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-ray elastic scatteringOmer, M.; Shizuma, Toshiyuki*; Koizumi, Mitsuo; Hajima, Ryoichi*; Hashimoto, Satoshi*; Miyamoto, Shuji*
LASTI Annual Report, 24, p.20 - 22, 2023/12
-state of a 
hypernucleus, 
Yoshimoto, Masahiro*; Fujita, Manami; Hashimoto, Tadashi; Hayakawa, Shuhei; Ichikawa, Yudai; Ichikawa, Masaya; Imai, Kenichi*; Nanamura, Takuya; Naruki, Megumi; Sako, Hiroyuki; et al.
Progress of Theoretical and Experimental Physics (Internet), 2021(7), p.073D02_1 - 073D02_19, 2021/07
Times Cited Count：13 Percentile：80.44(Physics, Multidisciplinary)
-
N systemHayakawa, Shuhei; Fujita, Manami; Hasegawa, Shoichi; Hashimoto, Tadashi; Hosomi, Kenji; Ichikawa, Yudai; Imai, Kenichi*; Nanamura, Takuya; Naruki, Megumi; Sako, Hiroyuki; et al.
Physical Review Letters, 126(6), p.062501_1 - 062501_6, 2021/02
Times Cited Count：34 Percentile：95.02(Physics, Multidisciplinary)Nakayama, Shinsuke; Iwamoto, Osamu; Iwamoto, Nobuyuki; Hashimoto, Shintaro
Kaku Deta Nyusu (Internet), (123), p.53 - 59, 2019/06
The 2019 International Conference on Nuclear Data for Science and Technology (ND2019) was held at the China National Convention Center on May 19-24, 2019. The series of the ND conferences are the largest conferences in nuclear data research field that are held every three years. In this paper, as a part of the conference reports of ND2019, the authors gave summaries of the presentations on nuclear data evaluation and theory conducted at the conference.
Ekawa, Hiroyuki; Ashikaga, Sakiko; Hasegawa, Shoichi; Hashimoto, Tadashi; Hayakawa, Shuhei; Hosomi, Kenji; Ichikawa, Yudai; Imai, Kenichi; Kimbara, Shinji*; Nanamura, Takuya; et al.
Progress of Theoretical and Experimental Physics (Internet), 2019(2), p.021D02_1 - 021D02_11, 2019/02
Times Cited Count：25 Percentile：83.41(Physics, Multidisciplinary)Kofu, Maiko; Hashimoto, Naoki*; Akiba, Hiroshi*; Kobayashi, Hirokazu*; Kitagawa, Hiroshi*; Iida, Kazuki*; Nakamura, Mitsutaka; Yamamuro, Osamu*
Physical Review B, 96(5), p.054304_1 - 054304_7, 2017/08
Times Cited Count：15 Percentile：57.94(Materials Science, Multidisciplinary)The vibrational states of hydrogen atoms in bulk and nanocrystalline palladium were examined in a wide energy region 
meV using neutron spectroscopy. In bulk PdH
, the vibrational excitations of H atoms were roughly reproduced by the quantum harmonic oscillator (QHO) model. In PdH
nanocrystals with a diameter of 8 nm, however, additional vibrational excitations were found at energies above 80 meV. The energies and intensities of the additional states were not explained by QHO but reasonably described as vibrations in a highly anharmonic trumpet-like potential. The additional excitations are attributed to the vibrations of H atoms at tetrahedral sites in the subsurface region stabilized by surface effects. This is an experimental work which clearly detects hydrogen vibration 
metal nanoparticles.
-ray beamsHayakawa, Takehito; Miyamoto, Shuji*; Hajima, Ryoichi; Shizuma, Toshiyuki; Amano, So*; Hashimoto, Satoshi*; Misawa, Tsuyoshi*
Journal of Nuclear Science and Technology, 53(12), p.2064 - 2071, 2016/12
Times Cited Count：6 Percentile：43.12(Nuclear Science & Technology)We have proposed a new selective isotope transmutation method using photonuclear reactions with quasi-monochromatic -ray beams. This method is based on the fact that the particle threshold of a long-lived fission product (LLFP) such as 
Zr, 
Pd, or 
Se is lower than those of stable isotopes of the same chemical element. Therefore, this method has an excellent advantage that LLFPs cannot, in principle, be produced newly even if the target materials include stable isotopes in addition to a LLFP. Laser Compton scattering -ray sources and neutron capture -rays in nuclear reactors are candidates for this method.
