Branching ratios in dissociative recombination of the C2H2+molecular ion

Branching ratios in dissociative recombination of C2H2+ molecular ions with electrons were measured using the CRYRING heavy-ion storage ring. We have determined complete branching ratios for C2H2+ at collision energies between 0 and 7.4 meV. We found dissociative recombination of C2H2+ to be dominated by the two-body C2H+H and three-body C2+H+H channels, with branching ratios of 0.50±0.06 and 0.30±0.05, respectively. The branching to CH+CH was measured to be 0.13±0.01, whereas two other energetically allowed channels were found to be almost negligible.