15min:

MASAKAZU NAKAJIMA AND YASUKI ENDO, Department of Basic Science, The University of Tokyo, Tokyo 153-8902, Japan.

The d³ _g-c^{3 +}_u band system of C₂ was observed in a discharge flow cell by laser induced fluorescence spectroscopy. Although the observation of the band system has been reported for the jet-cooled C₂ molecule, transitions involving higher rotational levels were observed in the present study. Improved molecular constants for several vibrational levels of the c^{3 +}_u state will be presented. Furthermore, the bands with v''=5,6,7 were newly observed in a discharged supersonic jet, of which molecular constants were determined for the first time.