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Steier, C.

  
Paper Title Page
MOPKF071 Study of Row Phase Dependent Skew Quadrupole Fields in Apple-II type EPUs at the ALS 479
 
  • C. Steier, S. Marks, S. Prestemon, D. Robin, R.D. Schlueter, A. Wolski
    LBNL, Berkeley, California
 
  Since about 5 years, Apple-II type Elliptically Polarizing Undulators (EPU) have been used very successfully at the ALS to generate high brightness photon beams with arbitrary polarization. However, both EPUs installed so far cause significant changes of the vertical beamsize, especially when the row phase is changed to change the polarization of the photons emitted. The effect has been measured in detail and turned out to be caused by a row phase dependent skew quadrupole term in the EPUs. Magnetic measurements revealed the same effect for the third EPU to be installed later this year. All measurements to identify and quantify the effect with beam will be presented, as well as results of magnetic bench measurements and numeric field simulations.  
THPLT141 Operational Experience Integrating Slow and Fast Orbit Feedbacks at the ALS 2783
 
  • C. Steier, E.E. Domning, T. Scarvie, E. Williams
    LBNL, Berkeley, California
 
  A fast global orbit feedback system has been implemented at the ALS and is being used during user operation since this year. The system has two main purposes. The first is to meet the demands of some users for even improved (submicron) short term orbit stability. The second is to enable the use of more sophisticated insertion device compensation schemes (e.g. tune, beta-beating, coupling) for fast moving insertion devices like elliptically polarizing undulators, without deteriorating the orbit stability. The experience of routine user operation with the fast orbit feedback will be presented, as well as the overall feedback performance and how the integration issues with the already existing slow orbit feedback were solved.  
MOPLT143 Results and Plans of the PEP-II B-Factory 875
 
  • J. Seeman, J. Browne, Y. Cai, S. Colocho, F.-J. Decker, M.H. Donald, S. Ecklund, R.A. Erickson, A.S. Fisher, J.D. Fox, S.A. Heifets, R.H. Iverson, A. Kulikov, A. Novokhatski, M.T.F. Pivi, M.C. Ross, P. Schuh, T.J. Smith, K. Sonnad, M. Stanek, M.K. Sullivan, P. Tenenbaum, D. Teytelman, J.L. Turner, D. Van Winkle, U. Wienands, M. Woodley, Y.T. Yan, G. Yocky
    SLAC, Menlo Park, California
  • M.E. Biagini
    INFN/LNF, Frascati (Roma)
  • J.N. Corlett, C. Steier, A. Wolski, M.S. Zisman
    LBNL, Berkeley, California
  • W. Kozanecki
    CEA/DSM/DAPNIA, Gif-sur-Yvette
  • G. Wormser
    IPN, Orsay
 
  PEP-II is an e+e- B-Factory Collider located at SLAC operating at the Upsilon 4S resonance. PEP-II has delivered, over the past four years, an integrated luminosity to the BaBar detector of over 175 fb-1 and has reached a luminosity over 7.4x1033/cm2/s. Steady progress is being made in reaching higher luminosity. The goal over the next few years is to reach a luminosity of at least 2x1034/cm2/s. The accelerator physics issues being addressed in PEP-II to reach this goal include the electron cloud instability, beam-beam effects, parasitic beam-beam effects, trickle injection, high RF beam loading, lower beta y*, interaction region operation, and coupling control.  
THPKF076 Plan to Upgrade the Advanced Light Source to Top-off Injection Operation 2439
 
  • D. Robin, B. J. Bailey, K.M. Baptiste, W. Barry, E. Byrne, J.-Y. Jung, S. Kwiatkowski, R.S. Mueller, H. Nishimura, S. Prestemon, S.L. Rossi, F. Sannibale, D. Schlueter, D. Shuman, C. Steier, G.D. Stover, T. Warwick
    LBNL, Berkeley, California
  • R.J. Donahue
    LBNL/ALS, Berkeley, California
 
  The brightness and thermal stability of the Advanced Light Source (ALS) is lifetime limited. Brightness improvements such as narrower gap insertion devices, smaller emittance coupling, and higher currents all result in short lifetimes. In addition current changes over a fill impact the thermal stability of both the storage ring and beamlines. In order to mitigate these limitations there is a plan to upgrade the injector of the ALS to full energy injection and to operate in a quasi-continuous filling (Top-Off) injection operation. With Top-Off, the ALS will increase its time-averaged current by two, reduce the vertical emmittance, and operate with smaller gap insertion devices. In this paper we describe our upgrade plan.  
TUPLT153 Orbit Response Matrix Analysis Applied at PEP-II 1488
 
  • C. Steier, A. Wolski
    LBNL/AFR, Berkeley, California
  • S. Ecklund, J.A. Safranek, P. Tenenbaum, A. Terebilo, J.L. Turner, G. Yocky
    SLAC, Menlo Park, California
 
  Beam-based techniques to study lattice properties have proven to be a very powerful tool to optimize the performance of storage rings. The analysis of orbit response matrices has been used very successfully to measure and correct the gradient and skew gradient distribution in many accelerators. The first applications were mostly in synchrotron light sources, but the technique is also used increasingly at colliders. It allows determination of an accurately calibrated model of the coupled machine lattice, which then can be used to calculate the corrections necessary to improve coupling, dynamic aperture and ultimately luminosity. At PEP-II, the Matlab version of LOCO has been used to analyze coupled response matrices for both the LER and the HER. The large number of elements in PEP-II and the very complicated interaction region present unique challenges to the data analysis. The orbit response matrix analysis will be presented in detail, as well as results of lattice corrections based on the calibrated machine model.  
THOACH01 SPEAR3 Commissioning 216
 
  • J.A. Safranek, S. Allison, P. Bellomo, W.J. Corbett, M. Cornacchia, E. Guerra, R.O. Hettel, D. Keeley, N. Kurita, D.J. Martin, P.A. McIntosh, H. Morales, G.J. Portmann, F.S. Rafael, H. Rarback, J.J. Sebek, T. Straumann, A. Terebilo, J. Wachter, C. Wermelskirchen, M. Widmeyer, R. Yotam
    SLAC/SSRL, Menlo Park, California
  • M.J. Boland, Y.E. Tan
    ASP, Melbourne
  • J.M. Byrd, D. Robin, T. Scarvie, C. Steier
    LBNL/ALS, Berkeley, California
  • M. Böge
    PSI, Villigen
  • H.-P. Chang, C.-C. Kuo, H.-J. Tsai
    NSRRC, Hsinchu
  • W. Decking
    DESY, Hamburg
  • M.G. Fedurin, P. Jines
    LSU/CAMD, Baton Rouge, Louisiana
  • K. Harkay, V. Sajaev
    ANL/APS, Argonne, Illinois
  • S. Krinsky, B. Podobedov
    BNL/NSLS, Upton, Long Island, New York
  • L.S. Nadolski
    SOLEIL, Gif-sur-Yvette
  • A. Ropert
    ESRF, Grenoble
  • M. Yoon
    POSTECH, Pohang, Kyungbuk
 
  Starting in April, 2003, the SPEAR2 storage ring was removed and replaced with a new 500 mA, 3 GeV light source, SPEAR3. The SPEAR2 storage ring had been in use for high energy physics, then synchrotron radiation since 1972. Commissioning of SPEAR3 started on December 8, 2003 and synchrotron radiation will be delivered to the first users on March 8, 2004. SPEAR3 commissioning will be reviewed, including discussion of diagnostics, orbit control, optics correction and high current studies.  
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