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.