Buffer gas effect on ground and metastable populations in a pulsed CuBr laser

We have measured the time dependence of the concentration of copper atoms in the ground and metastable states in a pulsed CuBr laser by monitoring the absorption of the atomic copper lines 244.2 and 510.6 nm. In agreement with previous measurements in a CuCl laser, we found the populations to grow after the dissociation pulse, peaking many tens of microseconds later. Temperature and buffer gas species and pressure have a considerable influence on the details of the temporal evolution. The results are interpreted in terms of a schematic mechanism involving parallel dissociation processes. Qualitative agreement with the experimental results is quite good, but no attempt was made to elucidate the physical processes which actually occur during and after the dissociation pulse. In the course of the experiment the radiative transition probability of the 244.2 nm line was measured and found to be 0.26 \times 10^{-7} s -1 .