Exploring non-radial oscillation modes in dark matter admixed neutron stars

TL;DR

This study investigates how dark matter influences the oscillation modes of neutron stars, revealing significant effects on p-mode frequencies and providing constraints on dark matter parameters within these stars.

Contribution

It introduces a model of dark matter admixed neutron stars considering gravitational interactions and analyzes their non-radial oscillation modes under the Cowling approximation.

Findings

Dark matter significantly lowers p-mode frequencies in neutron stars.

Effects on f-mode frequencies are less pronounced.

Most probable dark matter parameters are identified within the studied range.

Abstract

Because of their extreme densities and consequently, gravitational potential, compact objects such as neutron stars can prove to be excellent captors of dark matter particles. Considering purely gravitational interactions between dark and hadronic matter, we construct dark matter admixed stars composed of two-fluid matter subject to current astrophysical constraints of maximum mass and tidal deformability. We choose a wide range of parameters to construct the dark matter equation of state, and the DDME2 parameterization for the hadronic equation of state. We then examine the effect of dark matter on the stellar structure, tidal deformability and non-radial modes considering the relativistic Cowling approximation. We find the effect on p-modes is substantial, with frequencies decreasing up to the typical $f-$mode frequency range for most stars with a dark matter halo. The effects on the f-mode frequency are less extreme. Finally, we find the most probable and $1\sigma$ values of the dark matter parameters used in this study.