COgawa, Tatsuhiko; Sato, Tatsuhiko; Hashimoto, Shintaro; Satoh, Daiki; Tsuda, Shuichi; Niita, Koji*
Physical Review C, 92(2), p.024614_1 - 024614_14, 2015/08
Times Cited Count：45 Percentile：93.39(Physics, Nuclear)For prediction of radiological impact of heavy ions in accelerator facilities, space missions and cancer therapy, nuclear reaction models play a fundamental role. As one of such models, JAERI Quantum molecular dynamics (JQMD) has been successfully used to describe production of residue and secondary particles in nucleus-nucleus collisions. However, it has been pinpointed that JQMD underestimates projectile-like fragments produced in peripheral collisions. Moreover, no cross section data systematically measured over a wide energy range are not available, which makes it difficult to benchmark the reaction models. In this study, we develop a method to measured fragmentation cross sections using a thick target and detecting fragments produced from incident ions fragmented in the target using telescope detectors. Thus we obtained fragmentation cross sections systematically over a wide energy range. We also revise the description of reaction mechanism and ground-state nuclear structure in JQMD to take into account for peripheral collisions accurately. So far, ground-state nuclei got excited and sometimes disintegrated owing to frame transform from the laboratory system to the center-of-mass system. Fragment production cross sections calculated by the revised JQMD (JQMD2.0) are in better agreement with the literature data.
Li(
,
) reactionsHashimoto, Shintaro; Iwamoto, Osamu; Iwamoto, Yosuke; Sato, Tatsuhiko; Niita, Koji*
Energy Procedia, 71, p.191 - 196, 2015/05
Times Cited Count：4 Percentile：93.1(Energy & Fuels)Accelerator-based neutron sources using proton- and deuteron-induced reactions have been utilized for scientific and medical applications, such as irradiation testing of fusion reactor materials at IFMIF and BNCT. Quasi-monoenergetic neutron beams using Li(,)Be are of special importance for calibrating a detector and measuring cross sections for neutron induced reactions. PHITS can deal with the transport of incident protons as well as secondary neutrons using various physics models, and it can estimate particle fluxes in the beam line and energy deposition in shielding materials. Therefore, PHITS is a useful code for neutron source design in accelerator facilities. However, nuclear reaction models implemented in PHITS, such as INC, were not enough to reproduce the peak structure in neutron spectra of experimental data, since these models do not consider the transition process of Li(,)Be. We have developed a new option that adds peaks obtained by the DWBA method, which gives cross sections of the transition on the basis of quantum mechanics, to results calculated by the INC model. We had applied this option to estimate neutron spectra in the reactions at incident energies below 50 MeV. Results of the INC model using the option had been in good agreement with experimental data. In this study, we extended the applicable incident energy range up to 400 MeV for the Li(,
) reactions. We will show the comparison between the calculated result and experimental data, and discuss the validity of the option for the reactions.
Makhsun*; Hashimoto, Takuya*; Sakuma, Takashi*; Takahashi, Haruyuki*; Kamishima, Osamu*; Igawa, Naoki; Danilkin, S. A.*
Journal of the Physical Society of Japan, 83(7), p.074602_1 - 074602_4, 2014/07
Times Cited Count：2 Percentile：20.34(Physics, Multidisciplinary)The correlations of atomic thermal displacements in Al were obtained from the analysis of diffuse neutron scattering intensity. The interatomic force constants were determined from the correlation effects using a newly introduced equation. The derived force constants and the crystal structure of Al were used to estimate the phonon dispersion relations, phonon density of states, and specific heat by computer simulation. The calculated phonon dispersion relations and specific heat of Al are similar to those obtained from inelastic neutron scattering and specific heat measurements, respectively.
