LASER EXCITATION SPECTRUM OF THE SCHUMANN-RUNGE (0,12) BAND OF OXYGEN

Abstract

Although the Schumann-Runge system, $B^{3}{\Sigma^{-}}_{u}- X^{3}{\Sigma^{-}}_{g}$, is the most studied electronic transition of $O_{2}$, its spectroscopy and predissociation mechanisms are still not very well known, We used a pulsed, tunable dye laser to obtain a high resolution scan of the B-X (0,12) band of vibrationally excited $O_{2}$ formed by photodissociation of ozone ar 266 nm, the fourth harmonic of a Nd:YAG laser. The triplet splitting due to spin interactions for a number of rotational levels is observed for the first time and rotational levels up to N"" = 47 have been recorded. The broadened rotational lines indicate that the predissociation rate for the $\nu' = 0$ level is much higher than previous estimates.