Mergers of Charged Black Holes: Gravitational-wave Events, Short Gamma-Ray Bursts, and Fast Radio Bursts
The discoveries of GW150914, GW151226, and LVT151012 suggest that double black hole (BH-BH) mergers are common in the universe. If at least one of the two merging black holes (BHs) carries a 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 q ∼ (10-9-10-8) of the critical charge Qc of the BH. At large radii, dissipation of the Poynting flux energy in the outflow would power a shortduration high-energy transient, which would appear as a detectable short-duration gamma-ray burst (GRB) if the charge can be as large as q ∼ (10-5 10-4). The putative short GRB coincident with GW150914 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 BHs. © 2016. The American Astronomical Society. All rights reserved.
radiation mechanisms: non-thermal; stars: black holes
Mergers of Charged Black Holes: Gravitational-wave Events, Short Gamma-Ray Bursts, and Fast Radio Bursts.
Astrophysical Journal Letters, 827(2),