Relativistic reflection X-ray spectra of accretion disks
  We have calculated the relativistic reflection component of the X-ray spectra
of accretion disks in active galactic nuclei (AGN). Our calculations have shown
that the spectra can be significantly modified by the motion of the accretion
flow and the gravity and rotation of the central black hole. The absorption
edges in the spectra suffer severe energy shifts and smearing, and the degree
of distortion depends on the system parameters, in particular, the inner radius
of the accretion disk and the disk viewing inclination angles. The effects are
significant. Fluorescent X-ray emission lines from the inner accretion disk
could be powerful diagnostic of space-time distortion and dynamical
relativistic effects near the event horizons of accreting black holes. However,
improper treatment of the reflection component in fitting the X-ray continuum
could give rise to spurious line-like features. These features mimic the true
fluorescent emission lines and may mask their relativistic signatures. Fully
relativistic models for reflection continua together with the emission lines
are needed in order to extract black-hole parameters from the AGN X-ray
spectra.
