THE STUDY OF DEPOLARIZING COLLISIONS WITH THE USE OF COHERENT TRANSIENT PROCESSES

The method of stimulated photon echo with specially chosen polarizatio ns of radiation in the pumping pulses is applied to the investigation of the collisional relaxation of orientation and alignment in an SF6 m olecular gas and in mixtures of SF6 with He and Xe buffer gases. For p ure SF6 gas, the rate of the collisional decay of alignment, gamma((2) )/p = (38 +/- 5) x 10(6) s(-1) Torr(-1), is somewhat higher than the r ate of the collisional decay of orientation, gamma((1))/p = (32 +/- 5) x 10(6) s(-1) Torr(-1). For a mixture of SF6 with a heavy Xe buffer g as, these relaxation rates are virtually equal to each other. Within t he accuracy of experimental errors, we did not detect any dependence o f gamma((2)) and gamma((1)) on the velocity of translational motion fo r the SF6 + Xe mixture, which is consistent with the commonly accepted model of depolarizing collisions.