Beam-Beam Effect Simulation for a Modest Colliding-Beam Experiment at Fermilab

It has been proposed1 to get the Fermilab main ring to collide with a small proton storage ring in one of the six straight sections. Proton-proton colliding beam experiments would be carried out parasitically during the main ring ordinary acceleration cycle so that the beam could also be extracted and used in the fixed target experimental area. The performance parameters are shown in Tables 1 and 2. This hybrid operation of the main ring caused some concerns about the deterioration and the survival of the main proton beam because of the very large beam-beam tune shift. We performed numerical simulations of the motion of the main ring protons. Since the number of revolutions is relatively small we could simulate also an entire cycle of acceleration. The results: surprisingly the main ring beam can tolerate quite a large tune-shift with little deterioration, provided few precautions are taken for both beams handling.