CRISIS IN CHAOTIC SCATTERING

We show that in a chaotic scattering system the stable and unstable fo liations of isolated chaotic invariant sets can become heteroclinicall y tangent to each other at an uncountably infinite number of parameter values. The first tangency, which is a crisis in chaotic scattering, provides the link between the chaotic sets. A striking consequence is that the fractal dimension of the set of singularities in the scatteri ng function increases in the parameter range determined by the first a nd the last tangencies. This leads to a proliferation of singularities in the scattering function and, consequently, to an enhancement of ch aotic scattering.