[Moller] Effects of isoscalar- and isovector-scalar meson mixing on neutron star structure

[Jay Benesch]

Interesting. 

https://arxiv.org/abs/2202.08705

Effects of isoscalar- and isovector-scalar meson mixing on neutron star structure
Fan Li, Bao-Jun Cai, Ying Zhou, Lie-Wen Chen

    Based on the accurately calibrated interaction FSUGold, we show that including isovector scalar δ meson and its coupling to isoscalar scalar σ meson in the relativistic mean field (RMF) model can soften the symmetry energy Esym(n) at intermediate density while stiffen the Esym(n) at high densities. We find this new RMF model can be simultaneously compatible with (1) the constraints on the equation of state of symmetric nuclear matter at suprasaturation densities from flow data in heavy-ion collisions, (2) the neutron skin thickness of 208Pb from the PREX-II experiment, (3) the largest mass of neutron star (NS) reported so far from PSR J0740+6620, (4) the limit of Λ1.4≤580 for the dimensionless tidal deformability of the canonical 1.4M⊙ NS from the gravitational wave signal GW170817, (5) the mass-radius of PSR J0030+0451 and PSR J0740+6620 measured by NICER, and thus remove the tension between PREX-II and GW170817 observed in the conventional RMF model. 

Comments: 	7 pages, 2 figures, 2 tables
Subjects: 	Nuclear Theory (nucl-th); High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Phenomenology (hep-ph); Nuclear Experiment (nucl-ex)