Single-shot time-domain coherent anti-Stokes Raman scattering: application to temperature and velocity measurements...

It is shown that a new approach in time-domain coherent anti-Stokes Raman spectroscopy can be used to perform single-shot measurements of the static temperature and velocity in low-pressure supersonic flows. Instead of repetitively probing the macroscopic polarizibility coherently driven by a short-duration pump and Stokes pulses with variable delay times, we create the coherence with a long-duration pump and a short-duration Stokes pulse and probe it continuously with the same pump pulse.The decay of the anti-Stokes signal reveals the static temperature. The beating between two signals that are created in opposite crossing directions with respect to the flow direction gives the velocity of the flow.