Minimizing RF system costs in a linear collider by an optimized choice of beam and structure parameters

In the design of future linear colliders it will be important to reduce the cost of the RF system by minimizing the total number of major system components (klystrons, modulators and pulse compression systems). In this paper we develop a procedure for performing this minimization by varying appropriate accelerating structure and beam parameters while maintaining a constant luminosity, AC "wall-plug" power and net beam-loaded accelerating gradient. Results for both standing-wave and traveling-wave accelerator structures are presented, including the plane-wave transformer and more conventional disk-loaded structures having cells with shaped (as opposed to purely cylindrical) outer boundaries and irises.