Conditions favorable for mergers of massive black holes exist in the outer gas disks of massive spiral galaxies, according to a study led by Rochester Institute of Technology astrophysicist Sukanya Chakrabarti. Chakrabarti et al identify an overlooked region that may prove to be rife with orbiting black holes and the origin of gravitational-wave chirps heard by the two Laser Interferometer Gravitational-Wave Observatory (LIGO) detectors in the United...
