What neutron stars tell about the hadron-quark phase transition: a Bayesian study

Understand

The existence of quark matter inside the heaviest neutron stars has been the topic of numerous recent studies, many of them suggesting that a phase transition to strongly interacting conformal matter inside neutron stars is feasible.

• Here we examine this hybrid star scenario using a soft and a stiff hadronic model, a constituent quark model with three quark flavours, and applying a smooth crossover transition between the two.
• Within a Bayesian framework, we study the effect of up-to-date constraints from neutron star observations on the equation-of-state parameters and various neutron star observables.
• Our results show that a pure quark core is only possible if the maximum mass of neutron stars is below $\sim2.35~M_\odot$.