Shielding a charged black hole

We describe a shielding mechanism for charged black hole immersed in background involving matter fields, solely arising from the Einstein-Maxwell field equations. In particular, we consider generalization of Einstein cluster, that is surrounded by an effective fluid model partially dust cloud. show mechanism, thereof, generic and appears different parametrization problem as well. this process, provide most general electrovacuum solution spacetime region devoid charges, but presence static spherically symmetric charge distribution elsewhere. Side side, also introduce convenient parametrization, providing global Einstein-Maxwell's equations within environment fluid. comment on nature photon sphere, shadow radius eikonal quasi-normal modes cluster.