Direct Simulation Monte Carlo Dissociation Model Evaluation: Comparison to Measured Cross Sections

Recent measurements of collision-induced dissociation (CID) cross sections for Ar sub 2 exp + -Ar collisions for vibrationally cold and hot cases are utilized to test and compare several CID models that have been proposed for the direct simulation Monte Carlo (DSMC) technique. The idea that the CID process is strongly favored by vibrational energy is discussed relative to the various models. The Ar sub 2 exp + data do not show any vibrational favoring of the CID cross sections. The predictions of the DSMC models are examined using values of their adjustable parameters suggested in the literature. It is shown that some DSMC CID models have much more physically realistic behavior in terms of their cross sections than others.