Refine your search:     
Report No.
 - 
Search Results: Records 1-16 displayed on this page of 16
  • 1

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

High temperature gas-cooled reactors

Takeda, Tetsuaki*; Inagaki, Yoshiyuki; Aihara, Jun; Aoki, Takeshi; Fujiwara, Yusuke; Fukaya, Yuji; Goto, Minoru; Ho, H. Q.; Iigaki, Kazuhiko; Imai, Yoshiyuki; et al.

High Temperature Gas-Cooled Reactors; JSME Series in Thermal and Nuclear Power Generation, Vol.5, 464 Pages, 2021/02

As a general overview of the research and development of a High Temperature Gas-cooled Reactor (HTGR) in JAEA, this book describes the achievements by the High Temperature Engineering Test Reactor (HTTR) on the designs, key component technologies such as fuel, reactor internals, high temperature components, etc., and operational experience such as rise-to-power tests, high temperature operation at 950$$^{circ}$$C, safety demonstration tests, etc. In addition, based on the knowledge of the HTTR, the development of designs and component technologies such as high performance fuel, helium gas turbine and hydrogen production by IS process for commercial HTGRs are described. These results are very useful for the future development of HTGRs. This book is published as one of a series of technical books on fossil fuel and nuclear energy systems by the Power Energy Systems Division of the Japan Society of Mechanical Engineers.

Journal Articles

Production of $$^{266}$$Bh in the $$^{248}$$Cm($$^{23}$$Na,5$$n$$)$$^{266}$$Bh reaction and its decay properties

Haba, Hiromitsu*; Fan, F.*; Kaji, Daiya*; Kasamatsu, Yoshitaka*; Kikunaga, Hidetoshi*; Komori, Yukiko*; Kondo, Narumi*; Kudo, Hisaaki*; Morimoto, Koji*; Morita, Kosuke*; et al.

Physical Review C, 102(2), p.024625_1 - 024625_12, 2020/08

 Times Cited Count:2 Percentile:57.67(Physics, Nuclear)

Journal Articles

Study of quasielastic barrier distributions as a step towards the synthesis of superheavy elements with hot fusion reactions

Tanaka, Taiki*; Morita, Kosuke*; Morimoto, Koji*; Kaji, Daiya*; Haba, Hiromitsu*; Boll, R. A.*; Brewer, N. T.*; Van Cleve, S.*; Dean, D. J.*; Ishizawa, Satoshi*; et al.

Physical Review Letters, 124(5), p.052502_1 - 052502_6, 2020/02

 Times Cited Count:4 Percentile:72.03(Physics, Multidisciplinary)

Journal Articles

Observation of the competing fission modes in $$^{178}$$Pt

Tsekhanovich, I.*; Andreyev, A. N.; Nishio, Katsuhisa; Denis-Petit, D.*; Hirose, Kentaro; Makii, Hiroyuki; Matheson, Z.*; Morimoto, Koji*; Morita, Kosuke*; Nazarewicz, W.*; et al.

Physics Letters B, 790, p.583 - 588, 2019/03

 Times Cited Count:18 Percentile:95.86(Astronomy & Astrophysics)

Journal Articles

First direct mass measurements of nuclides around $$Z$$ = 100 with a multireflection time-of-flight mass spectrograph

Ito, Yuta*; Schury, P.*; Wada, Michiharu*; Arai, Fumiya*; Haba, Hiromitsu*; Hirayama, Yoshikazu*; Ishizawa, Satoshi*; Kaji, Daiya*; Kimura, Sota*; Koura, Hiroyuki; et al.

Physical Review Letters, 120(15), p.152501_1 - 152501_6, 2018/04

 Times Cited Count:47 Percentile:95.52(Physics, Multidisciplinary)

Masses of $$^{246}$$Es, $$^{251}$$Fm and the transfermium nuclei $$^{249-252}$$Md, and $$^{254}$$No, produced by hot- and cold-fusion reactions, in the vicinity of the deformed $$N=152$$ neutron shell closure, have been directly measured using a multi-reflection time-of-flight mass spectrograph. The masses of $$^{246}$$Es and $$^{249,250,252}$$Md were measured for the first time. Using the masses of $$^{249,250}$$Md as anchor points for $$alpha$$ decay chains, the masses of heavier nuclei, up to $$^{261}$$Bh and $$^{266}$$Mt, were determined. These new masses were compared with theoretical global mass models and demonstrated to be in good agreement with macroscopic-microscopic models in this region. The empirical shell gap parameter $$delta_{2n}$$ derived from three isotopic masses was updated with the new masses and corroborate the existence of the deformed $$N=152$$ neutron shell closure for Md and Lr.

Journal Articles

Determination of fusion barrier distributions from quasielastic scattering cross sections towards superheavy nuclei synthesis

Tanaka, Taiki*; Narikiyo, Yoshihiro*; Morita, Kosuke*; Fujita, Kunihiro*; Kaji, Daiya*; Morimoto, Koji*; Yamaki, Sayaka*; Wakabayashi, Yasuo*; Tanaka, Kengo*; Takeyama, Mirei*; et al.

