Quasifree neutron knockout reaction reveals a small -Orbital component in the Borromean nucleus B

Yang, Z. H.*; Kubota, Yuki*; Corsi, A.*; Yoshida, Kazuki; Sun, X.-X.*; Li, J. G.*; Kimura, Masaaki*; Michel, N.*; Ogata, Kazuyuki*; Yuan, C. X.*; et al.

Physical Review Letters, 126(8), p.082501_1 - 082501_8, 2021/02

AA2020-0819.pdf:1.29MB

https://doi.org/10.1103/PhysRevLett.126.082501

A quasifree (,) experiment was performed to study the structure of the Borromean nucleus B, which had long been considered to have a neutron halo. By analyzing the momentum distributions and exclusive cross sections, we obtained the spectroscopic factors for and orbitals, and a surprisingly small percentage of 9(2)% was determined for . Our finding of such a small component and the halo features reported in prior experiments can be explained by the deformed relativistic Hartree-Bogoliubov theory in continuum, revealing a definite but not dominant neutron halo in B. The present work gives the smallest - or -orbital component among known nuclei exhibiting halo features and implies that the dominant occupation of or orbitals is not a prerequisite for the occurrence of a neutron halo.

Analysis of the radioactivity concentrations in low-level radioactive waste generated from JPDR facilities, 3

Yasuda, Mari; Tanaka, Kiwamu; Watanabe, Koichi; Hoshi, Akiko; Tsuji, Tomoyuki; Kameo, Yutaka

JAEA-Data/Code 2014-011, 59 Pages, 2014/08

JAEA-Data-Code-2014-011.pdf:16.84MB

Simple and rapid methods to evaluate the radioactivity concentrations are required to be established for the near surface disposal of radioactive wastes generated from research facilities at Japan Atomic Energy Agency. In order to establish the methods to evaluate the radioactivity concentrations of miscellaneous solid wastes generated from research and testing reactors, we collected and analyzed samples from miscellaneous solid wastes generated by the decommissioning of JPDR (Japan Power Demonstration Reactor). In the present paper, we summarized data about the radioactivity concentrations which accumulated by the analysis.

Determination method using liquid scintillation counter for Cd in wastewater in Fukushima-1 Nuclear Power Plant

Yasuda, Mari; Nebashi, Koji*; Yonekawa, Naoki; Yasumatsu, Takuyo*; Kameo, Yutaka

Bunseki Kagaku, 63(4), p.345 - 350, 2014/04

https://doi.org/10.2116/bunsekikagaku.63.345

A simple analytical method was developed for the determination of Cd in the treated wastewater arising from Advanced Liquid Processing System (ALPS) at the Fukushima-1 Nuclear Power Plant. Cadmium in the wastewater containing sea salt was effectively purified by an anion-exchange procedure. It was found that more than 97% of Cd were recovered by the present procedure from a sample solution of 2M HCl. Since a radioactivity standard solution of Cd was difficult to purchase from venders, beta-ray counting efficiency for Cd was estimated using 99Tc and 36Cl standard solutions. Minimum detectable activity was calculated to be 0.003 Bq mL. The present analytical method would be well suited for a rapid and simple determination of Cd in wastewater treated by ALPS.

Analysis of the radioactivity concentrations in low-level radioactive waste generated from JPDR facilities

Hoshi, Akiko; Tsuji, Tomoyuki; Tanaka, Kiwamu; Yasuda, Mari; Watanabe, Koichi; Sakai, Akihiro; Kameo, Yutaka; Kogure, Hiroto; Higuchi, Hidekazu; Takahashi, Kuniaki

JAEA-Data/Code 2011-011, 31 Pages, 2011/10

JAEA-Data-Code-2011-011.pdf:1.7MB

Simple and rapid methods to evaluate the radioactivity concentrations are required to be established for the near surface disposal of radioactive wastes generated from research facilities at Japan Atomic Energy Agency. In order to establish the methods to evaluate the radioactivity concentrations of miscellaneous solid wastes generated from research and testing reactors, we collected and analyzed samples from miscellaneous solid wastes generated by the decommissioning of JPDR (Japan Power Demonstration Reactor). In the present paper, we summarized data (262 data) about the radioactivity concentrations of the 7 important nuclides (H, C, Co, Ni, Ni, Sr, Cs) which accumulated by the analysis.

Pulse neutron imaging experiments in the first year of J-PARC

Kai, Tetsuya; Harada, Masahide; Oikawa, Kenichi; Sakai, Kenji; Maekawa, Fujio; Oi, Motoki; Shinohara, Takenao; Aizawa, Kazuya; Takata, Shinichi; Arai, Masatoshi; et al.

no journal, , 

Development of imaging techniques with pulse neutrons were started using the NeutrOn Beam-line for Observation and Research Use (NOBORU) of J-PARC at December 2008. The results in the first three months, future research plans and discussions on a new imaging facility in J-PARC are shown.

Present status of a new pulsed neutron imaging instrument at J-PARC

Segawa, Mariko; Shinohara, Takenao; Kai, Tetsuya; Iikura, Hiroshi; Oi, Motoki; Oikawa, Kenichi; Harada, Masahide; Sakai, Kenji; Soyama, Kazuhiko; Aizawa, Kazuya; et al.

no journal, , 

Radiochemical analysis of waste debris and stagnant water in Fukushima-1 Nuclear Power Plant, 2; Analysis of Se-79, Tc-99, I-129, and -particle emitting nuclides

Hoshi, Akiko; Yasuda, Mari; Yonekawa, Naoki; Kajio, Masatoshi; Niiyama, Takuya; Yabuki, Koshi; Shimada, Asako; Kameo, Yutaka

no journal, , 

no abstracts in English

Development of multi-pinhole collimator for large imaging area with high spatial resolution

Hayashida, Hirotoshi; Segawa, Mariko; Yasuda, Ryo; Iikura, Hiroshi; Sakai, Takuro; Matsubayashi, Masahito

no journal, , 

Improvement of spatial resolution is common needs of users of in neutron radiography (NR) in various research fields such as materials, fuel cell, architecture, and so on. High collimator ratio (L/D) is one of the most significant factors for high spatial resolution imaging, because size of the geometric unsharpness formed on an image is inversely proportional to L/D. Small aperture collimator system is effective for increasing L/D of neutron radiography system. In case of using a small aperture system on thermal neutron radiography facility (TNRF) in JRR-3, the irradiation area is around 20 by 20mm, being not enough area to view large size samples. We develop a multi-pinhole collimator system in order to increase the visible area with high spatial resolution.

Radiochemical analysis in stagnant water in Fukushima-1 Nuclear Power Plant, 2; Analysis of Se-79, Sr-90, Tc-99

Yasuda, Mari; Watanabe, Koichi; Hoshi, Akiko; Tanaka, Kiwamu; Kameo, Yutaka; Katayama, Atsushi; Higuchi, Hidekazu

no journal, , 

Analytical methods were developed for determination of Se-79, Sr-90 and Tc-99 in stagnant water generated from Fukushima-1 Nuclear Power Plant. The recoveries of these elements were enough to determine the concentrations of Se-79, Sr-90 and Tc-99. The interference of beta emitter could not be found by beta spectrometry. The present method could be applied to stagnant water.

Radiochemical analysis of living tree collected from Fukushima-1 Nuclear Power Station

Tanaka, Kiwamu; Ueno, Takashi; Yasuda, Mari; Shimada, Asako; Hoshi, Akiko; Kameo, Yutaka

no journal, , 

no abstracts in English