The shell of incoherent charged matter falling onto a charged rotating black hole

The motion of the shell of charged test particles falling radially from res t at infinity with zero total angular momentum onto a Kerr-Newman black hol e is studied. The shell, initially spherical, becomes prolate along the axi s of symmetry of the hole during the fall. The shape of the shell from the viewpoint of distant observers is characterized by means of the photons mov ing along geodesics of the outgoing principal null congruence. The motion o f the shell is examined analytically for large distances and near the horiz on. In the special case, when at large distances of the hole the attractive Newton gravitational force is compensated by the repulsive Coulomb force, the complete motion is given explicitly in terms of elementary functions.