Observational properties of coherent quantum black holes

We consider null and timelike geodesics around a spherically symmetric, nonrotating coherent quantum black hole (CQBH). The classical limit of the geometry of a CQBH departs from that of the Schwarzschild spacetime at short scales and depends on one parameter Rs which can be interpreted as the physical radius of the "quantum"core. We study circular orbits, photon rings, and lensing effects and compare them with the Schwarzschild metric. Using the relativistic ray-tracing code gyoto, we produce a simulation of the shadow and show that thin accretion disks around a CQBH possess unique ring structures that distinguish them from other theoretical models.