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Medium-mass nuclei from chiral nucleon-nucleon interactions

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 نشر من قبل Thomas Papenbrock
 تاريخ النشر 2008
  مجال البحث
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We compute the binding energies, radii, and densities for selected medium-mass nuclei within coupled-cluster theory and employ the bare chiral nucleon-nucleon interaction at order N3LO. We find rather well-converged results in model spaces consisting of 15 oscillator shells, and the doubly magic nuclei 40Ca, 48Ca, and the exotic 48Ni are underbound by about 1 MeV per nucleon within the CCSD approximation. The binding-energy difference between the mirror nuclei 48Ca and 48Ni is close to theoretical mass table evaluations. Our computation of the one-body density matrices and the corresponding natural orbitals and occupation numbers provides a first step to a microscopic foundation of the nuclear shell model.



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