Speaker
Description
We perform a comprehensive Bayesian analysis to constrain the neutron star (NS) equation
of state (EoS) using a wide range of terrestrial and astrophysical data. The terrestrial inputs
include quantities related to symmetric nuclear matter (SNM) and symmetry energy up to two
times saturation density (ρ0 ≃ 0.16 fm−3
), derived from finite nuclei and HIC. The astrophysical
constraints incorporate NS radii and tidal deformabilities from recent NICER observations and
GW170817, respectively. We consider five different EoS models: Taylor, n/3, Skyrme, RMF, and
sound speed (CS), and analyze them by sequentially updating the priors with (i) χEFT-based pure
neutron matter, (ii) terrestrial, empirical and earlier astrophysical data, (iii) case (ii) including
NICER radii of PSR J0437+4715 and J0614+3329, (iv) all data combined, and (v) excluding
empirical nuclear inputs. We also perform Bayesian model comparison which favors the Skyrme
model under all combined data [scenario (iv)], yielding tight constraints on symmetry energy
parameters: L0 = 56 ± 3 MeV, Ksym0 = −132 ± 15 MeV and also on SNM parameters:
K0 = 265 ± 12 MeV and Q0 = −366 ± 43 MeV. The mass-radius and mass-tidal deformability
posterior distributions are also well constrained. The radius and tidal deformability of a 1.4 M⊙
neutron star are found to be R1.4 = 11.85 ± 0.11 km and Λ1.4 = 354 ± 25, respectively
