The Role of the Hadron-Quark Phase Transition in Core-Collapse Supernovae

Abstract: The hadron-quark phase transition in quantum chromodyanmics has been suggested as an alternative explosion mechanism for core-collapse supernovae. We study the impact of three different hadron-quark equations of state (EoS) with first-order (DD2F_SF, STOS-B145) and second-order (CMF) phase transitions on supernova dynamics by performing 97 simulations for solar- and zero-metallicity progenitors in the range of $14\texttt{-}100\,\text{M}<em>\odot$. We find explosions only for two low-compactness models ($14 \text{M}</em>\odot$ and $16\,\text{M}<em>\odot$) with the DD2F_SF EoS, both with low explosion energies of $\mathord{\sim}10<sup>{50}\,\mathrm{erg}$. These weak explosions are characterised by a neutrino signal with several mini-bursts in the explosion phase due to complex reverse shock dynamics, in addition to the typical second neutrino burst for phase-transition driven explosions. The nucleosynthesis shows significant overproduction of nuclei such as $<sup>{90}\mathrm{Zr}$ for the $14\,\text{M}</em>\odot$ zero-metallicity model and $<sup>{94}\mathrm{Zr}$ for the $16\,\text{M}<em>\odot$ solar-metallicity model, but the overproduction factors are not large enough to place constraints on the occurrence of such explosions. Several other low-compactness models using the DD2F_SF EoS and two high-compactness models using the STOS EoS end up as failed explosions and emit a second neutrino burst. For the CMF EoS, the phase transition never leads to a second bounce and explosion. For all three EoS, inverted convection occurs deep in the core of the proto-compact star due to anomalous behaviour of thermodynamic derivatives in the mixed phase, which heats the core to entropies up to $4k</em>\text{B}/\text{baryon}$ and may have a distinctive gravitational wave signature, also for a second-order phase transition.