EPAC 2004 - List of Authors

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Woodley, M.

Paper	Title	Page
MOZCH02	Start to End Simulations of Low Emittance Tuning and Stabilization	31
	P. Tenenbaum, A. Seryi, M. Woodley SLAC, Menlo Park, California D. Schulte CERN, Geneva N.J. Walker DESY, Hamburg G.R. White Queen Mary University of London, London
	The principal beam dynamics challenge to the subsystems between the damping ring and the collision point of future linear colliders is expected to be the tuning and stabilization required to preserve the transverse emittance and to collide nanometer-scale beams. Recent efforts have focused on realistically modelling the operation and tuning of this region, dubbed the Low Emittance Transport (LET). We report on the development of simulation codes which permit integrated simulation of this complex region, and on early results of these simulations. Future directions of LET simulation are also revealed.
	Video of talk
	Transparencies
MOOCH01	Beam Based Alignment at the KEK-ATF Damping Ring	36
	M. Woodley, J. Nelson, M.C. Ross, J.L. Turner SLAC, Menlo Park, California K. Kubo KEK, Ibaraki A. Wolski LBNL/AFR, Berkeley, California
	The damping rings for a future linear collider will have demanding alignment and stability requirements in order to achieve the low vertical emittance necessary for high luminosity. The Accelerator Test Facility (ATF) at KEK has successfully demonstrated the <5 pm vertical emittance specified for the GLC/NLC Main Damping Rings []. One contribution to this accomplishment has been the use of Beam Based Alignment (BBA) techniques. The mode of operation of the ATF presents particular challenges for BBA, and we describe here how we have deduced the offsets of the BPMs with respect to the quadrupoles. We also discuss a technique that allows for direct measurements of the beam-to-quad offsets. "Extremely Low Vertical-Emittance Beam in the Accelerator Test Facility at KEK", K. Kubo, et al., Phys.Rev.Lett.88:194801,2002
	Video of talk
	Transparencies
MOPLT137	Beam Delivery Layout for the Next Linear Collider	860
	A. Seryi, Y. Nosochkov, M. Woodley SLAC, Menlo Park, California
	We present the latest design and layout of the NLC Beam Delivery System (BDS) for the first and second interaction region (IR). This includes the beam switchyard, skew correction and emittance diagnostics section, collimation system integrated with the final focus, the primary and post linac tune-up beam dumps, and arcs of the second interaction region beamline. The layout and optics are optimized to deliver the design luminosity in the entire energy range from 90GeV to 1.3TeV CM, with the first IR BDS also having the capabilities for multi-TeV extension.
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.
THPLT156	Simulations of IP Feedback and Stabilization in the NLC	2822
	L. Hendrickson, J.C. Frisch, T.M. Himel, T.O. Raubenheimer, A. Seryi, M. Woodley SLAC, Menlo Park, California G.R. White Queen Mary University of London, London
	Keeping nanometer-sized beams in collision is an essential component in achieving design luminosity in a linear collider. The NLC stabilization strategy is conservative by including enough redundancy so that if some piece doesn't work to specification or the incoming beam motion is worse than expected, the beams will still be kept in collision. We show simulation results with both realistic and pessimistic assumptions about the response of the ground motion, inertial stabilization, interbunch and intertrain feedback systems. By providing backup systems, and by assuming that some systems may perform more poorly than expected, we can achieve a high level of confidence in our ability to successfully stabilize the beams.
THPLT157	Beam-based Feedback for the NLC Linac	2825
	L. Hendrickson, N. Phinney, A. Seryi, P. Tenenbaum, M. Woodley SLAC, Menlo Park, California
	The NLC linac train-by-train feedback system is designed to stabilize the beam trajectory, but is also a valuable element in the strategy for emittance preservation. New simulations employ improved strategies [], allowing beam steering to be performed significantly less often than without the feedback system. Additional simulations indicate that the linac feedback can contribute towards successful operation at noisier sites. Beam-based Feedback Simulations for the NLC Linac, L. Hendrickson et al., LINAC, Monterey, California (2000)
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.
MOPLT142	Analysis of KEK-ATF Optics and Coupling Using LOCO	872
	M. Woodley, J. Nelson, M.C. Ross SLAC/NLC, Menlo Park, California A. Wolski LBNL/AFR, Berkeley, California
	LOCO is a computer code for analysis of the linear optics in a storage ring based on the closed orbit response to steering magnets. The analysis provides information on focusing errors, BPM gain and rotation errors, and local coupling. Here, we discuss the details of the LOCO implementation at the KEK-ATF Damping Ring, and report the initial results. Some of the information obtained, for example on the BPM gain and coupling errors, has not previously been determined. We discuss the possibility of using the data provided by the LOCO analysis to reduce the vertical emittance of the ATF beam.
TUPLT161	Normal Form Analysis of Linear Beam Dynamics in a Coupled Storage Ring	1503
	M. Woodley SLAC/NLC, Menlo Park, California A. Wolski LBNL/AFR, Berkeley, California
	The techniques of normal form analysis, well known in the literature, can be used to provide a straightforward characterization of linear betatron dynamics in a coupled lattice. Here, we consider both the beam distribution and the betatron oscillations in a storage ring. We find that the beta functions for uncoupled motion generalize in a simple way to the coupled case. Defined in the way that we propose, the beta functions remain well behaved (positive and finite) under all circumstances, and have essentially the same physical significance for the beam size and betatron oscillations as in the uncoupled case. Application of this analysis to the online modeling of the PEP-II rings is also discussed.