Pulsed Laser Photoacoustic Detection of SO(2) Near 225.7 nm.

A trace concentration of SO(2) near 225.7 nm has been detected with a master-oscillator power-oscillator laser system for the first time, to our knowledge. A photoacoustic absorption spectrum of SO(2) has been recorded on the (1)A(2)-(1)B(2) (pi-pi*) transition. Parametric dependence of the photoacoustic signal has been investigated. A detection limit (signal-to-noise ratio of 1) of 1.3 parts in 10(9) [1.3 ppbv (parts per billion by volume)] for SO(2) have been determined at 1 atmospheric pressure inside a photoacoustic cell.