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Nuclear Matter in Relativistic Mean Field Theory with Isovector Scalar Meson

S. Kubis·M. Kutschera
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Abstract

Relativistic mean field (RMF) theory of nuclear matter with the isovector scalar mean field corresponding to the delta-meson [a_0(980)] is studied. While the delta-meson mean field vanishes in symmetric nuclear matter, it can influence properties of asymmetric nuclear matter in neutron stars. The RMF contribution due to delta-field to the nuclear symmetry energy is negative. To fit the empirical value, E_s=30 MeV, a stronger rho-meson coupling is required than in the absence of the delta-field. The energy per particle of neutron matter is then larger at high densities than the one with no delta-field included. Also, the proton fraction of beta-stable matter increases. Splitting of proton and neutron effective masses due to the delta-field can affect transport properties of neutron star matter.

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S. Kubis, M. Kutschera. 1997-03-08. Nuclear Matter in Relativistic Mean Field Theory with Isovector Scalar Meson. https://doi.org/10.1016/s0370-2693(97)00306-7

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