• Y. Nosochkov, W. Wittmer
  SLAC, Menlo Park, California
• M.E. Biagini, P. Raimondi
  INFN/LNF, Frascati (Roma)
• P.A. Piminov, S.V. Sinyatkin
  BINP SB RAS, Novosibirsk

The Super-B asymmetric e⁺e^- collider is designed for 10³⁶ cm^-2sec^-1 luminosity and beam energies of 6.7 and 4.18 GeV for e⁺ and e-, respectively. The machine will have the High and Low Energy Rings (HER and LER), and one Interaction Point (IP) with 60 mrad crossing angle. The INFN-LNF at Frascati is one of the proposed sites, and a lattice for short 1.3 km rings fitting to this site has been designed. The two rings are radially separated by 2 m except near the IP and in the dogleg on the opposite side of the rings. The injection sections and RF cavities are included. The lattice is optimized for a low emittance required for the desired high luminosity. Final Focus chromaticity correction is optimized for large transverse and energy acceptance. The "crab waist" sextupoles are included for suppression of betatron resonances induced at the IP collisions with large Piwinski angle. The LER spin rotator sections provide longitudinal polarization for the electron beam at IP. The lattice is flexible for tuning the design parameters and compatible with reusing the PEP-II magnets, RF cavities and other components. Design criteria and details on the lattice implementation are presented.

• U. Wienands, Y. Nosochkov, M.K. Sullivan, W. Wittmer
  SLAC, Menlo Park, California
• D.P. Barber
  Cockcroft Institute, Warrington, Cheshire
• M.E. Biagini, P. Raimondi
  INFN/LNF, Frascati (Roma)
• I. Koop, S.A. Nikitin, S.V. Sinyatkin
  BINP SB RAS, Novosibirsk

The availability of longitudinally polarized electrons is an important aspect of the design of the proposed SuperB project at LNF Frascati. Spin rotators are an integral part of the design of the Interaction Region (IR). We have chosen a solenoid-dipole design; at the 4.18 GeV nominal energy this is more compact that a design purely based on dipole magnets. Integration with the local chromaticity correction of the ultra-low beta* IR has been achieved. The spin rotators are symmetric about the Interaction Point, this design saves a significant amount of length as the dipoles become a part of the overall 360 deg. bend. The layout leaves limited opportunity to setup the optics for minimum depolarization; this is acceptable since beam life time in SuperB at high luminosity is only about 5 min and up-to 90% polarized electrons will be injected continuously. In this way an average beam polarization of about 70% is maintained. Simulations and analytic estimates with the DESY code SLICKTRACK and other codes indicate such operation is feasible from a spin-dynamics point of view. The paper will discuss the overall spin-rotator design as well as the spin dynamics in the ring.

• M.E. Biagini, D. Alesini, R. Boni, M. Boscolo, T. Demma, A. Drago, M. Esposito, S. Guiducci, F. Marcellini, G. Mazzitelli, M.A. Preger, P. Raimondi, C. Sanelli, M. Serio, A. Stecchi, A. Stella, S. Tomassini, M. Zobov
  INFN/LNF, Frascati (Roma)
• M.A. Baylac, J.-M. De Conto, Y. Gomez-Martinez, N. Monseu, D. Tourres
  LPSC, Grenoble
• K.J. Bertsche, A. Brachmann, Y. Cai, A. Chao, M.H. Donald, A.S. Fisher, D. Kharakh, A. Krasnykh, N. Li, D.B. MacFarlane, Y. Nosochkov, A. Novokhatski, M.T.F. Pivi, J. Seeman, M.K. Sullivan, A.W. Weidemann, J. Weisend, U. Wienands, W. Wittmer, A.C. de Lira
  SLAC, Menlo Park, California
• S. Bettoni
  CERN, Geneva
• B. Bolzon, L. Brunetti, A. Jeremie
  IN2P3-LAPP, Annecy-le-Vieux
• J. Bonis, G. Le Meur, B.M. Mercier, F. Poirier, C. Prevost, C. Rimbault, F. Touze, A. Variola
  LAL, Orsay
• F. Bosi
  INFN-Pisa, Pisa
• A. Chancé, F. Méot, O. Napoly
  CEA, Gif-sur-Yvette
• R. Chehab
  IN2P3 IPNL, Villeurbanne
• I. Koop, E.B. Levichev, S.A. Nikitin, P.A. Piminov, D.N. Shatilov, S.V. Sinyatkin
  BINP SB RAS, Novosibirsk
• S.M. Liuzzo, E. Paoloni
  University of Pisa and INFN, Pisa

The SuperB project is an international effort aiming at building in Italy a very high luminosity e⁺e^- (10³⁶ cm^-2 sec^-1) asymmetric collider at the B mesons cm energy. The accelerator design has been extensively studied and changed during the past year. The present design, - based on the new collision scheme, with large Piwinski angle and the use of 'crab' sextupoles, which has been successfully tested at the DAPHNE Phi-Factory at LNF Frascati, - provides larger flexibility, better dynamic aperture and in the Low Energy Ring spin manipulation sections, needed for having longitudinal polarization of the electron beam at the Interaction Point. The Interaction Region has been further optimized in terms of apertures and reduced backgrounds in the detector. The injector complex design has been also updated. A summary of the design status, including details on lattice and spin manipulation will be presented in this paper.

• Y. Papaphilippou, F. Antoniou, M.J. Barnes, S. Bettoni, S. Calatroni, P. Chiggiato, R. Corsini, A. Grudiev, R. Maccaferri, M. Modena, L. Rinolfi, G. Rumolo, D. Schoerling, D. Schulte, M. Taborelli, A. Vivoli
  CERN, Geneva
• E.B. Levichev, S.V. Sinyatkin, P. Vobly, K. Zolotarev
  BINP SB RAS, Novosibirsk

The CLIC damping rings should produce the ultra-low emittance necessary for the high luminosity performance of the collider. This combined to the high bunch charge present a number of beam dynamics and technical challenges for the rings. Lattice studies have been focused on low emittance cells with optics that reduce the effect Intra-beam scattering. The final beam emittance is reached with the help of super-conducting damping wigglers. Results from recent simulations and prototype measurements are presented, including a detailed absorption scheme design. Collective effects such as electron cloud and fast ion instability can severely limit the performance and mitigation techniques have been identified and tested. Tolerances for alignment and technical system design such as kickers, RF cavities, magnets and vacuum have been finally established.