Speaker
Description
Precise measurements of neutron-star masses and radii by the NICER mission offer important insights into the nature of dense matter and the equation of state. We performed a Bayesian hypothesis-ranking analysis for equation of state model selection in light of the latest NICER measurements, including the recent measurement of PSR J0614-3329, which reported an equatorial radius of 10.29 km for a mass of 1.44 solar masses. For this, we considered a wide range of neutron-star and strange-quark-star models, constructed from realistic phenomenological and microscopic approaches. We found substantial evidence favouring strange quark stars over physically motivated neutron-star models compatible with the small estimated radius. This conclusion was further strengthened by a full Bayesian model-selection analysis comparing phenomenological models of neutron stars against strange quark stars. Our results provide strong support for the presence of quark matter in compact stars and for the possible existence of strange quark stars, as predicted by the Bodmer–Witten hypothesis, suggesting that they should be considered among the compact-star population in astrophysical data analyses. Future multimessenger observations with improved precision are expected to provide deeper insights into the interior composition of compact stars.