Abstract

Very cold molecular beam of Cs2 is generated by a high temperature supersonic jet source. State-specific photofragment yield spectrum is obtained in the orange band of Cs2. Asymmetric line shapes are observed. The Fano line shape parameter, q, shows a gradual sign change, which is called “q-reversal”. A very broad absorption band which has about 50 cm-1 width is observed and explained to occur through the perturbation by the D1u+ state. The complex resonance line shapes are attributed to the interfering resonances.