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arXiv · 0904.0548

Low-lying magnetic excitations of doubly-closed-shell nuclei and nucleon-nucleon effective interactions

V. De Donno·G. Co'·C. Maieron·M. Anguiano·A. M. Lallena·M. Moreno Torres
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Abstract

We have studied the low lying magnetic spectra of 12C, 16O, 40Ca, 48Ca and 208Pb nuclei within the Random Phase Approximation (RPA) theory, finding that the description of low-lying magnetic states of doubly-closed-shell nuclei imposes severe constraints on the spin and tensor terms of the nucleon-nucleon effective interaction. We have first made an investigation by using four phenomenological effective interactions and we have obtained good agreement with the experimental magnetic spectra, and, to a lesser extent, with the electron scattering responses. Then we have made self-consistent RPA calculations to test the validity of the finite-range D1 Gogny interaction. For all the nuclei under study we have found that this interaction inverts the energies of all the magnetic states forming isospin doublets.

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V. De Donno, G. Co', C. Maieron, M. Anguiano, A. M. Lallena, M. Moreno Torres. 2009-04-03. Low-lying magnetic excitations of doubly-closed-shell nuclei and nucleon-nucleon effective interactions. https://doi.org/10.1103/physrevc.79.044311

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