AN ENERGY RECOVERY ELECTRON LINAC-ON-PROTON RING COLLIDER

Electron-proton colliders with center of mass energies between 14 GeV and 30 GeV and luminosities at the 1033 level have been proposed recently as a means for studying hadronic structure [1]. Electron beam polarization appears to be crucial for the majority of experiments. Two accelerator design scenarios have been examined in detail: colliding rings [2] and recirculating linac-on-ring [3]. Although the linac-on-ring scenario is not as well understood as the ring-ring scenario, comparable luminosities appear feasible, while the linac-on-ring option presents a significant advantage with spin manipulations. Rf power and beam dump requirements make the linac-on-ring option viable only if the electron linac recovers the beam energy, a technolog