A search for gravitational lensing effects in Fermi GRB data

Abstract

As GRBs trace the high-z Universe, there is a non-negligible probability of a lensing effect being imprinted on the lightcurves of the bursts. We propose to search for lensed candidates with a cross-correlation method, by looking at bursts days to years apart coming from the same part of the sky. We look for similarities and hypothesize a Singular Isothermal Sphere (SIS) model for the lens. A lensed pair would enable us to constrain the mass of the lensing object. Our search did not reveal any gravitationally lensed events.