POLARIZATION SPECTROSCOPY APPLIED TO C2 DETECTION IN A FLAME

The detection of C2 radicals in a premixed acetylene-oxygen flame by u sing polarization spectroscopy is reported. The signal was recorded in the Swan system, d3PI(g)-a3PI(u) (0, 0), using a pulsed dye laser. Th e spectrum shows a very good signal-to-noise ratio with clearly resolv ed rotational structures of the P and R triplets. The dependence of th e signal on the pump-beam polarization was also studied. The spatial d istribution of the signal from C2 radicals in the flame was measured a s a demonstration of the use of polarization spectroscopy in combustio n diagnostics.