Berlin 2001 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

MO: Molekülphysik

MO 8: Posters Thursday: Dissociation and other Collision Processes

MO 8.19: Poster

Thursday, April 5, 2001, 12:30–15:00, AT3

Dissociative Electron Attachment to Hydrogen — •Thomas Fiegele, Herwig Drexel, Gilbert Senn, Paul Scheier, Aleksandar Stamatovic, Nigel Mason, and Tilmann Märk — Institut für Ionenphysik, Leopold Franzens Universität, Technikerstr. 25, 6020 Innsbruck, Austria

Using two different crossed-beams electron attachment instruments, one equipped with a trochoidal electron monochromator and one with a hemispherical, we have measured the cross section curve for H⁻ production from H₂ via the 4 eV resonance at two different temperatures. These relative partial cross sections have been calibrated by comparing present values for the 14 eV resonance with the absolute total cross sections determined previously. Taking into account the experimental energy distribution and the rotational excitation and its influence on the cross section shape [1] we obtain very good agreement with theoretical predictions in both, shape and magnitude of this resonance peak. The present data correspond best with the calculations of Hickman [2] and Gauyacq [3] and we therefore suggest that these values should be used in the modelling of hydrogen plasmas.
[1] I. Fabrikant, private communication, 1999
A.P. Hickman, Phys. Rev. A 43 (1991), 3495
J.P. Gauyacq, J. Phys. B 18 (1985), 1858