Optimizing a nonlinear collimation system for future linear colliders

A possible collimation scheme is presented for a TeV linear collider which employs mechanical collimation for the horizontal plane and nonlinear collimation (scheme with skew sextupole pairs) for the vertical. This design satisfies all of the requirements imposed on collimation systems, including effective collimation of transverse energy tails, control of wakefield effects, protection of scrapers, and control of geometric and chromatic aberrations. The stability tolerances at the scrapers and sextupoles are similar to those occurring in the NLC (nonlinear collimation) final focus system; given the precision of the beam position monitors envisioned for an NLC, these tolerances should not rule out nonlinear collimation as a candidate for beam scraping in a future linear collider.<>