Abstract

Raman excitation and laser-induced electronic fluorescence is a double resonance time-of-flight technique for determining instantaneous velocity profiles in high speed airflows. Stimulated Raman pumping is used to vibrationally tag molecular oxygen by excitation to the v = 1 vibrational level. After suitable time delay, the flow is interrogated via Schumann-Runge fluorescence using an ArF laser at 0.193 μm.¹ Q-branch stimulated Raman scattering from high pressure oxygen is an attractive approach to generating the Stokes beam for Raman pumping² but is complicated due to the low gain and by competing processes such as stimulated Brillouin scattering.

© 1990 Optical Society of America