超重元素合成研究チーム

原子番号が103を超える元素は、超アクチノイド元素または超重元素と呼ばれ、化学的な性質が詳しく研究されていない元素群です。これらの元素は天然には存在せず、人工合成によって合成され、その化学的性質や核分光学的性質が研究されます。当研究室では理研の加速器群を使い、種々の効率的な超重元素合成方法を駆使して超重元素を合成して、それらの研究を行っています。

研究テーマ

• 新超重元素の探索
• 超重元素核の核分光
• 超重元素の化学的性質の研究
• 超重元素合成機構の研究

主要論文

1. Kosuke Morita, Kouji Morimoto, Daiya Kaji, Takahiro Akiyama, Shin-ichi Goto, Hiromitsu Haba, Eiji Ideguchi, Kenji Katori, Hiriyuki Koura, Hidetoshi Kikunaga, Hisaaki Kudo, Testuya Ohnishi, Akira Ozawa, Nozomi Sato, Toshimi Suda, Keisuke Sueki, Fuyuki Tokanai, Takayuki Yamaguchi, Akira Yoneda, Atsushi Yoshida.:
   "Observation of Second Decay Chain from 278113"
   Journal of Physical Society of Japan, 76, 045001-1 -045001-2(2007).
2. Kosuke Morita, Kouji Morimoto, Daiya Kaji, Takahiro Akiyama, Shin-ichi Goto, Hiromitsu Haba, Eiji Ideguchi, Kenji Katori, Hiroyuki Koura, Hisaaki Kudo, Testuya Ohnishi, Akira Ozawa, Toshimi Suda, Keisuke Sueki, Fuyuki Tokanai, Takayuki Yamaguchi, Akira Yoneda, Atsushi Yoshida.:
   "Experiment on Synthesis of an Isotope 277112 by 208Pb + 70Zn Reaction"
   Journal of Physical Society of Japan, 76, 043201-1 -043201-5(2007).
3. Morita, K., Morimoto, K., Kaji, D., Akiyama, T., Goto, S., Haba, H., Ideguchi, E., Kanungo, R., Katori, K., Koura, H., Kudo, H., Ohnishi, T., Ozawa, A., Suda, T., Sueki, K., Xu, H., Yamaguchi, T., Yoneda, A., Yoshida, A., and Zhao, Y.-L.:
   "Experiment on the Synthesis of Element 113 in the Reaction 209Bi(70Zn,n)278113"
   Journal of Physical Society of Japan, 73, 2593-2596(2004).
4. Morita, K., Morimoto, K., Kaji, D., Haba, H., Ozeki, K., Kudou, Y., Sato, N., Sumita, T., Yoneda, A., Ichikawa, T., Fujimori, Y., Goto, S., Ideguchi, E., Kasamatsu, Y., Katori, K., Komori, Y., Koura, H., Kudo, H., Ooe, K., Ozawa, A., Tokanai, F., Tsukada, K., Yamaguchi, T., Yoshida, A.:
   "Decay Properties of 266Bh and 262Db Produced in the 248Cm + 23Na Reaction"
   Journal of Physical Society of Japan, 78 (2009) 064201.
5. Morita, K., Morimoto, K., Kaji, D., Haba, H., Ideguchi, E., Peter, J. C., Kanungo, R., Katori, K., Koura, H., Kudo, H., Ohnishi, T., Ozawa, A., Suda, T., Sueki, K., Tanihata, I., Xu, H., Yeremin, A. V., Yoneda, A., Yoshida, A., Zhao, Y.-L., Zheng, T., Goto, S., and Tokanai, F.:
   "Production and Decay Properties of 272111 and its Daughter Nuclei"
   Journal of Physical Society of Japan, 73, 1738-1744 (2004).
6. H. Haba, K. Tsukada, M. Asai, A. Toyoshima, Y. Ishii, H. Toume, T. Sato, I. Nishinaka, T. Ichikawa, S. Ichikawa, Y. Nagame, W. Sato, K. Matsuo, Y. Kitamoto, Y. Tashiro, A. Shinohara, J. Saito, M. Ito, T. Ikezawa, M. Sakamaki, S. Goto, H. Kudo, H. Kikunaga, M. Arai, S. Kamataki, A. Yokoyama, K. Akiyama, K. Sueki, Y. Oura, M. Schadel, W. Bruchle, and J. V. Kratz.:
   "Extraction Behavior of Rutherfordium into Tributylphosphate from Hydrochloric Acid"
   Radiochim. Acta 95, 1-6 (2007).
7. H. Haba, D. Kaji, H. Kikunaga, T. Akiyama, N. Sato, K. Morimoto, A. Yoneda, K. Morita, T. Takabe, and A. Shinohara.:
   "Development of Gas-jet Transport System Coupled to the RIKEN Gas-filled Recoil Ion Separator GARIS for Superheavy Element Chemistry"
   J. Nucl. Radiochem. Sci. 8, 55-58 (2007).
8. Hiromitsu Haba, Daiya Kaji, Yukiko Komori, Yuki Kudou, Kouji Morimoto, Kosuke Morita, Kazuhiro Ooe, Kazutaka Ozeki, Nozomi Sato, Atsushi Shinohara, Akira Yoneda.:
   "RIKEN Gas-filled Recoil Ion Separator (GARIS) as a Promising Interface for Superheavy Element Chemistry -Production of Element 104, 261Rf, Using the GARIS/Gas-jet System-"
   Chemistry Letters 38, 426-427(2009).
9. H. Haba et al.:
   "Production and decay properties of the 1.9-s isomeric state in 261Rf"
   Phys. Rev. C (2011) in press.
10. Ooe et al.:
    "Extraction behavior of carrier-free and macro amounts of molybdenum and tungsten from HCl solution"
    Radiochimica. Acta (2011) in press.