Neutron-proton effective mass splitting in neutron-rich matter at normal density from analyzing nucleon-nucleus scattering data within an isospin dependent optical model

摘要

The neutron-proton effective $k$-mass splitting in asymmetric nucleonicmatter of isospin asymmetry $\delta$ and normal density is found to be$m^{*}_{n-p}\equiv(m^{*}_{n}-m^{*}_{p})/m=(0.41 \pm0.15)\delta$ from analyzingglobally 1088 sets of reaction and angular differential cross sections ofproton elastic scattering on 130 targets with beam energies from 0.783 MeV to200 MeV, and 1161 sets of data of neutron elastic scattering on 104 targetswith beam energies from 0.05 MeV to 200 MeV within an isospin dependentnon-relativistic optical potential model. It sets a useful reference fortesting model predictions on the momentum dependence of the nucleon isovectorpotential necessary for understanding novel structures and reactions of rareisotopes.