Imaging characteristics of Frolov black holes under different accretion models

Abstract We simulate the light trajectories of the Frolov black hole and investigate the image characteristics of the black hole by performing numerical calculations and using light ray tracing methods. It is observed that rising values of parameters l and q lead to a smaller event horizon radius for the Frolov black hole and weaken its ability to deflect light rays. We discuss the image characteristics under the background of the spherical accretion model and the thin disk accretion model. It is found that the static spherical accretion model yields a higher observational intensity compared to the infalling spherical accretion model. In the geometrically thin and optically thin accretion disk, direct emission is the main source of light intensity, while the contribution from photon ring emission is weaker. In the model of a slim disk with optically thick accretion flow, images observed at various inclination angles exhibit notable differences. These results indicate that when both parameters l and q are large, the appearance of the Frolov black hole differs significantly from that of the Schwarzschild black hole. Therefore, in future observational studies, the image will become an important tool for distinguishing between these two types of black holes.