STUDY OF FLUORESCENT LIFETIME OF THE ν3 VIBRATIONAL MODE IN SF6

Abstract

Spontaneous emission from the ν₃ fundamental vibration in SF₆ gas after excitation by a pulse from a Q‐switched CO₂ laser is observed. The pressure dependence of the flourescence decay time indicates that, at low pressure, diffusion of excited molecules followed by deactivation at vessel walls is the dominant relaxation mechanism. At higher pressures, the time for collisional deactivation within the bulk of the gas is measured. Evidence which suggests that a longitudinal‐acoustic‐shock wave was present in the gas at higher pressures is given.