Probing the Impact of WIMP Dark Matter on Universal Relations, GW170817 Posterior and Radial Oscillations

TL;DR

This paper explores how WIMP dark matter influences neutron star properties, universal relations, and radial oscillations, revealing that dark matter softens the EOS, shifts mass-radius relations, and increases oscillation frequencies, with implications for dark matter-admixed neutron stars.

Contribution

It introduces a detailed analysis of dark matter effects on neutron star universal relations, mass-radius curves, and oscillation modes within the NMSSM framework, highlighting potential observational signatures.

Findings

Dark matter softens the neutron star EOS.

Mass-radius relations shift with dark matter presence.

Radial oscillation frequencies increase with dark matter mass.

Abstract

In this study, we investigate the impact of Weakly Interacting Massive Particles (WIMPs) dark matter (DM) on $C-\Lambda$ universal relations, GW170817 posterior and radial oscillations of neutron stars (NSs) by considering the interactions of uniformly trapped neutralinos as a DM candidate with the hadronic matter through the exchange of the Higgs boson within the framework of the Next-to-Minimal Supersymmetric Standard Model (NMSSM). The hadronic equation of state (EOS) is modeled using the relativistic mean-field (RMF) formalism with IOPB-I, G3, and QMC-RMF series parameter sets. Presence of DM softens the EOS at both the background and the perturbation levels that implies a small shift to the left in the posterior accompanied by a much larger jump in the left of the mass-radius curves with increasing DM mass. It is observed that EOSs with DM also satisfy the $C-\Lambda$ universality relations among their-selves but get slightly shifted to the right in comparison to that without considering DM. Additionally, we find that the inclusion of DM allows the mass-radius ($M-R$) curves to remain consistent with observational constraints for HESS J1731-347, indicating the possibility of classifying it as a dark matter-admixed neutron star (DMANS). Moreover, we explore the impact of DM on the radial oscillations of pulsating stars and investigate the stability of NSs. The results demonstrate a positive correlation between the mass of DM and the frequencies of radial oscillation modes.