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Sensitivity of neutron radii in the $"" sup 208_Pb nucleus and a neutron star to nucleon-$ sigma_-$ rho_ coupling corrections in relativistic mean field theory

G. Shen·J. Li·G. C. Hillhouse·J. Meng
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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 $S$.

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G. Shen, J. Li, G. C. Hillhouse, J. Meng. 2005-01-05. Sensitivity of neutron radii in the $"" sup 208_Pb nucleus and a neutron star to nucleon-$ sigma_-$ rho_ coupling corrections in relativistic mean field theory. https://doi.org/10.1103/physrevc.71.015802%2010.1103%2Fphysrevc.75.029902

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