Treating quarks within neutron stars

Understand

Neutron star interiors provide the opportunity to probe properties of cold dense matter in the QCD phase diagram.

• Utilizing models of dense matter in accord with nuclear systematics at nuclear densities, we investigate the compatibility of deconfined quark cores with current observational constraints on the maximum mass and tidal deformability of neutron stars.
• We explore various methods of implementing the hadron-to-quark phase transition, specifically, first-order transitions with sharp (Maxwell construction) and soft (Gibbs construction) interfaces, and smooth crossover transitions.
• We find that within the models we apply, hadronic matter has to be stiff for a first-order phase transition and soft for a crossover transition.