Short-range correlations effects on the deformability of neutron stars

Abstract

In the present work, we investigate the effects of short-range correlations (SRC) on the dimensionless deformability of the binary neutron system related to the GW170817 event. We implemented phenomenological SRC in a relativistic mean-field model in which the bulk parameters, namely, incompressibility (K0), effective nucleon mass ratio (m * ), symmetry energy (J) and its slope (L0), are independently controlled. Our results point out that the SRC favor the model to pass through the constraints, established by the LIGO/Virgo Collaboration, on the values of Λ1.4 and on the Λ1 × Λ2 region. We also found a clear linear correlation between Λ1.4 with K0 and L0 (increasing dependence), and with m * and J (decreasing dependence). Finally, we also obtained compatible numbers for R1.4 (model with and without SRC) in comparison with recent data from the Neutron Star Interior Composition Explorer (NICER) mission.

Neutron star tidal deformability and equation of state constraints

“…7), astronomical observations can also be used to place constraints on the relevant parameter space. In general, since GW170817 provided an upper limit on Λ, any physical effect that results in a softening of the equation of state can be consistent with the data [88,[240][241][242][243][244][245][246] As such, a strong first-order phase transition might make an equation of state model compatible with the GW170817 data, even if the hadronic part on its own is not [152,[247][248][249][250]. A number of studies have constructed models that can successfully interpret the inspiral signal from GW170817 as the coalescence of any combination of hadronic and hybrid hadronic-quark neutron stars and place corresponding constraints on the relevant model parameter space [149,247,248,[251][252][253][254][255][256][257][258][259][260].…”