Gravitational Lensing by Rotating Naked Singularities in the Equatorial Plane

摘要

We model massive compact objects in galactic nuclei as stationary, axially-symmetric naked singularities in the massless Einstein scalar field theory and study the resulting gravitational lensing in the strong deflection limit. In this approximation we compute the position of the relativistic images and the flux ratio of the outermost and the innermost images for the weakly naked singularities (those contained within at least one photon sphere) and the results are compared with the case of strongly naked singularities (those not contained within any photon sphere). All of the lensing quantities are compared to particular cases as Schwarzschild and Kerr black holes as well as Janis–Newman–Winicour naked singularities.