COLLIMATION SYSTEMS FOR A TEV LINEAR COLLIDER

Experience with the SLAG Linear Collider (SLC) has indicated that back grounds caused by the transverse and energy tails of the beam distribu tion will be a serious problem for a next-generation linear collider. At small emittances mechanical scrapers do not provide a solution, bec ause they can be damaged by the tiny, intense beams, and also because they induce wakefield kicks which cause emittance dilution. In this pa per, we present a possible solution which uses several nonlinear lense s to drive beam tails to large amplitudes where they can be more easil y scraped mechanically. We present a design for transverse and energy collimation and study the optimization of such systems including wakef ield effects and optical aberrations. Protection and design of the scr apers are discussed.