Superradiance and quasi-bound states in the parameter space of the Kerr-Newman black hole

Abstract

We explored the parameter space of black hole superradiant instability due to massive scalar fields in a Kerr-Newman (KN) black hole. Superradiant instabilities occur when both the superradiance condition and quasi-bound state condition are simultaneously satisfied. Using the VBK method, we solved for resonant modes and determined which solutions will instigate black hole superradiant instabilities. The results were plotted over the parameter space of charge and spin of the Kerr-Newman black hole including the Kerr and Reissner-Nordström limits.