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Probing the Nuclear Equation of State in the quasi-elastic nucleus-nucleus scattering

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 نشر من قبل Dao Tien Khoa
 تاريخ النشر 2005
  مجال البحث
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Large-angle elastic scattering of alpha-particle and strongly-bound light nuclei at a few tens MeV/nucleon has shown the pattern of rainbow scattering. This interesting process was shown to involve a significant overlap of the two colliding nuclei, with the total nuclear density well above the saturation density of normal nuclear matter (NM). For a microscopic calculation of the nucleus-nucleus potential within the folding model, we have developed a density dependent nucleon-nucleon (NN) interaction based on the G-matrix interaction M3Y. Our folding analysis of the refractive 4He, 12C, and 16O elastic scattering shows consistently that the NM incompressibility K should be around 250 MeV which implies a rather soft nuclear Equation of State (EOS). To probe the symmetry part of the nuclear EOS, we have used the isovector coupling to link the isospin dependence of the proton optical potential to the cross section of (p,n) charge-exchange reactions exciting the isobaric analog states in nuclei of different mass regions. With the isospin dependence of the NN interaction fine tuned to reproduce the charge exchange data, a realistic estimate of the NM symmetry energy has been made.



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