Journal of the Physical Society of Japan, 87(1), p.014201_1 - 014201_9, 2018/01

 Times Cited Count:10 Percentile:72.43(Physics, Multidisciplinary)

Excitation functions of quasielastic scattering cross sections for the $$^{48}$$Ca + $$^{208}$$Pb, $$^{50}$$Ti + $$^{208}$$Pb, and $$^{48}$$Ca + $$^{248}$$Cm reactions were successfully measured by using the gas-filled recoil-ion separator GARIS. Fusion barrier distributions were extracted from these data, and compared with the coupled-channels calculations. It was found that the peak energies of the barrier distributions for the $$^{48}$$Ca + $$^{208}$$Pb and $$^{50}$$Ti + $$^{208}$$Pb systems coincide with those of the 2n evaporation channel cross sections for the systems, while that of the $$^{48}$$Ca + $$^{248}$$Cm is located slightly below the 4n evaporation ones. This results provide us helpful information to predict the optimum beam energy to synthesize superheavy nuclei.

Journal Articles

Observation of doubly-charged ions of francium isotopes extracted from a gas cell

Schury, P.*; Wada, Michiharu*; Ito, Yuta*; Kaji, Daiya*; Haba, Hiromitsu*; Hirayama, Yoshikazu*; Kimura, Sota*; Koura, Hiroyuki; MacCormick, M.*; Miyatake, Hiroari*; et al.

Nuclear Instruments and Methods in Physics Research B, 407, p.160 - 165, 2017/06

 Times Cited Count:9 Percentile:79.25(Instruments & Instrumentation)

Various isotopes of Ac, Ra, Fr, and Rn were produced by fusion-evaporation reactions using a $$^{48}$$Ca beam. The energetic ions were stopped in and extracted from a helium gas cell. The extracted ions were identified using a multi-reflection time-of-fight mass spectrograph. In all cases, it was observed that the predominant charge state for the extracted ions, including the alkali Fr, was 2+.

Journal Articles

Study of the reaction $$^{48}$$Ca + $$^{248}$$Cm $$rightarrow$$ $$^{296}$$Lv$$^{ast}$$ at RIKEN-GARIS

Kaji, Daiya*; Morita, Kosuke*; Morimoto, Koji*; Haba, Hiromitsu*; Asai, Masato; Fujita, Kunihiro*; Gan, Z.*; Geissel, H.*; Hasebe, Hiroo*; Hofmann, S.*; et al.

Journal of the Physical Society of Japan, 86(3), p.034201_1 - 034201_7, 2017/03

 Times Cited Count:16 Percentile:79.57(Physics, Multidisciplinary)

The fusion reaction of $$^{48}$$Ca + $$^{248}$$Cm $$rightarrow$$ $$^{296}$$Lv$$^{ast}$$ was studied using the gas-filled recoil-ion separator GARIS at RIKEN. A total of seven $$alpha$$ and spontaneous-fission decay chains were observed, which would originate from the reaction products of the element 116, $$^{292}$$Lv and $$^{293}$$Lv. Decay properties observed in the chains are in good agreement with the previously published ones. However, one of the chains showed a discrepancy, indicating the new spontaneous-fission branch in $$^{285}$$Cn or the production of the new isotope $$^{294}$$Lv.

Journal Articles

First online multireflection time-of-flight mass measurements of isobar chains produced by fusion-evaporation reactions; Toward identification of superheavy elements via mass spectroscopy

Schury, P.*; Wada, Michiharu*; Ito, Yuta*; Kaji, Daiya*; Arai, Fumiya*; MacCormick, M.*; Murray, I.*; Haba, Hiromitsu*; Jeong, S.*; Kimura, Sota*; et al.

Physical Review C, 95(1), p.011305_1 - 011305_6, 2017/01

AA2016-0638.pdf:0.71MB

 Times Cited Count:33 Percentile:96.3(Physics, Nuclear)

Using a multireflection time-of-flight mass spectrograph located after a gas cell coupled with the gas-filled recoil ion separator GARIS-II, the masses of several $$alpha$$-decaying heavy nuclei were directly and precisely measured. The nuclei were produced via fusion-evaporation reactions and separated from projectilelike and targetlike particles using GARIS-II before being stopped in a helium-filled gas cell. Time-of-flight spectra for three isobar chains, $$^{204}$$Fr-$$^{204}$$Rn-$$^{204}$$At-$$^{204}$$Po, $$^{205}$$Fr- $$^{205}$$Rn-$$^{205}$$At-$$^{205}$$Po-$$^{205}$$Bi, and $$^{206}$$Fr-$$^{206}$$Rn-$$^{206}$$At, were observed. Precision atomic mass values were determined for $$^{204-206}$$Fr, $$^{204,205}$$Rn, and $$^{204,205}$$At. Identifications of $$^{205}$$Bi, $$^{204,205}$$Po, $$^{206}$$Rn, and $$^{206}$$At were made with N$$leq$$10 detected ions, representing the next step toward use of mass spectrometry to identify exceedingly low-yield species such as superheavy element ions.

