Spectrum of acetylene fluorescence excited by single XUV photons

Abstract

The spectrum of visible emission from photofragments of acetylene excited by single 16.85 eV photons has been recorded for the first time. The spectrum is dominated by the Swan and Deslandres-d’Azambuja bands of C2 and the 431.5 nm band of CH. The yields of these emissions are of the order 10−3 photons per absorbed incident photon. The experimental conditions suggest that the emission results from primary C*2 and CH* photofragments.