Radiation properties of a regular black hole embedded in a Dehnen-type dark matter halo with a thin accretion disk

TL;DR

This paper studies the observational features of a regular black hole within a Dehnen dark matter halo, analyzing shadow, accretion disk radiation, and optical appearance, constrained by real astronomical data.

Contribution

It introduces a model of a regular black hole embedded in a Dehnen halo and systematically examines its observational signatures, constrained by M87* and Sgr A* data.

Findings

Larger model parameter a enlarges the accretion disk's effective radiation area.

Increasing a enhances asymmetry and Doppler boosting in black hole images.

The model's parameters are constrained by observational data at 1σ and 2σ confidence levels.

Abstract

We investigate the shadow, timelike geodesic structure, radiation properties of thin accretion disks, and optical appearance of a static spherically symmetric regular black hole, constructed based on the Dehnen-type density profile. Using observational data from M87* and Sgr A*, we constrain the model parameter $a$ at both $1\sigma$ and $2\sigma$ confidence levels. Based on the Page--Thorne model, we calculate the local radiative flux, redshift factor distribution, and the radiation flux received by a distant observer, systematically examining the effects of the parameter $a$ and the viewing angle on the black hole image. The results show that larger $a$ will enlarge the effective radiation area of the accretion disk and significantly enhance the asymmetry and Doppler boosting effects of the direct and secondary images at large viewing angles.