Investigation of condensation of $SF_6$ in a free jet in the presence of laser radiation

An experimental investigation was made of the interaction between cw $CO_2$ laser radiation in the $10,6\mu m$ range and $SF_6$ in a free jet with and without condensation. Calculations of the two-dimensional expansion of $SF_6$ showed that vibrational-translational exchange had a substantial influence on the jet parameters. It was observed that absorption of laser radation by the gas under conditions of supersonic expansion resulted in nonequilibrium heating of the gas, increased its mass velocity, and reduced its density in the molecular beam. In expansion regimes with condensation it was found that $CO_2$ laser radiation did not interact with dimers formed in the initial condensation stage and prevented the formation of or destroyed clusters formed in the advanced condensation stage.