Slowly rotating neutron stars in the nonminimal derivative coupling sector of Horndeski gravity

TL;DR

This paper constructs slowly rotating neutron star models within a specific Horndeski gravity sector, matching solutions with cosmology, and constrains model parameters using realistic equations of state and observational data.

Contribution

It introduces a new model of neutron stars in nonminimal derivative coupling Horndeski gravity and constrains its parameters with observational data.

Findings

Identified a viable model with a single free parameter.

Established upper bounds on the parameter using realistic equations of state.

Compared surface redshift and inertia with observational data.

Abstract

This work is devoted to the construction of slowly rotating neutron stars in the framework of the nonminimal derivative coupling sector of Horndeski theory. We match the large radius expansion of spherically symmetric solutions with cosmological solutions and we find that the most viable model has only one free parameter. Then, by using several tabulated and realistic equations of state, we establish numerically the upper bound for this parameter in order to construct neutron stars in the slow rotation approximation with the maximal mass observed today. We finally study the surface redshift and the inertia of these objects and compare them with known data.