Year: 2025
Type: article
Abstract: In this paper, we investigate the shadow and optical appearance of the hairy Kerr black hole illuminated by a thin accretion disk. The deformation parameter $$\alpha $$ α and hair parameter $$l_o$$ l o are found to influence the motions of accretion as well as the redshift effect of the photon, such that they significantly affect the shadow and image of the hairy Kerr black hole. In particular, $$l_o$$ l o suppresses the shadow size of the black hole while $$\alpha $$ α enhances it. We then analyze the widths of the direct, lensed ring and photon ring emission regions for the thin accretion disk. It is found that the widths of the direct emission and lensed ring emission change slightly with the parameters, whereas the width of the photon ring emission increases dramatically as $$l_o$$ l o decreases. This feature provides more favorable conditions for observing the photon rings of black hole. Finally, we study the redshift of the direct and lensed images, showing that the maximal blueshift point is shifted by the change of the parameters. We argue that our study provides a preliminary theoretical prediction that the image of the hairy Kerr black hole, especially the photon ring structure, may be used to constrain the hair parameters with future high-precision astronomical observation.
Source: The European Physical Journal C
Authors: Yuan Meng, Xi-Jing Wang, Yong-Zhuang Li, Xiao-Mei Kuang
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: diamond
Awards: G4182537444, G7957248817, G830582713
OpenAlex ID: W4411112107