Properties of the HESS J1731-347 Object as a Twin Compact Star

by David Álvarez Castillo (Institute of Nuclear Physics PAS)

Thursday 12 Jun 2025, 14:00 → 15:00 Europe/Warsaw

By consideration of the HESS J1731-347 compact object as a hybrid twin compact star, i.e., a more compact star than its hadronic twin of the same mass, its stellar properties are derived. Its conjectured that a phase transition from hadronic to deconfined quark matter is possible in the ultrahigh density environment in neutron stars. Within the scenario in which the quark-hadron phase transition is of first order, compact star twins occur under certain physical conditions, therefore the relevance of their detection.

In this presentation I will introduce dense matter equations of state for which the resulting properties of compact stars are in good agreement with state-of-the-art constraints both from laboratory experiments as well as by multi-messenger astronomy observations. Based on the low mass observation of the HESS J1731-347 compact object, the realization of an early QCD strong hadron-quark first order phase transition as implied by the considered twins is discussed. This talk is based on the paper arXiv:2504.00240.