Observation of the v = 3←0 band of SO(X 3Σ−) with a difference frequency laser

Abstract
The second overton band (v = 3→0) of SO(X 3Σ) near 3 μm has been observed by using a tunable difference frequency laser spectrometer and a 2 m multiple‐reflection discharge cell. An analysis of the overtone data yields the band origin and molecular constants of the v = 3 state. (AIP)