Potential accelerator improvements required for the Tevatron upgrade at Fermilab

A considerable amount of effort has been dedicated toward understanding what accelerator improvements are required to reach a luminosity per detector exceeding 10³³ cm^-2 sec ^-1 at Fermilab. This effort has been popularly named the Tevatron33 project. Collider issues involve long range beam-beam interactions between the 100 or more bunches per beam traveling along separated helical orbits, the necessity of crossing angles at the interaction points, and beam instabilities. The main challenge of the injector chain is to produce more antiprotons at a faster rate. One potential improvement would be to configure the modified antiproton source to recycle the antiprotons left over at the end of each collider store. In this paper the current plan for implementing the Tevatron33 upgrade is reviewed