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arXiv · 1610.09746

Delta isobars in relativistic mean-field models with $σ$-scaled hadron masses and couplings

E. E. Kolomeitsev·K. A. Maslov·D. N. Voskresensky
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Abstract

We extend the relativistic mean-field models with hadron masses and meson-baryon coupling constants dependent on the scalar $σ$ field, studied previously to incorporate $Δ(1232)$ baryons. Available empirical information is analyzed to put constraints on the couplings of $Δ$s with meson fields. Conditions for the appearance of $Δ$s are studied. We demonstrate that with inclusion of the $Δ$s our equations of state continue to fulfill majority of known empirical constraints including the pressure-density constraint from heavy-ion collisions, the constraint on the maximum mass of the neutron stars, the direct Urca and the gravitational-baryon mass ratio constraints.

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E. E. Kolomeitsev, K. A. Maslov, D. N. Voskresensky. 2016-10-31. Delta isobars in relativistic mean-field models with $σ$-scaled hadron masses and couplings. https://doi.org/10.1016/j.nuclphysa.2017.02.004

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