Yamamoto, Tsuyoshi; Hashimoto, Yasunori*; Serizawa, Yasunori*; Inamoto, Shuji*; Sato, Kazuyoshi; Sugie, Tatsuo; Takeuchi, Masaki; Kawano, Yasunori
Fusion Engineering and Design, 89(5), p.532 - 535, 2014/05
Times Cited Count：1 Percentile：8.82(Nuclear Science & Technology)The diagnostic systems are essential for the plasma control and physics understandings. JAEA has proposed the new concept of supervisory system which manages operation sequences, current state and configuration parameters for the measurement based on our experiences in operating plasma diagnostic systems. We designed the supervisory system satisfying the requirements from both CODAC system and diagnostic systems. In our design, the tool which converts operational steps described as flowcharts into EPICS Records templates is introduced. This tool will ensure reduction of the system designers' efforts. We also designed the sequencing simulator that can submit transition commands internally instead of CODAC system for the calibration and commissioning. The mechanism which changes the limit values and consistency check algorithms in accordance with the conditions of the diagnostics system is also proposed.
Hashimoto, Shintaro; Iwamoto, Osamu; Iwamoto, Yosuke; Sato, Tatsuhiko; Niita, Koji*
Nuclear Data Sheets, 118, p.258 - 261, 2014/05
Times Cited Count：5 Percentile：37.93(Physics, Nuclear)Particle transport simulation codes based on the Monte Carlo technique are utilized to predict interaction of radiations with materials. The codes describe the transport of all particles, e.g. photons, electrons, nucleons, and heavy ions by various models for physical processes and nuclear reaction. In particular, nuclear reaction processes are essential parts for the accurate prediction. Recently, accelerator-based neutron sources using proton or deuteron beams with energies from 10 to 100 MeV come to be utilized for scientific and medical applications. For neutron source design, accurate description of neutron yields created by nuclear reactions is required in the simulation. However, the Intra-Nuclear Cascade type models used in most of the simulation codes are not enough to reproduce experimental data because of neglecting quantum mechanical effects. In this study, we combined the cascade type models and an event generator using the DWBA (Distorted Wave Born Approximation) calculation, which is a theoretical model based on quantum mechanics. We verified that the calculated results with the combination model can reproduce experimental data of neutron spectra in deuteron-induced reactions. We will also present the validity of the combination model for proton-induced reactions.
Nagai, Yasuki; Hashimoto, Kazuyuki; Hatsukawa, Yuichi; Saeki, Hideya; Motoishi, Shoji; Sonoda, Nozomi; Kawabata, Masako; Harada, Hideo; Kin, Tadahiro*; Tsukada, Kazuaki; et al.
Journal of the Physical Society of Japan, 82(6), p.064201_1 - 064201_7, 2013/06
Times Cited Count：43 Percentile：85.32(Physics, Multidisciplinary)Oshima, Takeshi; Deki, Manato; Makino, Takahiro; Iwamoto, Naoya; Onoda, Shinobu; Hirao, Toshio*; Kojima, Kazutoshi*; Tomita, Takuro*; Matsuo, Shigeki*; Hashimoto, Shuichi*
AIP Conference Proceedings 1525, p.654 - 658, 2013/04
Times Cited Count：0 Percentile：0.05(Physics, Applied)Metal-Oxide-Semiconductor (MOS) capacitors were fabricated on n-type 4H-SiC epitaxial layers, and the leakage current through the gate oxide during heavy ion irradiation was investigated in order to evaluate dielectric breakdown induced by heavy ions (Single Event Gate Rupture: SEGR). The gate oxide at thickness ranges between 60 and 80 nm was formed using pyrogenic oxidation at 1100 
C for 60 min. Circular electrodes with 180 
diameter were formed using Al evaporation and a lift-off technique. The leakage current observed through the gate oxide was monitored during 18 MeV oxygen (O) or nickel (Ni) ions. As a result, although no significant difference in the value of the electric field at the dielectric breakdown (around 8.2 MV/cm) was observed between non-irradiated and 18 MeV-O irradiated samples, the value decreased to be 7.3 MV/cm in the case of 18 MeV-Ni ion incidence. The Linier Energy Transfer (LET) for 18 MeV-O is 7 MeV cm
/mg, and this value is smaller than that for 18 MeV-Ni (24 MeV cm/mg). Also, 18 MeV-Ni ions deposit energy in narrower regions than 18 MeV-O ions. Thus, it can be concluded that the high density of charge induced by 18 MeV-Ni ions triggers SEGR in SiC MOS capacitors.
