2006 Fiscal Year Final Research Report Summary
Cluster molecular structure in neutron-rich nuclei
| Project/Area Number |
16540257
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Particle/Nuclear/Cosmic ray/Astro physics
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| Research Institution | The University of Tokushima |
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Principal Investigator |
NAKAYAMA Shintaro The University of Tokushima, Faculty of Integrated Arts and Sciences, Professor, 総合科学部, 教授 (70116846)
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| Co-Investigator(Kenkyū-buntansha) |
FUSHIMI Keni-chi The University of Tokushima, Faculty of Integrated Arts and Sciences, Associate Professor, 総合科学部, 助教授 (90274191)
YAMAGATA Tamio Konan University, Department.of Physics, Professor, 理工学部, 教授 (50068144)
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| Project Period (FY) |
2004 – 2006
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| Keywords | cluster / molecular resonance / (^7Li,^7Be) reaction / photodisintegration / giant dipole resonance / ^2H(γ,n) / ^4He(γ,n) |
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| Research Abstract |
We investigated isovector excitations of nuclei via the (^7Li,^7Be) charge exchange reaction at 455 MeV. A ^7Li^<3+> beam was provided from the ring cyclotron of the Research Center for Nuclear Physics, Osaka University. Our research was focused on the molecular structure in neutron-rich nuclei and the (γ,n) cross section deduced with the (^7Li,^7Be) charge exchange reaction. We got tow main results. The (^7Li,^7Be) reaction can provide the spin-flip (ΔS=1) and spin-nonflip (ΔS=0) spectra by measuring the ^7Be particle in coincidence with the 0.43-MeV γ-ray of ^7Be.
1. Tri-nucleon cluster structure in ^6He, ^6Li and ^6Be. The structure was found to be a molecular-like structure composed of tri-nucleon clusters of t and/or ^3He, which is a two-fermion system. The ^1P and ^3P resonances were assigned from the measured angular correlations of decay particles and the analysis of the spectral shape by using the Breit-Wigner formula.
2. A new approach to the photodisintegration cross section deduced with the (^7Li,^7Be) charge exchange reaction. We applied the method to the ^2H(γ,n) and ^4He(γ,n) reaction. The former showed that the (^7Li,^7Be) ΔS=1 and ΔL=0 spectrum was successfully used to deduce the distribution of the B(M1) reduced matrix elements for the photodisintegration of deuteron from the analogous B(GT) distribution. The latter showed that the (^7Li,^7Be) ΔS=0 and ΔL=1 spectrum was successfully used to deduce the El photodisintegration cross section for the giant dipole resonance in ^4He.
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Research Products
(34 results)
