Possible AAC stacking rate improvements

This work has been triggered by a seminar given at CERN on collider concepts for high energies where, for a $Z^{0}$ factory or a proton/antiproton collider, a luminosity of 10$^{33}$ cm$^{-2}$ s$^{-1}$ is required. Improvements of the anti proton production and cooling rate are reviewed and quantitatively estimated with the basic assumption that no drastic change would be made in the fundamental design.