paper

Extracting the nuclear symmetry potential and energy from neutron-nucleus scattering data

arXiv:1301.3256 · doi:10.1016/j.physletb.2013.03.005

Abstract

According to the Hugenholtz-Van Hove theorem, the symmetry energy and its density slope can be decomposed uniquely in terms of the single-nucleon potential in asymmetric nuclear matter which, at normal density, can be constrained by the nucleon optical model potential extracted from analyzing the nucleon-nucleus scattering data. To more accurately extract information on the symmetry energy and its density slope at normal density from neutron-nucleus scattering data, going beyond the well-known Lane potential, we include consistently the second order terms in isospin asymmetry in both the optical model potential and the symmetry energy decomposition. We find that the strength of the second-order symmetry potential $U_{sy m, 2}$ in asymmetric nuclear matter is significant compared to the first-order one U_{sym,1} $, es p ec ia l l y a t hi g hn u c l eo nm o m e n t u m . W hi l e t h e$ U_{sym,1} $a t n or ma l d e n s i t y d ecr e a ses w i t hn u c l eo nm o m e n t u m, t h e$ U_{sym,2} $i s f o u n d t o ha v e t h eo pp os i t e b e ha v i or . M or eo v er, w e d i sc u sse f f ec t so f t h e$ U_{sym,1} $an d$ U_{sym,2} $o n d e t er minin g t h e d e n s i t y d e p e n d e n ceo f t h esy mm e t r y e n er g y, an d w e f in d t ha tt h e a v ai l ab l e n e u t r o n - n u c l e u ssc a tt er in g d a t a f a v or a so f t er d e n s i t y d e p e n d e n ceo f t h esy mm e t r y e n er g y a t n or ma l d e n s i t y w i t han e g l i g ib l eco n t r ib u t i o n f r o m t h e$ U_{sym,2}$.

7 pages, 4 figures, 2 tables. Discussions and 1 table added. Accepted version to appear in PLB