A two-dimensional theory is developed for the vorticity just downstream of
a curved, unsteady shock wave. By utilizing Crocco's equation, an explicit,
formula is obtained for the vorticity that does not require a perfect gas
and that holds for arbitrary conditions upstream of the shock wave. The ana
lysis is applied to the flow just downstream of the reflected shock tl-lat
occurs in a single-Mach reflection pattern. Flow conditions are based on an
interferometric photograph of Ben-Dor and Glass (1978). In this case, the
reflected shock is weak everywhere from its upstream intersection with the
wall to the triple point. The vorticity has a singularity and a change of s
ign near the triple point that indicates the presence of a weak shear layer
downstream of this location.