Deki, Manato; Makino, Takahiro; Tomita, Takuro*; Hashimoto, Shuichi*; Kojima, Kazutoshi*; Oshima, Takeshi
Proceedings of 10th International Workshop on Radiation Effects on Semiconductor Devices for Space Applications (RASEDA-10) (Internet), p.78 - 81, 2012/12
Metal-Oxide-Semiconductor (MOS) capacitors fabricated on Silicon Carbide (SiC) under applied biases were irradiated with heavy ions. The relationship between critical electric field (E
) and Linear Energy Transfer (LET) was investigated. As a results of 9 MeV-Ni, 18 MeV-Ni, Kr-322 MeV and 454 MeV-Xeirradiation (the values of LET are 14.6, 23.8, 42.2 and 73.2 MeV cm/mg, respectively), reciprocal value of E increases with increasing LET. The similar relationship was also reported Si MOS capacitors. However, the increase in SiC MOS capacitors is smaller than that in Si ones because the generation energy of one electron-hole pair for SiC is larger than that for Si.
superstructureFukaya, Yuki; Matsuda, Iwao*; Hashimoto, Mie*; Kubo, Keisuke*; Hirahara, Toru*; Yamazaki, Shiro*; Choi, W. H.*; Yeom, H. W.*; Hasegawa, Shuji*; Kawasuso, Atsuo; et al.
Surface Science, 606(11-12), p.919 - 923, 2012/06
Times Cited Count：6 Percentile：28.18(Chemistry, Physical)no abstracts in English
Hatsukawa, Yuichi; Nagai, Yasuki; Kin, Tadahiro; Segawa, Mariko; Harada, Hideo; Iwamoto, Osamu; Iwamoto, Nobuyuki; Ochiai, Kentaro; Takakura, Kosuke; Konno, Chikara; et al.
Proceedings in Radiochemistry, 1(1), p.327 - 329, 2011/09
Authors proposed a new route to produce 
Mo by the 
Mo(,2)Mo reaction, which has some characteristic features. Such as the reaction cross section is large, about 1.5 barn at 12 
17 MeV, which is 10 times larger than the thermal-neutron capture cross section of 
Mo. Second, the cross sections of the (,
), (,
), and (,) reactions are less than a few mb at = 14 MeV. Third, a large amount of Mo target materials can be used, compared to that for proton beam irradiation on Mo. Fourth, intense neutrons with energy of 12-17 MeV are already available. In the present work we have measured all -rays emitted from activities produced by bombarding a natural Mo target with neutrons from the D(
H,)
He reaction at Fusion Neutronics Source Facility (FNS) at Japan Atomic Energy Agency (JAEA) to study characteristic features mentioned above more in detail. The neutron flux was about 10n/cm
s. The experimental results at FNS will be discussed in the conference.
Ito, Takuto*; Deki, Manato; Tomita, Takuro*; Matsuo, Shigeki*; Hashimoto, Shuichi*; Kitada, Takahiro*; Isu, Toshiro*; Onoda, Shinobu; Oshima, Takeshi
Proceedings of 12th International Symposium on Laser Precision Microfabrication (LPM 2011) (Internet), 5 Pages, 2011/06
Deki, Manato; Ito, Takuto*; Yamamoto, Minoru*; Tomita, Takuro*; Matsuo, Shigeki*; Hashimoto, Shuichi*; Kitada, Takahiro*; Isu, Toshiro*; Onoda, Shinobu; Oshima, Takeshi
Applied Physics Letters, 98(13), p.133104_1 - 133104_3, 2011/03
Times Cited Count：13 Percentile：49.06(Physics, Applied)Matsuda, Iwao*; Nakamura, Fumitaka*; Kubo, Keisuke*; Hirahara, Toru*; Yamazaki, Shiro*; Choi, W. H.*; Yeom, H. W.*; Narita, Hisashi*; Fukaya, Yuki; Hashimoto, Mie*; et al.
Physical Review B, 82(16), p.165330_1 - 165330_6, 2010/10
Times Cited Count：9 Percentile：40.54(Materials Science, Multidisciplinary)no abstracts in English
