Kondo, Tetsuo*; Tomita, Yoko*; Iwase, Hiroki; Yamaguchi, Daisuke; Hashimoto, Takeji
no journal, ,
no abstracts in English
Yukawa, Kyohei*; Asai, Keisuke*; Tomita, Hideki*; Iguchi, Tetsuo*; Iwai, Haruki*; Kawarabayashi, Jun*; Konno, Chikara
no journal, ,
We are developing a new neutron spectrometer to apply to the measurement of the D/T burning ratio in the ITER high-power operation region. This system is based on the conventional double crystal TOF method and consists of a water cell and several pairs of scintillators. A water cell is inserted before the first scintillator of the TOF system and acts as a radiator or neutron scattering material. Because DD neutrons have a larger cross section of elastic scattering with hydrogen than DT neutrons, the elastic scattering in the radiator enhances the relative ratio of DD/DT intensity by approximately three times before entering the TOF system. The enhancement of the relative intensity of DD neutrons makes the detection of DD neutrons easier. The feasibility of this method as a neutron spectrometer has been verified through a preliminary experiment using a DT neutron beam (20 mm
) at the Fusion Neutronics Source, Japan Atomic Energy Agency, which includes a small amount of DD neutrons.
Zhao, Y.; Koizumi, Satoshi; Hashimoto, Takeji; Tomita, Yoko*; Kondo, Tetsuo*
no journal, ,
Koizumi, Satoshi; Tomita, Yoko*; Zhao, Y.; Iwase, Hiroki*; Yamaguchi, Daisuke; Kondo, Tetsuo*; Hashimoto, Takeji; Masui, Tomomi
no journal, ,
no abstracts in English
Kawahara, Hirotaka; Takamatsu, Misao; Yamamoto, Masaya; Tomita, Etsuo
no journal, ,
no abstracts in English
Zhao, Y.; Koizumi, Satoshi; Hashimoto, Takeji; Tomita, Yoko*; Kondo, Tetsuo*
no journal, ,
Tomita, Hideki*; Iwai, Haruki*; Iguchi, Tetsuo*; Kawarabayashi, Jun*; Isobe, Mitsutaka*; Konno, Chikara
no journal, ,
Neutron spectrometer based on coincident counting of associated particles has been developed for deuterium plasma diagnostics on Large Helical Device (LHD) at National Institute for Fusion Science. Efficient detection of 2.5 MeV neutron with high energy resolution would achievable by coincident detection of a scattered neutron and a recoiled proton associated to a elastic scattering of incident neutron in a plastic scintillator as a radiator. Calculated neutron spectra from deuterium plasma heated by neutral beam injection indicate that the energy resolution of less than 7% is required for the spectrometer to evaluate energetic deuterium confinement. By using a prototype of the proposed spectrometer, the energy resolution of 6.3% and the detection efficiency of 3.310
counts/neutron were experimentally demonstrated for 2.5 MeV mono-energetic neutron, respectively.
