Dark matter effects on tidal deformabilities and moment of inertia in a hadronic model with short-range correlations

TL;DR

This paper investigates how dark matter influences the tidal deformability and moment of inertia in neutron stars using a relativistic hadronic model with short-range correlations, aligning theoretical predictions with gravitational wave observations.

Contribution

It introduces a relativistic mean-field model including dark matter and short-range correlations, demonstrating its consistency with gravitational wave constraints on neutron star properties.

Findings

Dark matter decreases tidal deformability as Fermi momentum increases.

Model aligns with GW170817 observational limits on tidal deformability.

Inclusion of dark matter preserves the I-Love relation in neutron stars.

Abstract

In this work we study the outcomes related to dimensionless tidal deformability $(\Lambda)$ obtained through a relativistic mean-field (RMF) hadronic model including short-range correlations (SRC) and dark matter (DM) content [Phys. Rev. D 105, 023008 (2022)]. As a dark particle candidate, we use the lightest neutralino interacting with nucleons through the Higgs boson exchange. In particular, we test the model against the constraints regarding the observation of gravitational waves from the binary neutron star merger GW170817 event provided by LIGO and Virgo collaboration (LVC). We show that $\Lambda$ decreases as the dark particle Fermi momentum ($k_F^{DM}$) increases. This feature favors the RMF-SRC-DM model used here to satisfy the limits of $\Lambda_{1.4}=190^{+390}_{-120}$ ($\Lambda$ of a $1.4M_\odot$ neutron star), and $\tilde{\Lambda}=300^{+420}_{-230}$ given by the LVC. We also show that as $k_F^{DM}$ increases, $\Lambda_1$ and $\Lambda_2$, namely, tidal deformabilities of the binary system, are also moved to the direction of the GW170817 observational data. Finally, we verify that the inclusion of DM in the system does not destroy the \mbox{$I$-Love} relation (correlation between $\Lambda$ and dimensionless moment of inertia, $\bar{I}$). The observation data for $\bar{I}_\star\equiv\bar{I}(M_\star)=11.10^{+3.68}_{-2.28}$, with $M_\star=1.338M_\odot$, is attained by the RMF-SRC-DM model.