Journal Articles

Evaluation of internal stress in short-carbon-fiber reinforced plastics by transmission X-ray diffraction

Shimizu, Kenichi*; Koike, Yuki*; Yamada, Taiki*; Oharada, Kazuya*; Tanaka, Keisuke*; Shobu, Takahisa

Zairyo, 65(9), p.657 - 664, 2016/09

The internal stress in crystalline thermoplastics, polyphenylene sulphide (PPS), reinforced by carbon fibers of 30 mass% was measured by the diffraction method using synchrotron with energy of 12.3 keV. The stress in the matrix was determined by the sin2psi method with side-inclination optics of transmitted X-ray diffractions. Using skin-layer strips cut parallel, perpendicular and 45 degree to the molding direction of the injection molded plates, the matrix stress was measured under the uniaxial applied stress. The experimental values were at least qualitatively agreed with the prediction derived based on micromechanics. The quantitative difference between experiment and prediction is mainly due to the neglect of the distribution of fiber orientations in the micromechanics prediction. These residual stresses were caused by the mismatch of the thermal expansion coefficient between matrix and fibers.

Journal Articles

Probing strongly correlated 4$$f$$-orbital symmetry of the ground state in Yb compounds by linear dichroism in core-level photoemission

Mori, Takeo*; Kitayama, Satoshi*; Kanai, Yuina*; Naimen, Sho*; Fujiwara, Hidenori*; Higashiya, Atsushi*; Tamasaku, Kenji*; Tanaka, Arata*; Terashima, Kensei*; Imada, Shin*; et al.

Journal of the Physical Society of Japan, 83(12), p.123702_1 - 123702_5, 2014/12

 Times Cited Count:15 Percentile:71.43(Physics, Multidisciplinary)

We show that the strongly correlated 4$$f$$-orbital symmetry of the ground state is revealed by linear dichroism in core-level photoemission spectra, as we have discovered for YbRh$$_{2}$$Si$$_{2}$$ and YbCu$$_{2}$$Si$$_{2}$$. Theoretical analysis shows us that the linear dichroism reflects the anisotropic charge distributions resulting from a crystalline electric field. We have successfully determined the ground-state 4$$f$$ symmetry for both compounds from the polarization-dependent angle resolved core-level spectra at a temperature well below the first excitation energy. The excited-state symmetry is also probed by temperature dependence of the linear dichroism where the high measurement temperatures are on the order of the crystal-field-splitting energies.

Oral presentation

Change of "effective plasma boundary" due to beta value in LHD divertor discharges

Watanabe, Kiyomasa*; Suzuki, Yasuhiro*; Yamaguchi, Taiki; Narihara, Kazumichi*; Tanaka, Kenji*; Tokuzawa, Tokihiko*; Yamada, Ichihiro*; Sakakibara, Satoru*; Morisaki, Tomohiro*; Nakajima, Noriyoshi*; et al.

no journal, , 

no abstracts in English

Oral presentation

Fission properties of $$^{258}$$Md produced in the $$^{4}$$He+$$^{254}$$Es reaction

Nishio, Katsuhisa; Hirose, Kentaro; Makii, Hiroyuki; Orlandi, R.; Kean, K. R.*; Tsukada, Kazuaki; Asai, Masato; Toyoshima, Atsushi*; Sato, Tetsuya; Ito, Yuta; et al.

no journal, , 

no abstracts in English

Oral presentation

Fission experiment using Es-254 at JAEA Tokai tandem accelerator facility

Hirose, Kentaro; Nishio, Katsuhisa; Makii, Hiroyuki; Orlandi, R.; Tsukada, Kazuaki; Asai, Masato; Sato, Tetsuya; Ito, Yuta; Suzaki, Fumi; Nagame, Yuichiro*; et al.

no journal, , 

A specific phenomenon was found in fission-fragment mass distributions for nuclides around A=258 by spontaneous fission measurements. Fm256 splits into light and heavy fragments, like uranium isotopes, making two peaks in their mass distribution, whereas a sharp single peak was found in that of Fm258 which has only two more neutrons. In order to study such a specific phenomenon more widely, we performed an experiment of the multinucleon transfer fission in the O18+Es254 reaction at JAEA Tokai tandem accelerator facility.

Oral presentation

Fission of $$^{258}$$Md produced in the $$^{4}$$He + $$^{254}$$Es reaction

Nishio, Katsuhisa; Hirose, Kentaro; Makii, Hiroyuki; Orlandi, R.; Kean, K. R.*; Tsukada, Kazuaki; Toyoshima, Atsushi*; Asai, Masato; Sato, Tetsuya; Chiela, N. M.*; et al.

no journal, , 

no abstracts in English

Oral presentation

Fission of $$^{258}$$Md produced in the $$^{4}$$He + $$^{254}$$Es reaction

Nishio, Katsuhisa; Hirose, Kentaro; Makii, Hiroyuki; Orlandi, R.; Kean, K. R.*; Tsukada, Kazuaki; Toyoshima, Atsushi*; Asai, Masato; Sato, Tetsuya; Chiela, N. M.*; et al.

no journal, , 

no abstracts in English

16 (Records 1-16 displayed on this page)
  • 1