Mergers of Charged Black Holes: Gravitational Wave Events, Short Gamma Ray Bursts, and Fast Radio Bursts
The discoveries of GW 150914, GW 151226, and LVT 151012 suggest that double black hole (BH BH) mergers are common in the universe. If at least one of the two merging black holes carries certain amount of charge, possibly retained by a rotating magnetosphere, the inspiral of a BH BH system would drive a global magnetic dipole normal to the orbital plane. The rapidly evolving magnetic moment during the merging process would drive a Poynting flux with an increasing wind power. The magnetospheric activities during the final phase of the merger would make a fast radio burst (FRB) if the BH charge can be as large as a factor of \hat q \sim (10^ 9} 10^ 8} of the critical charge $Q_c$ of the BH. At large radii, dissipation of the Poynting flux energy in the outflow would power a short duration high energy transient, which would appear as a detectable short duration gamma ray burst (GRB) if the charge can be as large as \hat q \sim (10^ 5} 10^ 4} The putative short GRB coincident with GW 150914 recorded by Fermi GBM may be interpreted with this model. Future joint GW/GRB/FRB searches would lead to a measurement or place a constraint on the charges carried by isolate black holes.