Effects from dark matter halos on x-ray pulsar pulse profiles

作者：Yukun Liu, Hong-Bo Li, Yong Gao, Lijing Shao, Zexin Hu · 发表于：Physical review. D/Physical review. D. · 年份：2024 · DOI：10.1103/physrevd.110.083018 · 被引用次数：9 · 研究领域：Dark Matter and Cosmic Phenomena、Pulsars and Gravitational Waves Research、Cosmology and Gravitation Theories

Neutron stars (NSs) can capture dark matter (DM) particles because of their deep gravitational potential and high density. The accumulated DM can affect the properties of NSs. In this work we use a general relativistic two-fluid formalism to solve the structure of DM-admixed NSs (DANSs) and the surrounding spacetime. Specifically, we pay attention to the situation where those DANSs possess DM halos. Due to the gravitational effect of the DM halo, the pulse profile of an x-ray pulsar is changed. Our study finds a universal relation between the peak flux deviation of the pulse profile and ${M}_{\mathrm{halo}}/{R}_{\mathrm{BM}}$, which is the ratio of the DM halo mass, ${M}_{\mathrm{halo}}$, to the baryonic matter (BM) core radius, ${R}_{\mathrm{BM}}$. Our results show that, when ${M}_{\mathrm{halo}}/{R}_{\mathrm{BM}}=0.292$ and the DM particle mass ${m}_{f}=0.3\text{ }\text{ }\mathrm{GeV}$, the maximum deviation of the profile can be larger than 100%, which has implications in x-ray pulsar observation.