Dielectric Collimators for Beam Delivery Systems*

Abstract Wakefield generation by the collimation system is known to be a critical linear collider design issue. Optimization of the collimators represents a tradeoff between beam quality (halo reduction) and luminosity reduction. The primary objective is to reduce both short range (resonant) and long range (resistive) deflecting wakefields from collimators that reduce the luminosity of the machine. We consider the CLIC BDS (beam delivery system) and examine the potential for using dielectric rather than highly conducting materials for collimation. We present some examples of the flexibility gained by having control over the permittivity and conductivity of the collimator. We discuss simulation …