Sub-Femtosecond Correlated Dynamics Explored with Antiprotons

Ionizing collisions of antiprotons with atoms or molecules at energies between a few keV up to about one MeV provide a unique tool to explore correlated dynamics of electrons at large perturbations on a time scale between several femtoseconds (1 fs = 10−15 s) down to some tens of attoseconds (1 as = 10−18 s). Exploiting and developing many‐particle imaging methods — Reaction‐Microscopes — integrated into a novel ultra‐low energy storage ring (USR) for slow antiprotons will enable to access for the first time fully differential cross sections for single and multiple ionization in such collisions. Moreover, the formation of antiprotonic atoms, molecules or of protonium might be explored in kinematically complete experiments yielding unprecedented information on (n,l)‐distributions of captured antiprotons as well as precise spectroscopic data of the respective energy levels. In this contribution the present status on single and double ionization by antiproton and ion impact is highlighted pointing to the puzzling discrepancies between experiments and theoretical predictions. The design status of the USR as a central element of the proposed facility for low‐energy antiproton and ion research (FLAIR) at GSI will be shortly presented.