Periodic orbits and observational accretion disk around a Schwarzschild-like black hole surrounded by dark matter halo

TL;DR

This paper studies how a dark matter halo influences the orbital dynamics and observable properties of accretion disks around a Schwarzschild-like black hole, providing insights into spacetime geometry and astrophysical signals.

Contribution

It introduces a detailed analysis of periodic orbits and accretion disk characteristics in a black hole surrounded by a King-type dark matter halo, highlighting the modifications caused by dark matter.

Findings

Dark matter halo alters stable orbit radii and properties.

Accretion disk images and spectra are affected by dark matter presence.

Observable signatures depend on inclination angles and dark matter distribution.

Abstract

In this work, we investigate the dynamics of periodic orbits and the properties of accretion disks around a Schwarzschild-like black hole (BH) immersed in a King-type dark matter (DM) halo. Our analysis focuses on how the presence of the King DM halo influences both the behavior of periodic orbits and the radiative characteristics of the accretion disk. We begin by examining time-like periodic geodesic orbits for various configurations characterized by different energy and angular momentum values, represented by the integers $(z, w, v)$. Furthermore, we explore the effects of the King DM halo on time-like periodic geodesics, marginally bound orbits, and innermost stable circular orbits, thereby providing a deeper understanding of how the DM halo environment modifies the behavior of these stable orbits and timelike particle geodesics. Finally, we analyze the null geodesics and the accretion disk properties by studying their direct and secondary images, redshift distributions, and radiation fluxes as observed at infinity for a range of inclination angles. This approach allows us to gain valuable insights into the spacetime geometry of a Schwarzschild-like BH within the King-type DM halo, its physical and radiative properties in the accretion disk, and the corresponding observational implications.