Pair creation in the vortex-driven magnetic fields of black holes

Abstract

We study the effects of pair creation on the radiation emerging from black holes under the assumption that the magnetic fields are vortex driven. In particular, for a sufficiently broad range of supermassive black holes, we investigated the energies at which photons undergo decay under the influence of a strong magnetic field, producing electron-positron pairs. Depending on particular physical parameters, it has been shown that in certain scenarios high or very high energy emission generated by black holes will be strongly suppressed, thus, will be unable to escape a zone where radiation is generated. In particular, photons with energies exceeding $\sim 1$ GeV will never leave the magnetosphere if they are generated at the scale 10$R_g$ and the threshold is of the order of $1$ TeV, if the emission is produced at $\sim 100\; R_g$. Analysing the process versus the black hole mass, assuming the region $100\; R_g$, it has been shown that for the considered lowest mass, the photons with energies $250$ GeV will never leave the black hole and for the considered highest mass the corresponding value is $\sim 250$ TeV.