  We propose an eclipsing light-curve diagnosis for black-hole accretion flows.
When emission from an inner accretion disk around a black hole is occulted by a
companion star, the observed light curve becomes asymmetric at ingress and
egress on a time scale of 0.1-1 seconds. This light-curve analysis provides a
means of verifying the relativistic properties of the accretion flow, based on
the special/general relativistic effects of black holes. The ``skewness'' for
the eclipsing light curve of a thin disk is $\sim 0.08$, whereas that of a slim
disk is $\sim 0$, since the innermost part is self-occulted by the disk's outer
rim.

Astrophysics