Sensitivity of neutron radii in the $""sup208_{P}bnucleusandaneutronstartonucleon-$ sigma_-$ rho_ coupling corrections in relativistic mean field theory

Abstract

We study the sensitivity of the neutron skin thickness, $S$, in a ${}^{208}$Pb nucleus to the addition of nucleon-sigma-rho coupling corrections to a selection (PK1, NL3, S271, Z271) of interactions in relativistic mean field model. The PK1 and NL3 effective interactions lead to a minimum value of $S$ = 0.16 fm in comparison with the original value of $S$ = 0.28 fm. The S271 and Z271 effective interactions yield even smaller values of $S$ = 0.11 fm, which are similar to those for nonrelativistic mean field models. A precise measurement of the neutron radius, and therefore $S$, in ${}^{208}$Pb will place an important constraint on both relativistic and nonrelativistic mean field models. We also study the correlation between the radius of a 1.4 solar-mass neutron star and $S$.

40 pages 13 figures. to be published in Physical Review C