• Y. Cai, Y. Nosochkov
  SLAC, Menlo Park, California

The leading Lie generators, including the chromatic effects, due to hard edge fringe field of single multipole and solenoid are derived from the vector potentials within a Halmitonian system. These nonlinear generators are applied to the interaction region of PEP-II to analyze the linear errors due to the feed-down from the off-centered quadrupoles and solenoid. The nonlinear effects of tune shifts at large amplitude, the synchro-betatron sidebands near half integer and their impacts on the dynamic aperture are studied in the paper.

• B. Parker, M. Anerella, J. Escallier, M. Harrison, P. He, A.K. Jain, A. Marone, K.-C. Wu
  BNL, Upton, Long Island, New York
• T.W. Markiewicz, T.V.M. Maruyama, Y. Nosochkov, A. Seryi
  SLAC, Menlo Park, California

We present a compact superconducting final focus (FF) magnet system for the ILC based on recent BNL direct wind technology developments. Direct wind gives an integrated coil prestress solution for small transverse size coils. With beam crossing angles more than 15 mr, disrupted beam from the IP passes outside the coil while incoming beam is strongly focused. A superconducting FF magnet is adjustable to accommodate collision energy changes, i.e. energy scans and low energy calibration runs. A separate extraction line permits optimization of post IP beam diagnostics. Direct wind construction allows adding separate coils of arbitrary multipolarity (such as sextupole coils for local chromaticity correction). In our simplest coil geometry extracted beam sees significant fringe field. Since the fringe field affects the extracted beam, we also study advanced configurations that give either dramatic fringe field reduction (especially critical for gamma-gamma colliders) or useful quadrupole focusing on the outgoing beam channel. We present prototype coil winding test results and discuss our progress toward an integrated FF solution that addresses important machine detector interface issues.

• Y. Nosochkov, K. C. Moffeit, A. Seryi, M. Woods
  SLAC, Menlo Park, California
• R. Arnold
  University of Massachusetts, Amherst
• W.P. Oliver
  Tufts University, Medford, Massachusetts
• B. Parker
  BNL, Upton, Long Island, New York
• E.T. Torrence
  University of Oregon, Eugene, Oregon

One of the two ILC Interaction Regions will have a large horizontal crossing angle which would allow to extract the spent beams in a separate beam line. In this paper, the extraction line design for 20 mrad crossing angle is presented. This beam line transports the primary e+/e^- and beamstrahlung photon beams from the IP to a common dump, and includes diagnostic section for energy and polarization measurements. The optics is designed for a large energy acceptance to minimize losses in the low energy tail of the disrupted beam. The extraction optics, diagnostic instrumentation and particle tracking simulations are described.