Cascade theory for double K x-ray emission in transfer and excitation collisions

We propose a cascade model to interpret a recent, novel experiment of S/sup 15+/+H/sub 2/ collisions with simultaneous excitation capture in which two K x rays were detected. Cascade effects leading to double K x-ray emission are carefully examined to obtain K..cap alpha..-K..cap alpha.., K..cap alpha..-K..beta.., and K..cap alpha..-K..gamma.. (and higher states) coincidence cross sections. The overall spectral shapes and absolute magnitudes are consistent with the predictions of the model.