The collapse of black hole binaries without a following or a simultaneous emission of high energy electromagnetic radiation has led us to predict that this kind of emission should occur immediately before the collapse. The theoretical model on which this prediction was made involves plasma structures which are assumed to exist around black hole binaries. These can sustain intrinsic plasma collective modes that have characteristic “low” frequencies about equal to the orbiting frequencies of the binary system components. As the collapse approaches, with the loss of angular momentum by emission of gravitational waves from the binary system, it was suggested that intrinsic plasma density oscillations having the frequency of the fluctuating component of the gravitational potential are excited in the surrounding plasma structure. Thus the precursor to the event tentatively identified by the Agile X-ray observatory can be associated with the high energy radiation emission due to the fields produced by excitation of the proposed plasma modes. Following that, the August 17, 2017 event, identified first by the LIGO-Virgo detection of gravitational waves and featuring the inferred collapse of a neutron star binary, gave ample evidence of a precursor of electromagnetic emission preceding the collapse.
See for example
PlPhR 43 289-297
PRL 118 221101
ApJL 847 L20
Sponsor(s): Lab for Nuclear Science, Physics
Contact: Bruno Coppi, 26-547, 617-253-2507, firstname.lastname@example.org