D. Teytelman

Progress of the PEP-II B-factory

PEP-II is an e/sup +/e/sup -/ B-factory collider located at SLAC operating at the Upsilon 4S resonance. PEP-II has delivered, over the past five years, an integrated luminosity to the BaBar detector of over 131 fb/sup -1/ and has reached a luminosity of 6.11/spl times/10/sup 36//cm/sup 2//s. Steady progress is being made in reaching higher luminosity. The goal over the next several years is to reach a luminosity of at least 2/spl times/10/sup 34//cm/sup 2//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, high RF beam loading, shorter bunches, lower betay*, interaction region operation, and coupling control. The present parameters of the PEP-II B-Factory are compared to the design. The present peak luminosity is 204% of design and the best integrated luminosity per month is 7.4 fb/sup -1/ that is 225% of design. The progress in luminosity has come from correcting the orbits, adding specific orbit bumps to correct coupling and dispersion issues, lowering the betay* in the LER, and moving the fractional horizontal tunes in both rings to just above the half integer (<0.52).

Effect of the Coupled-bunch Modes on the Longitudinal Feedback System

The Pedersen analysis [1, 2] of the low-level rf feedback system assumes that all bunches oscillate in phase what corresponds to the lowest coupled bunch mode. This analysis is extended here to take into account all other coupled-bunch modes what might be important for the strongly detuned cavities in large storage rings such as PEP-II.

Design studies for a 10/sup 36/ Super-B-factory

A Super B factory, an asymmetric e/sup +/e/sup -/ collider with a luminosity of 10/sup 36/ cm/sup -2/s/sup -1/, can provide a sensitive probe of new physics in the flavor sector of the standard model. The success of PEP-II and KEKB in producing unprecedented luminosity with unprecedently short commissioning time has taught us about the accelerator physics of asymmetric e/sup +/e/sup -/ colliders in a new parameter regime. It appears to be possible to build on this success to advance the state of the accelerator art by building a collider at a luminosity approaching 10/sup 36/ cm/sup -2/s/sup -1/. Such a collider would produce an integrated luminosity of 10,000 fb/sup -1/ (10 ab/sup -1/) in a running year. Design studies are underway to arrive at a complete parameter set based on a collider in the PEP-II tunnel but with an upgraded RF system (perhaps a higher frequency) and an upgraded interaction region.