Knowledge Bank

A tunable, injection-locked ArF excimer laser been used to obtain single photon laser induced fluorescence spectra from a highly vibrationally excited (up to $\nu \prime \prime \approx 40$), nonequilibrium CO/Ar plasma. The combination of broadband emission and rotationally resolved narrowband scanning excitation spectra has been used to determine that the fluorescence signal is due to the resonant excitation between the $\nu \prime \prime =20$ level of the $X1\Sigma +$ state and the $\nu \prime =2$ level of the . This spectroscopic data suggests that with appropriate care to avoid extraneous multi-photon chemical $processesc$, the $D^{\prime}\rightarrow $X fluorescence may be used as a rotational temperature diagnostic as long as the $CO\nu \prime \prime =20$ vibrational state is sufficiently populated.