PAC 2005 - List of Authors

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Fisher, A.S.

Paper	Title	Page
TPPP026	Bunch-Length Measurements in PEP-II	1934
	A.S. Fisher, A. Novokhatski, J.L. Turner, U. Wienands, G. Yocky SLAC, Menlo Park, California R. Holtzapple Alfred University, Alfred, New York
	Funding: Supported by U.S. Department of Energy contract DE-AC03-76SF00515. We measured the lengths of colliding e⁺e^- bunches in the PEP-II B Factory at SLAC using various techniques. First, at several RF voltages and with both single-bunch and multibunch beams, a synchroscan streak camera measured synchrotron emission through a narrow blue filter. With 3.8 MV of RF, the length of a single positron bunch was 12 mm at low current, rising to 13 mm at 1.5 mA and 14.8 mm at 3 mA. The electrons measured 12.2 mm with little current dependence. Both are longer than the expected low-current value of 10 mm (e+) and 11 mm (e-), derived from the energy spread and the measured synchrotron tune. We also determined the length from measurements between 2 and 13 GHz of the bunch spectrum on a BPM button. After correcting for the frequency dependence of cable attenuation, we then fit the measured spectrum to that of a Gaussian bunch. With 3.8 MV, the positrons measurement gave 13.2 mm at 1.5 mA/bunch in a full ring, in agreement with the streak camera, but we found 11.4 mm for the electrons at 16.7 MV and 1 mA/bunch, lower than the streak measurement.
TPPP027	Single-Bunch Tune and Beam Size Measurements Along Bunch Trains in PEP-II	2006
	R. Holtzapple Alfred University, Alfred, New York D.D. Dujmic, A.S. Fisher SLAC, Menlo Park, California
	By scanning a gated camera and a gated tune monitor across the bunch pattern during normal colliding-bunch operation of PEP-II, the single-bunch tunes and beam sizes were measured simultaneously in the high and low energy storage rings of PEP-II. The measurements were made with 1561 colliding bunches in PEP-II, arranged in trains of 66 bunches, with each bunch in the train separated by 4.2 ns. The tune and beam size measurements were correlated with the current, luminosity, and specific luminosity of the bunch. The results show a vertical tune shift at the start and end of the mini-trains, a luminosity droop along the mini-train, and specific luminosity drop in the first and last bunches of the train, since they experience a different parasitic crossing on either side of the IP.
TPPP035	Performance of the PEP-II B-Factory Collider at SLAC	2369
	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, N. Li, A. Novokhatski, M.C. Ross, P. Schuh, T.J. Smith, K.G. Sonnad, M. Stanek, M.K. Sullivan, P. Tenenbaum, D. Teytelman, J.L. Turner, D. Van Winkle, M. Weaver, U. Wienands, M. Woodley, Y.T. Yan, G. Yocky SLAC, Menlo Park, California M.E. Biagini INFN/LNF, Frascati (Roma) W. Kozanecki CEA/DSM/DAPNIA, Gif-sur-Yvette C. Steier, A. Wolski LBNL, Berkeley, California G. Wormser IPN, Orsay
	Funding: Work supported by DOE contract DE-AC02-76SF00515. For the PEP-II Operation Staff: PEP-II is an asymmetric e⁺e^- collider operating at the Upsilon 4S and has recently set several performance records. The luminosity has reached 9.2 x 10³³/cm²/s. PEP-II has delivered an integrated luminosity of 710/pb in one day. It operates in continuous injection mode for both beams boosting the integrated luminosity. The peak positron current has reached 2.55 A in 1588 bunches. The total integrated luminosity since turn on in 1999 has reached 256/fb. This paper reviews the present performance issues of PEP-II and also the planned increase of luminosity in the near future to over 2 x 10³⁴/cm²/s. Upgrade details and plans are discussed.