Scalar radiation emitted from a rotating source around a   Reissner-Nordstrom black hole
  We investigate the radiation emitted from a scalar source in circular orbit around a Reissner-Nordstrom black hole. Particle and energy emission rates are analytically calculated in the low- and high-frequency regimes and shown to be in full agreement with a numerical calculation. Our investigation is connected with the recent discussion on the validity of the cosmic censorship conjecture in the quantum realm. 
Luis C. B. Crispino, Andre R. R. da Silva and George E. A. Matsas