Publication date: Aug 2009
Abstract:
In the framework of the braneworld models, rotating black holes can be
described by the Kerr metric with a tidal charge representing the
influence of the non-local gravitational (tidal) effects of the bulk
space Weyl tensor onto the black hole spacetime. We study the influence
of the tidal charge onto profiled spectral lines generated by radiating
tori orbiting in vicinity of a rotating black hole. We show that with
lowering the negative tidal charge of the black hole, the profiled line
becomes to be flatter and wider keeping their standard character with
flux stronger at the blue edge of the profiled line. The extension of
the line grows with radius falling and inclination angle growing. With
growing inclination angle a small hump appears in the profiled lines due
to the strong lensing effect of photons coming from regions behind the
black hole. For positive tidal charge ( b > 0) and high inclination
angles two small humps appear in the profiled lines close to the red and
blue edge of the lines due to the strong lensing effect. We can conclude
that for all values of b, the strongest effect on the profiled lines
shape (extension) is caused by the changes of the inclination angle.
Authors:
Schee, Jan; Stuchlík, Zdeněk;