1993 Fiscal Year Final Research Report Summary
Study of Exotic Nuclei via Pion Double Charge Exchange Reactions
| Project/Area Number |
03044142
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| Research Category |
Grant-in-Aid for international Scientific Research
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| Allocation Type | Single-year Grants |
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| Section | Joint Research |
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| Research Institution | National Laboratory for High Energy Physics (KEK) |
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Principal Investigator |
CHIBA Junsei National Laboratory for High Energy Physics, 物理研究部, 助教授 (50126124)
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| Co-Investigator(Kenkyū-buntansha) |
NAGAE Tomofumi Institute for Nuclear Study, The University of Tokyo, 核研, 助手 (50198298)
FUKUDA Tomokazu Institute for Nuclear Study, The University of Tokyo, 核研, 助教授 (50116092)
HASHIMOTO Osamu Institute for Nuclear Study, The University of Tokyo, 核研, 助教授 (50092292)
IEIRI Masaharu National Laboratory for High Energy Physics, 物理研究部, 助手 (50192472)
TANAKA Kazuhiro National Laboratory for High Energy Physics, 物理研究部, 助手 (90171743)
OTSUKA Takaharu Faculty of Science, The University of Tokyo, 理・物理, 助教授 (20201379)
KOBAYASHI Toshio The Institute of Physical and Chemical Research, 副主任研究員 (30186754)
NAKAI Kozi National Laboratoey for High Energy Physics, 物理研究部, 教授 (40028155)
STROTTMAN Daniel Los Alamos National Lab. (U.S.A), ロスアラモス国立研究所, 主任研究員
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| Project Period (FY) |
1991 – 1993
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| Keywords | Exotic Nuclei / ^<11>Li / Excited state / Pion double charge exchange / LAMPF / SKS Spectrometer / Giant Resonance / DELTA in Nuclei |
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| Research Abstract |
(1) In order to search for a new type of a giant resonance in a nucleus having so-called neutron halo such as ^<11>Li, we have carried out an experiment of pion double charge exchange reaction, ^<11>B(pi^-, pi^+)^<11>Li, at LAMPF at Los Alamos National Laboratory in USA. We found the first excited state of the ^<11>Li nucleus in this experiment for the first time. However, we could not reach a final conclusion about the existence of the new type of a giant resonance, primarily due to a lack of machine time.
(2) With an experiment of target fragmentations in high-energy heavy-ion reactions at Bevalac at Lawrence Berkeley Laboratory, we showed experimentally that two-neutron emission in ^8He*^6He is a two-step process via a meta-stable ^7He.
(3) At the National Laboratory for High Energy Physics (KEK), the construction of a superconducting spectrometer was completed and tested thoroughly. The spectrometer has been so far used for studies of hypernuclear spectroscopy and gave us useful and new knowledge. We had several meetings with foreign researchers to discuss possible experiments of pion double charge exchange reactions at higher energies.
(4) Coincidence Measurements of (p, n) reactions at KEK showed interesting behaviours of DELTA particle in nuclei. Especially the process of coherent pion emission has attracted much attension. A similar experiment at Saclay Laboratory in France proved our results. However both measurements were not good enough to make a final conclusion on the coherent pion emission. A new experiment with much better resolution was carried out at LAMPF in 1993 and data analysis is now under progress.
(5) Concerning theoretical studies, we have studies deeply on the nuclear structure and density distribution of both neutrons and protons of unstable nuclei.
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Research Products
(12 results)
