J. Phys. IV France 01 (1991) C7-471-C7-476
INTRACAVITY LASER ABSORPTION SPECTROSCOPY OF NO2 AND CH4 COOLED IN A SLIT JET SUPERSONIC EXPANSIONA. CAMPARGUE1, M. CHENEVIER1, A. DELON2, R. JOST2 and F. STOECKEL1
1 Laboratoire de Spectrométrie Physique, Université Joseph Fourier/Grenoble I, BP. 87, F-38402 St-Martin-d'Hères cedex, France
2 Service National des Champs Intenses, C.N.R.S., BP. 166X, F-38042 Grenoble cedex, France
The intracavity Laser Absorption Spectroscopy (ICLAS) has been use to observe weak absorption of NO2 and CH4 cooled in a supersonic jet through a slit. By this method, the thermally congested spectrum of the molecules is drastically simplified and analysis becomes possible. On NO2 we report preliminary results in the 13 470 - 14 440 cm-1 energy range where 20 vibronic bands have been observed. On CH4 the VCH = 5 overtone centered at 13 750 cm-1, which is unresolved at room temperature, displays only few lines not yet analysed.
© EDP Sciences 1991