INFLUENCE OF COLLISIONAL COUPLING ON THE ENERGY EXTRACTION FROM THE B-STATE, C-STATE, AND D-STATE IN KRF

Collisional coupling between the B, C, and D states of KrF is measured in a discharge pumped KrF laser. Detection of the time resolved populations in the three states via measurement of the side fluorescence in the B→X, C→A, and D→X bands is used to record the collisional relaxation from the C and D state to the B state during laser emission. The experimentally determined limits for the collisional coupling times are τB-C≦1 ns and τB-D,τC-D<20 ns at total pressures of 2 bar. Investigation of the B→X fluorescence band shows that the vibrational manifold of the B state is not thermalized during laser emission. The V-V,T coupling time is estimated to be τV-V,T=4±2 ns. The influence of collisional coupling on energy extraction in the KrF laser is discussed. © 1979 Springer-Verlag.