Smith, T.J.

Paper	Title	Page
MOOCH03	Status of a Linac RF Unit Demonstration for the NLC/GLC X-band Linear Collider	42
	D.C. Schultz, C. Adolphsen, D.L. Burke, J. Chan, S. Doebert, V.A. Dolgashev, J.C. Frisch, R.K. Jobe, D.J. McCormick, C.D. Nantista, J. Nelson, M.C. Ross, T.J. Smith, S.G. Tantawi SLAC, Menlo Park, California D.P. Atkinson LLNL, Livermore, California Y.H. Chin, S. Kazakov, A. Lounine, T. Okugi, N. Toge KEK, Ibaraki
	Designs for a future TeV scale electron-positron X-band linear collider (NLC/GLC) require main linac units which produce and deliver 450 MW of rf power at 11.424 GHz to eight 60 cm accelerator structures. The design of this rf unit includes a SLED-II pulse compression system with a gain of approximately three at a compression ratio of four, followed by an overmoded transmission and distribution system. We have designed, constructed, and operated such a system as part of the 8-Pack project at SLAC. Four 50 MW X-band klystrons, running off a common 400 kV solid-state modulator, drive a dual-moded SLED-II pulse compression system. The compressed power is delivered to structures in the NLCTA beamline. Four 60 cm accelerator structures are currently installed and powered, with four additional structures and associated high power components available for installation late in 2004. We describe the layout of our system and the various high-power components which comprise it. We also present preliminary data on the processing and initial high-power operation of this system.
	Video of talk
	Transparencies
MOPLT139	Beam-based Alignment and Beta Function Measurements in PEP-II	866
	G. Yocky, J. Nelson, M.C. Ross, T.J. Smith, J.L. Turner, M. Woodley SLAC, Menlo Park, California
	Careful optics studies and stringent lattice control have been identified as two key components to increasing PEP-II luminosity. An accurate, trusted BPM system is required for both of these strategies. To validate the existing BPM system and to better understand some optical anomalies in the PEP-II rings, an aggressive program of beam-based alignment (BBA) has been initiated. Using a quad-shunt BBA procedure in which a quadrupole?s field strength is varied over a range of beam positions, relative offsets are determined by the BPM readings at which quadrupole field changes no longer induce a closed orbit shift. This procedure was verified in the HER and is well underway in the LER IR. We have found many surprisingly large BPM offsets, some over one centimeter, as well as a number of locations where the current nominal orbit is several millimeters from the quadrupole center. Tune versus quadrupole field data were taken during the BBA process in the LER IR, and the non-linear response in each case is compared to simulation to infer local beta functions.
MOPLT107	Nanosecond-timescale Intra-bunch-train Feedback for the Linear Collider: Results of the FONT2 Run	785
	P. Burrows, T. Hartin, S.M. Hussain, S. Molloy, G.R. White Queen Mary University of London, London C. Adolphsen, J.C. Frisch, L. Hendrickson, R.K. Jobe, T. Markiewicz, D.J. McCormick, J. Nelson, M.C. Ross, S. Smith, T.J. Smith SLAC, Menlo Park, California R. Barlow, M. Dufau, A. Kalinin CCLRC/DL/ASTeC, Daresbury, Warrington, Cheshire G. Myatt, C. Perry OXFORDphysics, Oxford, Oxon
	We report on experimental results from the December 2003/January 2004 data run of the Feedback On Nanosecond Timescales (FONT) experiment at the Next Linear Collider Test Accelerator at SLAC. We built a second-generation prototype intra-train beam-based feedback system incorporating beam position monitors, fast analogue signal processors, a feedback circuit, fast-risetime amplifiers and stripline kickers. We applied a novel real-time charge-normalisation scheme to account for beam current variations along the train. We used the system to correct the position of the 170 nanosecond-long bunchtrain at NLCTA, in both 'feed forward' and 'feedback' modes. We achieved a latency of 53 nanoseconds, representing a significant improvement on FONT1 (2002), and providing a demonstration of intra-train feedback for the Linear Collider.
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.