Self-consistent treatment of thermal effects in neutron-star
post-mergers: observational implications for third-generation
gravitational-wave detectors
We assess the impact of accurate, self-consistent modelling of thermal
effects in neutron-star merger remnants in the context of third-generation
gravitational-wave detectors. This is done through the usage, in Bayesian model
selection experiments, of numerical-relativity simulations of binary neutron
star (BNS) mergers modelled through: a) nuclear, finite-temperature (or
``tabulated'') equations of state (EoSs), and b) their simplifed piecewise (or
``hybrid'') representation. These cover four different EoSs, namely SLy4, DD2,
HShen and LS220. Our analyses make direct use of the Newman-Penrose scalar
ψ4 outputted by numerical simulations. Considering a detector network
formed by three Cosmic Explorers, we show that differences in the
gravitational-wave emission predicted by the two models are detectable with a
natural logarithmic Bayes Factor logB≥5 at average distances of
dL≃50Mpc, reaching dL≃100Mpc for source inclinations ι≤0.8, regardless of the EoS. This impact is most pronounced for the HShen
EoS. For low inclinations, only the DD2 EoS prevents the detectability of such
modelling differences at dL≃150Mpc. Our results suggest that the
usage a self-consistent treatment of thermal effects is crucial for
third-generation gravitational wave detectors.Comment: 9 pages, 3 Figure