Fermion stars as gravitational lenses

Abstract

We study in detail gravitational lensing caused by a supermassive fermion star and compare it with lensing by a black hole of the same mass. It is argued that lensing effects, being very distinct, may shed some light on the yet unexplained nature of the compact dark massive object at the Galactic center.

Comments: revised, 17 pages, 13 figures included, to appear in Astrophys. J