-clustering in atomic nuclei from first principles with statistical learning and the Hoyle state character

Otsuka, Takaharu; Abe, Takashi*; Yoshida, Toru*; Tsunoda, Yusuke*; Shimizu, Noritaka*; Itagaki, Naoyuki*; Utsuno, Yutaka; Vary, J. P.*; Maris, P.*; Ueno, Hideki*

Nature Communications (Internet), 13, p.2234_1 - 2234_10, 2022/04

https://doi.org/10.1038/s41467-022-29582-0

no abstracts in English

High-precision quadrupole moment reveals significant intruder component in Al ground state

Heylen, H.*; De Rydt, M.*; Neyens, G.*; Bissell, M. L.*; Caceres, L.*; Chevrier, R.*; Daugas, J. M.*; Ichikawa, Yuichi*; Ishibashi, Yoko*; Kamalou, O.*; et al.

Physical Review C, 94(3), p.034312_1 - 034312_5, 2016/09

AA2016-0115.pdf:0.4MB

https://doi.org/10.1103/PhysRevC.94.034312

no abstracts in English

Nanoscale diffusion tracing by radioactive Li tracer

Ishiyama, Hironobu*; Jeong, S.-C.*; Watanabe, Yutaka*; Hirayama, Yoshikazu*; Imai, Nobuaki*; Miyatake, Hiroari*; Oyaizu, Mitsuhiro*; Katayama, Ichiro*; Osa, Akihiko; Otokawa, Yoshinori; et al.

Japanese Journal of Applied Physics, 53(11), p.110303_1 - 110303_4, 2014/11

https://doi.org/10.7567/JJAP.53.110303

Precision measurement of the electric quadrupole moment of Al and determination of the effective proton charge in the sd-shell

De Rydt, M.*; Neyens, G.*; Asahi, Koichiro*; Balabanski, D. L.*; Daugas, J. M.*; Depuydt, M.*; Gaudefroy, L.*; Grvy, S.*; Hasama, Yuka*; Ichikawa, Yuichi*; et al.

Physics Letters B, 678(4), p.344 - 349, 2009/07

https://doi.org/10.1016/j.physletb.2009.06.043

no abstracts in English

Application of archaeological analogues for a repository safety case; Arguments supporting the waste container lifetime

Yoshikawa, Hideki; Ueno, Kenichi; Yui, Mikazu

Proceedings of Safety Cases for Deep Geological Disposal of Radioactive Waste; Where do we stand ?, p.365 - 371, 2008/00

In the Japanese HLW safety case, a carbon steel container (overpack) was designed with a 1000 year lifetime, based on a corrosion allowance of 40 mm derived from laboratory data obtained under anaerobic conditions. Analogue studies have been conducted to increase confidence in the robustness of this design basis. Using X-ray computer tomography (X-CT) to measure corrosion rate, about 40 samples of iron archaeological artifacts, which were found at Japanese ancient monuments after burial underground for a few hundred to one thousand years, were analyzed. The their corrosion rates are more than one order of magnitude less than the design allowance of 40 mm / ka, which supports the argument that the designed corrosion allowance is conservative.

RF property of the prototype cryomodule for ADS superconducting linac

Kako, Eiji*; Noguchi, Shuichi*; Ouchi, Norihito*; Shishido, Toshio*; Akaoka, Nobuo*; Kobayashi, Hideki*; Ouchi, Nobuo; Ueno, Tomoaki*; Hara, Hiroshi*; Matsuoka, Masanori*; et al.

Proceedings of 9th European Particle Accelerator Conference (EPAC 2004) (CD-ROM), p.1042 - 1044, 2004/07

no abstracts in English

Fundamental Study on HLW Glass Dissolution in Highly Alkaline Solution

Hayashi, Maki*; Ueno, Kenichi; Yoshikawa, Hideki; Yui, Mikazu

JNC TN8400 2003-029, 33 Pages, 2003/11

JNC-TN8400-2003-029.pdf:3.55MB

The purpose of this study is to understand, experimentaly and analytically, the alteration-phase formation and associated elemetal release during aqueous corrosion of HLW glass in order to establish the evaluation and modeling of a more realistic long-term exudation action in disposal environment. Static deterioration tests were performed with a simulated HLW glass, P0798 glass, in solution pH is fixed on conditions (pH = 11) and Na concentration is changed, the dissolution of glass and mineralization and the influence of Na concentration exerted on Cs exudation were evaluated. The solution concentrations of dissolved elements were measured by use of ICP-AAS, ICP-AES, ICP-MS, and the unreacted glass and reacted glass were analyzed by use of XRD and BET , electron microscope (SEM/EDS). The results indicated that; 1) Na-beidellite may generate in this experiment condition, 2) The glass dissolution proceeds in proportion to square root of time , it turns out that it is not dependent on Na concentration in solution on this experiment conditions, 3) Most of Cs in the glass is involved with the crystalline alteration-phases formation on the surface of glass.

Analysis of the Excavated Archaeological Iron Using X-ray-CT as Natural Analogue

Yoshikawa, Hideki; Ueno, Kenichi; ; Honda, Takashi*;

9th International Conference on Environmental Remediation Ra, 0 Pages, 2003/00

None

Electric quadrupole moment measurement using a new RF-application system

Nagae, Daisuke; Takemuara, Makoto*; Ueno, Hideki*; Kameda, Daisuke*; Asahi, Koichiro*; Yoshimi, Akihiro*; Sugimoto, Takashi*; Nagatomo, Takashi*; Kobayashi, Yoshio*; Uchida, Makoto*; et al.

no journal, , 

An electric quadrupole moment ( moment) is sensitive to collective aspects of nuclear structure. In the -moment measurement for unstable nuclei, we employ the -detected nuclear-quadrupole resonance method. In this method, we need to supply resonance frequencies, where denotes the nuclear spin. We have developed a new RF-application system to induced all of the transitions. The application of the frequencies may be pursued in two different ways; the sequential RF pulse method and the mixed-wave RF pulse method. We confirmed the reversal of polarization for the both methods, from measurements of -ray asymmetry change for polarized B. Using this system, the moments of Al have been measured to be mb and mb by the sequential RF pulse method.

Handling of off-gas produced in the mercury target of spallation neutron source in J-PARC

Kai, Tetsuya; Seki, Masakazu; Ueno, Hideki; Kinoshita, Hidetaka; Otsu, Kiichi; Teshigawara, Makoto; Kogawa, Hiroyuki; Kasugai, Yoshimi

no journal, , 

Various radioactive nuclei are produced in the mercury circulation system of J-PARC spallation neutron source. It is required to minimize release of such volatile radioactivity as tritium (half-life of 12 years) and xenon-127 (half-life of 36 days) during works opening the mercury system to the atmosphere to replace a mercury target chamber, etc. Although a depuration process by helium-gas flushing is carried out to the mercury system, a disposal of large amount of produced gas would be an issue. Thus a test was performed to remove xenon-127 from the disposal gas. As a result the concentration of xenon-127 was successfully reduced down to one-hundredth after a 6-hour operation of a charcoal trap cooled by liquid-nitrogen. In addition desorption of xenon-127 was confirmed by heating the charcoal trap to 100 degree in Celsius. These test indicated that xenon-127 in off-gas can be well removed by using the cooled charcoal trap.