Stellar stability in the presence of reacting interfaces: consequences for hybrid stars

Abstract

If the surface tension of dense matter is high enough, a hybrid star composed of a quark matter core and a hadronic mantle may display a sharp interface. Perturbations of such a star may lead to conversion reactions occurring in the vicinity of the quark-hadron splitting surface. If the conversion timescale is much larger than the perturbation one (slow reactions), changes of stellar stability do occur at critical points of the M(R) curve. As a consequence, a new class of dynamically stable hybrid stars is possible. Densities tens of times larger than the nuclear saturation density could be attained at the center of these hypothetic objects. We examine possible formation mechanisms for this new class of hybrid configurations and explore potential observational signatures that could serve as evidence for their existence.