AP-Seminar: Electron impact ionization of clusters and molecules

 Kinematically complete experiments on electron impact ionization give detailed insight into the scattering process and critically test ab-initio calculations. Particularly interesting and challenging are studies for complex targets like molecules and clusters. Using an advanced reaction microscope we have acquired fully differential cross-sections for such species covering the complete solid angle of electron and ion emission. A few exemplary studies will be presented: For ionization of H₂ a strong dependence of the collision dynamics on the spatial alignment of the target molecules is observed. Collisions involving small noble gas clusters reveal multiple scattering processes and various cluster dissociation mechanisms. Finally, for more complex molecules like CH₄ we demonstrate how the measurement of the kinematic energies of the ionic fragments and the final state electrons allows to disentangle the molecular states involved in the dissociation process.