Ground-state configuration of the nucleus No

Asai, Masato; Tsukada, Kazuaki; Sakama, Minoru*; Haba, Hiromitsu*; Ichikawa, Takatoshi*; Ishii, Yasuo; Toyoshima, Atsushi; Ishii, Tetsuro; Nishinaka, Ichiro; Nagame, Yuichiro; et al.

Physical Review C, 87(1), p.014332_1 - 014332_6, 2013/01

https://doi.org/10.1103/PhysRevC.87.014332

The spin-parity and neutron configuration of the ground state of No have been identified through -decay spectroscopy. The No is the nucleus with the largest neutron number whose spin-parities and single-particle configurations have ever been identified. The neutron 9/2[615] configuration was assigned to the ground state of No as well as to the 231.4 keV level in Fm. This allowed us to establish energy spacings and order of the neutron single-particle orbitals in such heaviest nuclear region. The appearance of the 9/2[615] ground state at =157 implies that the order of the neutron orbitals between the =152 and 162 deformed shell gaps should change considerably with increasing neutron number.

Introduction to plasma fusion energy

Takamura, Shuichi*; Kado, Shinichiro*; Fujii, Takashi*; Fujiyama, Hiroshi*; Takabe, Hideaki*; Adachi, Kazuo*; Morimiya, Osamu*; Fujimori, Naoji*; Watanabe, Takayuki*; Hayashi, Yasuaki*; et al.

Kara Zukai, Purazuma Enerugi No Subete, P. 164, 2007/03

no abstracts in English

Radon concentration dependence of alpha radioactivity measurement using ionized air transportation

Naito, Susumu*; Sano, Akira*; Izumi, Mikio*; Noda, Etsuo*; Hayashi, Kazuo*; Sato, Mitsuyoshi*; Suto, Osamu; Miyamoto, Yasuaki; Kondo, Shinichi*; Iinuma, Koichi*; et al.

Nuclear Science Symposium Conference Record, 2005 IEEE, Vol.1, p.495 - 499, 2005/10

An alpha radioactivity monitor (alpha-clearance monitor) is being developed to measure alpha radioactivity of uranium contaminated waste with large and complex surfaces. It uses an alpha radioactivity measurement method by collecting the air ionized by alpha particles using an air stream and by measuring its ion current. One of the major problems of the alpha-clearance monitor is the background ion current mainly by radon in atmosphere (700 fA), which is much larger than ion current of an alpha particle (several fA). It strongly influences on the detection limit of alpha radioactivity. In order to improve the detection limit, we developed a method to monitor the radon concentration inside the monitor without the additional radon detector. In addition, the influencing factors on the detection limit: ion mobility and ion recombination coefficient were measured and evaluated on various environmental conditions (temperature, humidity and aerosol density).

Effect of magnetic reconnection in CT penetration into magnetized plasmas

Suzuki, Yoshio; Hayashi, Takaya*; Kishimoto, Yasuaki

Earth Planets and Space, 53(6), p.547 - 551, 2001/06

https://doi.org/10.1186/BF03353268

no abstracts in English

Present status of research on hydrogen energy and perspective of HTGR hydrogen production system

Miyamoto, Yoshiaki; Ogawa, Masuro; Akino, Norio; Shiina, Yasuaki; Inagaki, Yoshiyuki; Shimizu, Saburo; Onuki, Kaoru; Ishiyama, Shintaro; Katanishi, Shoji; Takeda, Tetsuaki; et al.

JAERI-Review 2001-006, 147 Pages, 2001/03

JAERI-Review-2001-006.pdf:9.2MB

no abstracts in English

Tree-dimensional dynamics of a compact torus injected into magnetized plasmas II

Suzuki, Yoshio; Hayashi, Takaya*; Miyoshi, Takahiro; Kishimoto, Yasuaki; NEXT Group

Purazuma, Kaku Yugo Gakkai-Shi, 76(3), p.288 - 294, 2000/03

http://ci.nii.ac.jp/naid/110003825360

no abstracts in English

-decay half-lives of four new neutron-rich isotopes Eu and levels in Gd

Sato, Tetsuya; Asai, Masato; Osa, Akihiko; Tsukada, Kazuaki; Hayashi, Hiroaki*; Shibata, Michihiro*; Kojima, Yasuaki*; Ichikawa, Shinichi

no journal, , 

-decay half-lives of four new neutron-rich isotopes Eu produced in the proton-induced fission of U have been determined, using an on-line isotope separator at JAEA. The measured half-life values are 7.7(4) s for Eu, 4.6(7) s for Eu, 2.7(6) s for Eu and 1.7(4) s for Eu. And we determined the , energies of Gd which is most neutron-rich Gd isotope to be 69.7(1) keV and 230.5(1) keV, respectively.

Alpha- spectroscopy of N = 155 and 157 nuclei using a gas-jet transport technique

Asai, Masato; Tsukada, Kazuaki; Sakama, Minoru*; Ishii, Yasuo; Toyoshima, Atsushi; Ishii, Tetsuro; Nishinaka, Ichiro; Nagame, Yuichiro; Kasamatsu, Yoshitaka; Haba, Hiromitsu*; et al.

no journal, , 

Alpha- spectroscopy of No and Rf nuclei with the neutron number N=155 and 157 have been performed for the first time at the JAEA tandem accelerator using a gas-jet transport technique. Spin-parities and neutron single-particle configurations of ground states of these nuclei as well as excited states in their daughter nuclei have been identified. On the basis of these experimental results, energy spacings and order of neutron single-particle orbitals between N=153 and 161 were evaluated. The result implies that the order of the neutron orbitals between N=153 and 161 should be inverted between lighter nuclei around Fm and heavier ones around Hs.

-ray spectroscopy of the heaviest nuclei at JAEA tandem accelerator

Asai, Masato; Tsukada, Kazuaki; Sakama, Minoru*; Ishii, Yasuo; Toyoshima, Atsushi; Ishii, Tetsuro; Nishinaka, Ichiro; Nagame, Yuichiro; Kasamatsu, Yoshitaka; Haba, Hiromitsu*; et al.

no journal, , 

Recent results on the -ray spectroscopic studies of the heaviest nuclei at the JAEA tandem accelerator are reviewed. The nuclei No, No, and Rf studied in the present work are the heaviest and the most neutron-rich nuclei that -ray spectroscopic studies have ever been performed for. Excited-state energies, spin-parities, and single-particle configurations of those nuclei and their daughters have been established by means of - coincidence spectroscopy. The deduced energy spacings and order of neutron single-particle orbitals suggest that the higher-order deformations play an important role in level structure of the superheavy nuclei in this region.