Dynamical motion of matter around a charged black hole

We investigate the dynamical motion of test particles and accretion processes around spherically symmetric charged black hole. We first show the derivation of the Paczyňski-Wiita (PW) potential for any spherically symmetric spacetime and present analytical form of the PW potential in the Reissner-Nordström (RN) spacetime and the RN-type spacetime. We study the dependence of the characteristic orbits of test (neutral and charged) particles around a charged black hole from two main parameters, namely, charge of RN black hole and the interaction of charged particle with the external electromagnetic field of the black hole and present graphical trajectories of test particles around the black hole. It is shown that with increasing the absolute value of interaction parameter, |qQ|, the innermost stable circular orbit (ISCO) radius for charged particle always increases. It is also shown that the energy efficiency for a charged particles can reach up to 60% in the presence of an external charged black hole, while for neutral particles it can reach up to 8% for neutral particles. The capture cross-section of the photon is by the charged black and the optical appearance of the thin accretion disk around the charged black. Finally, we have studied the flux energy and the thermal spectrum of the accretion disk consisting of the polytropic gas, around the charged black hole.