PROJECT DESCRIPTION Study of Space Charge Effects in the International Linear Collider Damping Rings

Indispensable subsystems of the International Linear Collider (ILC) will be the damping rings, which will shrink the emittances of the electron and positron beams. This idea was first proposed by Amaldi [1]. Once the beams enter their respective main linacs, the ultra low emittances should already have been achieved in the damping rings, where the equilibrium emittances are determined by the balancing of a variety of effects, including radiation damping, quantum excitations, intrabeam scattering, gas ions in the electron ring, electron clouds in the positron ring, and of particular interest for this project, space charge. Recently, there have been alternatives proposed for the damping rings baseline configuration that were derived from a number of studies of seven reference lattices covering a range of beam parameter options, with circumferences ranging from roughly 3 to 17 km and energies from 3.74 to 5.066 GeV [2]. Thus, a major task continues to be to compare the impact of as many effects as possible on the various reference lattices.