Phase-Transition-Induced Collapse of Neutron Stars

The dynamics of neutron star collapse induced by phase transitions remain poorly constrained due to a limitation in fully relativistic simulations and realistic equations of state (EOS). Hybrid quark stars, composed of a deconfined quark matter core and hadronic crust, present a unique opportunity to study the behavior of ultra-dense matter under extreme conditions. We perform numerical relativity simulations of the phase-transition-induced collapse of neutron stars using the portable code AthenaK. We present results from an ongoing effort to study the dynamics of this collapse in neutron stars, considering both nonrotating and uniformly rotating neutron stars. Simulation outputs include thermodynamic and hydrodynamic quantities, enabling analysis of density evolution, remnant properties, and black hole formation, and allowing us to connect them to their resulting gravitational wave (GW) signal. These simulations aim to explore the EOS dependent dynamics of phase-transition-induced collapse, and improve modeling of extreme matter in compact objects.