Key points are not available for this paper at this time.
A technique which employs heretofore unappreciated aspects of the optical stimulated echo was developed and used to measure the total scattering cross section for Na (3S₁₂) -He and Na (3P₁₂) -He collisions. The repulsive-core-dominated Na (3S₁₂) -He collision is found to be relatively soft. The cross section for degradation of the 3S₁₂-3P₁₂ superposition, determined from photon-echo-decay measurements, is anomalous in that it is smaller than the total elastic-scattering cross section with Na in either state separately.
Mossberg et al. (Mon,) studied this question.