Bonn 2000 – scientific programme
Parts | Days | Selection | Search | Downloads | Help
A: Atomphysik
A 15: Poster I
A 15.5: Poster
Wednesday, April 5, 2000, 10:30–13:00, Aula
Associative detachment in low energy collisions between atomic negative halogen ions and hydrogen atoms⋆ — •F.A.U. Thiel2, M. Cízek1, H. Hotop2, and J. Horácek1 — 1Department of Theoretical Physics, Charles University Prague, 180 00 Praha 8, Czech Republic — 2Department of Physics, University of Kaiserslautern, D-67663 Kaiserslautern, Germany
Total cross sections and electron spectra for low energy associative detachment collisions between atomic negative halogen ions X− (X = F, Cl and Br) and hydrogen atoms have been calculated, using an improved nonlocal resonance model. The model involves realistic long-range interactions for the X− + H systems and takes the dependence of the dipole-modified treshold exponent on the internuclear distance into account. Good overall agreement is found between the existing experimental data for the total cross sections and the theoretical results. In the calculated electron energy spectra nonlocal effects are manifest through cusp structures which are (almost) independent of the collision energy; these structures should therefore be observable in experiments with rather modest energy resolution. For illustration, electron spectra are presented which correspond to realistic experimental conditions with regard to the energy widths of the electron spectrometer and the collision energy distribution.
⋆ This work has been supported by the Deutsche Forschungsgemeinschaft.