http://arxiv.org/abs/1501.07605
We show that the magnetic dipole and gravitational radiation emitted by a pulsar can undergo superradiant scattering off a spinning black hole companion. We find that the relative amount of superradiant modes in the radiation depends on the pulsar’s angular position relative to the black hole’s equatorial plane. In particular, when the pulsar and black hole spins are aligned, superradiant modes are dominant at large angles, leading to an amplification of the pulsar’s luminosity, whereas for small angles the radiation is dominantly composed of non-superradiant modes and the signal is attenuated. This results in a characteristic double orbital modulation of the pulsar’s luminosity that can be used to search for observational signatures of superradiant scattering in astrophysical black holes, providing an important test of general relativity.
J. Rosa
Mon, 2 Feb 15
9/49
Comments: 5 pages, 3 figures