Speaker
Description
We obtain a empirical relation for the neutron star maximum mass arising from a particular
combination of the saturation density (n0), the effective mass (m∗), and (when present) the vector
meson self-coupling constant (ζ) within the relativistic mean-field model framework. Observations
of massive neutron stars heavier than ∼ 2M⊙ have eliminated the softest equation of state from
consideration and impose strong constraints on nuclear interactions used to model dense nuclear
matter. To date, numerous efforts have been made to refine relativistic mean-field models through
the inclusion of additional mesons, such as the δ meson, as well as through the introduction of
additional couplings. We show that current RMF models, including our own constructions, exhibit
a maximum neutron star mass that is primarily determined by the combination of the saturation
density, the effective mass at saturation, and the vector meson self-coupling constant. When con-
straining the pure neutron matter equation of state using chiral effective field theory (ChEFT) at
low densities, 250 parameter sets were generated to derive an empirical formula for the maximum
mass of neutron stars and apply the formula with the present relativistic mean field models.