# Neutron Dark Decay in Neutron Stars: The Role of the Symmetry Energy

## TL;DR

This paper explores how nuclear symmetry energy influences neutron decay into dark matter within neutron stars, considering baryon-dark matter interactions and their impact on star structure and observational consistency.

## Contribution

It extends previous models by including $eta$-stable matter and dark matter-baryon interactions, highlighting their effects on neutron star equations of state and properties.

## Key findings

- Symmetry energy critically affects neutron star matter composition.
- Dark matter interactions significantly influence neutron star structure.
- Tuning interaction parameters improves agreement with observations.

## Abstract

We conduct a systematic investigation of the influence of the nuclear symmetry energy on the proposed neutron decay into dark matter particles within the cores of neutron stars. Unlike the majority of previous studies that considered only pure neutron matter, the present analysis is extended to encompass $\beta$-stable nuclear matter. Furthermore, in relation to previous studies, the interactions between dark matter and baryons are incorporated and systematically studied regarding their effect on the structure of neutron stars. Our findings indicate that the nuclear symmetry energy plays a critical role in shaping the total equation of state (EoS) for dense neutron star matter containing dark sector components. The strength of interactions among dark matter particles, as well as between dark matter and baryons, is shown to be pivotal in determining both the composition and the macroscopic properties of neutron stars. The concurrent tuning of interaction strengths alongside the symmetry energy parameters may facilitate a more accurate reproduction of recent observational data relevant to neutron star properties. In any case, the extent to which the proposed dark decay of the neutron is affected by the extreme conditions prevailing in the interior of neutron stars remains an open problem.