Speaker
Description
The composition of the core of neutron stars is still under debate. Agnostic descriptions of the equation of state are a powerful tool to determine the allowed region in the pressure-energy density or mass-radius space defined by observations and theoretical ab-initio calculations. These methods, however, cannot really give information on the neutron star composition. Understanding the microphysics that spans the regions determined by agnostic descriptions is, therefore, necessary. In particular, we are interested in identifying signatures of the onset of exotic degrees of freedom or quark matter. It is expected that the next generation of gravitational wave and electromagnetic detectors will allow the determination of the neutron star radius and mass with a small uncertainty, which will have an important impact on the information that can be extracted about the high density equation of state of baryonic matter.
Microscopic models are used to describe the different phases of matter, including relativistic mean field models, chiral symmetric models, and quark models. Given a set of constraints, Bayesian inference will be used to determine the model parameters. As constraints , we consider nuclear matter properties, neutron star observations and theoretical ab-initio calculations at low and high density. The dependence on the priors, on the constraints and on the choice of the likelihoods will be discussed. Within these microscopic models, the properties of neutron stars and nuclear matter are discussed taking into account the constraints that have been imposed. The effect of considering different compositions of matter will also be discussed.
