Time evolution of spinor perturbations in regular black holes

In this report we present results concerning the study of complete time evolution of massless fermion perturbations propagating in several four dimensional regular black hole space-times. The black hole solution arises from coupling gravity with external matter sources, like nonlinear electrodynamics or some phantom fields. After numerical integration we obtain the time evolution profiles for fermion fields in this space-times. By fitting the numerical data, we compute the quasinormal frequencies that characterize the test field evolution at intermediary times, and for late times, we find power law tails, in strong similarity with usual results for non regular black holes. Quasinormal modes was also investigated using a WKB approach at six order beyond the eikonal limit, obtaining a good correspondence with the numerical calculated frequencies.