Comparison of measured total integral cross sections for noble gas dimer-atom systems with IOSA calculations

Experimentally determined total integral cross sections for noble gas dimer-atom systems, involving the energetically accessible channels of excitation, exchange and dissociation are compared with theoretical values calculated using a simple formula. This simple formula is derived using the multichannel optical theorem and the infinite order sudden approximation (IOSA). The potential is well approximated by the sum of known pair potentials. Setting the IOSA parameters L and K equal to the angular momentum and the wave number of the initial channel, respectively, the largest error between the experimental and theoretical results is about 10%. We noticed that a proper choice of the relation between K and the collision energy greatly reduces this error; a possible explanation cannot be given.