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Neutron Stars in Relativistic Mean Field Theory with Isovector Scalar Meson

S. Kubis·M. Kutschera·S. Stachniewicz
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Abstract

We study the equation of state of beta-stable dense matter and models of neutron stars in the relativistic mean field theory with the isovector scalar mean field corresponding to the delta-meson [a_0(980)]. A range of values of the delta-meson coupling compatible with the Bonn potentials is explored. Parameters of the model in the isovector sector are constrained to fit the nuclear symmetry energy, E_s=30 MeV. We find that the quantity most sensitive to the delta-meson coupling is the proton fraction of neutron star matter. It increases significantly in the presence of the delta-field. The energy per baryon also increases but the effect is smaller. The equation of state becomes slightly stiffer and the maximum neutron star mass increases for stronger delta-meson coupling.

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S. Kubis, M. Kutschera, S. Stachniewicz. 1998-02-24. Neutron Stars in Relativistic Mean Field Theory with Isovector Scalar Meson. https://arxiv.org/abs/astro-ph/9802303

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