New Result in the Production and Decay of an Isotope, (278)113, of the 113th Element

作者：Morita, Kosuke^*; Morimoto, Kouji; Kaji, Daiya; Haba, Hiromitsu; Ozeki, Kazutaka; Kudou, Yuki; Sumita, Takayuki; Wakabayashi, Yasuo; Yoneda, Akira; Tanaka, Kengo; Yamaki, Sayaka; Sakai, Ryutaro; Akiyama, Takahiro; Goto, Shin-ichi; Hasebe, Hiroo; Huang, Minghui; Huang, Tianheng; Ideguchi, Eiji; Kasamatsu, Yoshitaka; Katori, Kenji; Kariya, Yoshiki; Kikunaga, Hidetoshi; Koura, Hiroyuki; Kudo, Hisaaki; Mashiko, Akihiro; Mayama, Keita; Mitsuoka, Shin-ichi; Moriya, Toru; Murakami, Masashi

来源：Journal of the Physical Society of Japan, 2012, 81(10): 103201.

DOI：10.1143/JPSJ.81.103201

• new element 113
• gas-filled recoil ion separator
• alpha-decay chain

An isotope of the 113th element, i.e., (278)113, was produced in a nuclear reaction with a Zn-70 beam on a Bi-209 target. We observed six consecutive alpha-decays following the implantation of a heavy particle in nearly the same position in the semiconductor detector under an extremely low background condition. The fifth and sixth decays are fully consistent with the sequential decays of (262)Db and Lr-258 in both decay energies and decay times. This indicates that the present decay chain consisted of (278)113, (274)Rg (Z = 111), (270)Mt (Z = 109), (266)Bh (Z = 107), (262)Db (Z = 105), and Lr-258 (Z = 103) with firm connections. This result, together with previously reported results from 2004 and 2007, conclusively leads to the unambiguous production and identification of the isotope (278)113 of the 113th element.

• 出版日期2012-10
• 单位中国科学院近代物理研究所; RIKEN