Another scenario is a negative ion formation through an EA of C2H2 (reaction 25), which has been concluded to be possible by May et al., to have a sufficient cross section to enable experimental verification of e.g., C2H -, C2 -and H -. When verifying the experimental cross section of C2H2, the fragments could be seen at an energy of 2.95 eV for a dissociative electron attachment (DEA) leading to C2H -, with a cross section of. 3.6*10 -20 cm 2 . While DEA leading to C2 -showed a DEA cross section of 4.1*10 -20 cm 2 , although at an electron energies of 8.1