  We examine the unusual Fe-Kalpha line profile in MCG-6-30-15 observed by ASCA
during a deep minimum in the source intensity. The intense red wing and
depressed blue wing of the line have been interpreted as evidence for extreme
gravitational redshifts in terms of emission from within six gravitational
radii of a black hole. We find that the data do not uniquely support this
interpretation and can be equally well explained by occultation of the
continuum source and the putative line-emitting accretion disk, which we offer
as an alternative hypothesis. Two problems with previous modeling were that the
equivalent width of the line during the deep minimum was required to be
unusually large (> 1 keV) and the line intensity was thought to increase as the
source became dim. The occultation model does not suffer from these problems.
Our results serve to highlight the hazards of over-interpreting observational
results which have low statistical significance, to the extent that theoretical
implications can become generally accepted when the data do not provide a
strong case for them.

Astrophysics