Dark matter effects on hybrid star properties

TL;DR

This study explores how dark matter influences the structural and observable properties of hybrid stars, revealing shifts in mass-radius relations and core sizes due to dark matter interactions.

Contribution

It introduces a model where dark matter interacts with hadronic and quark matter via Higgs exchange, affecting hybrid star characteristics and observable predictions.

Findings

Dark matter shifts energy density discontinuity points.

It reduces the minimum mass of quark-core hybrid stars.

Dark matter increases the quark core radius at higher Fermi momenta.

Abstract

In the present work we investigate the effects of dark matter (DM) on hybrid star properties. We assume that dark matter is mixed with both hadronic and quark matter and interact with them through the exchange of a Higgs boson. The hybrid star properties are obtained from equations of state calculated with a Maxwell prescription. For the hadronic matter we use the NL3* parameter set and for the quark matter, the MIT bag model with a vector interaction. We see that dark matter does not influence the phase transition points (pressure and chemical potential) but shifts the discontinuity on the energy density, which ultimately reduces the minimum mass star that contains a quark core. Moreover, it changes considerably the star family mass-radius diagrams and moves the merger polarizability curves inside the confidence lines. Another interesting feature is the influence of DM in the quark core of the hybrid stars constructed. Our results show an increase of the core radius for higher values of the dark particle Fermi momentum.