A novel differential velocity modulation laser spectroscopy

Experimental investigation of a novel differential velocity modulation laser spectroscopy is reported and demonstrated with the spectra of n 2 + A2Dm -X2O g + Meinel system. The S/N ratio excesses 500· ·1, about 60 times higher than that with the traditional non-differential technique. With this technique, we obtained the high-resolution electronic absorption spectra of A2D-X2O+ (1, 0) vibration-al band of CS+ for the first time. It is confirmed that this technique will be a powerful method and receive wide application in studies of new molecular ions.