Darmstadt 2008 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

A: Fachverband Atomphysik

A 14: Posters: Interaction of matter with ions

A 14.6: Poster

Tuesday, March 11, 2008, 16:30–18:30, Poster C3

Cross sections for antiproton collisions — •Armin Lühr and Alejandro Saenz — Humboldt-Universität zu Berlin, Institut für Physik, Moderne Optik, Hausvogteiplatz 5-7, D-10117 Berlin

In the near future the conditions for the production of slow antiproton beams will strongly improve with the upcoming low energy antiproton facility FLAIR at the GSI Darmstadt. This provides on the one hand the basis for fundamental physics like tests of the CPT-invariance or gravity of antimater. However, under these conditions investigations of antiproton collisions at energies below the applicability of the first Born approximation will also be possible. Therefore, new impetus is given to theoretical investigations dealing with slow antiproton collisions. The calculations should in turn also be useful for the design of the new experimental facility where, e.g., the interaction of antiprotons with residual-gas atoms is important.

Theoretical investigations for collisions of the alkali metal atoms Li, Na and K with antiprotons in an energy range from 0.2 to 1000 keV have been performed. Cross sections for excitation, ionization and angular resolved ionization are presented. The calculations are based on a time-dependent close coupling method. The valence electron is treated explicitly while the closed-shell electrons are described by an effective Klappisch potential. The classical trajectory approximation has been used. The method used so far is currently extended from atomic to molecular targets. First results for antiproton collisions with molecular hydrogen are presented.