STARK-BROADENING USING CROSSED GAUSSIAN BEAMS IN STIMULATED RAMAN-SPECTROSCOPY OF N-2

We have studied the effect of crossing two Gaussian laser beams on Sta rk-broadened line shapes in stimulated Raman gain spectroscopy of N-2 Q-branch transitions. At about 350 GW/cm(2) of pump laser peak intensi ty in a 0.11 atm, 298 K gas sample, the Stark-broadened crossed-beam l inewidth is about twice the linewidth of collinear beams. For the cros sed condition, the two focussed (f/93) beams are crossed at 0.9 deg. T he line shape measurements are in qualitative agreement with a numeric al model for Stark-broadened line shapes that spatially resolves the l aser intensity variations over the sample volume. Published by Elsevie r Science Ltd.