Black hole superradiance signatures of ultralight vectors
Abstract
The process of superradiance can extract angular momentum and energy from astrophysical black holes (BHs) to populate gravitationally bound states with an exponentially large number of light bosons. We analytically calculate superradiant growth rates for vectors around rotating BHs in the regime where the vector Compton wavelength is much larger than the BH size. Spin1 bound states have superradiance times as short as a second around stellar BHs, growing up to a thousand times faster than their spin0 counterparts. The fast rates allow us to use measurements of rapidly spinning BHs in xray binaries to exclude a wide range of masses for weakly coupled spin1 particles, 5 ×10^{14}2 ×10^{11} eV ; lighter masses in the range 6 ×10^{20}2 ×10^{17} eV start to be constrained by supermassive BH spin measurements at a lower level of confidence. We also explore routes to detection of new vector particles possible with the advent of gravitational wave (GW) astronomy. The LIGOVirgo Collaboration could discover hints of a new light vector particle in statistical analyses of masses and spins of merging BHs. Vector annihilations source continuous monochromatic gravitational radiation which could be observed by current GW observatories. At design sensitivity, Advanced LIGO may measure up to thousands of annihilation signals from within the Milky Way, while hundreds of BHs born in binary mergers across the observable Universe may superradiate vector bound states and become new beacons of monochromatic gravitational waves.
 Publication:

Physical Review D
 Pub Date:
 August 2017
 DOI:
 10.1103/PhysRevD.96.035019
 arXiv:
 arXiv:1704.05081
 Bibcode:
 2017PhRvD..96c5019B
 Keywords:

 High Energy Physics  Phenomenology;
 Astrophysics  Cosmology and Nongalactic Astrophysics;
 Astrophysics  High Energy Astrophysical Phenomena;
 General Relativity and Quantum Cosmology
 EPrint:
 16 pages + appendices, 12 figures