arXiv:1003.3580·v1·Nuclear Theory
Constraints on the symmetry energy and on neutron skins from the pygmy resonances in 68Ni and 132Sn
Andrea Carbone (1)🇮🇹 · Gianluca Coló (1,2)🇮🇹 · Angela Bracco (1,2)🇮🇹 · Li-Gang Cao (1,2,3,4)🇮🇹 · Pier Francesco Bortignon (1,2)🇮🇹 · Franco Camera (1,2)🇮🇹 · Oliver Wieland (2) ((1) Dipartimento di Fisica, Universitá degli Studi di Milano, via Celoria 16, 20133 Milano, Italy, (2) INFN, Sezione di Milano, via Celoria 16, 20133 Milano, Italy, (3) Institute of Modern Physics, Chinese Academy of Science, Lanzhou 730000, P.R. China, (4) Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator of Lanzhou, Lanzhou 730000, P.R. China)🇮🇹
Abstract
Correlations between the behavior of the nuclear symmetry energy, the neutron skins, and the percentage of energy-weighted sum rule (EWSR) exhausted by the Pygmy Dipole Resonance (PDR) in 68Ni and 132Sn have been investigated by using different Random Phase Approximation (RPA) models for the dipole response, based on a representative set of Skyrme effective forces plus meson-exchange effective Lagrangians. A comparison with the experimental data has allowed us to constrain the value of the derivative of the symmetry energy at saturation. The neutron skin radius is deduced under this constraint.
Comments: Accepted for publication in PRC Rapid Comminication