Mechanisms for improved XeF laser performance at elevated temperatures.

Lasing spectra and output efficiency have been measured for four Ne/Xe/NF(3) laser mixtures from 300 to 450 K. These high resolution spectra have been correlated with a theoretical rotational bandhead structure to identify rotational states contributing to two narrowband emissions in the 351-nm band. Rotationalvibrational population shifts appear to be the most important mechanisms responsible for the increase in laser efficiency with temperature. Increased ground-state dissociation and decreased narrowband absorption may not be as important as previously thought.