Recent SLC developments

The SLAC Linear Collider (SLC) is the forerunner of a new generation of high energy accelerators. As such, it incorporates many novel features that must be fully exploited to achieve optimum performance. In this paper we present an overview of the frontiers of collider performance at SLC. Recent developments have centered on polarization, intensity and emittance preservation issues. A polarized source and spin transport system were successfully commissioned in 1992 and operated with high reliability. Practical intensity limits associated with rapid growth (<τS) bunch length instabilities have been observed in the damping rings. Ring RF voltage manipulations are used to suppress the instabilities. Emittance preservation technique development has focused on controlling system-wide instabilities and improving feedback and tuning procedures. Control of instabilities of all time scales, pulse to pulse, fast and slow, is one of the most challenging aspects of the collider. The challenge is met with (1) very high level of control and automation required for general tuning and optimization, (2) real-time transport line optical correction and monitoring, (3) coupled, high level, trajectory and energy feedback, (4) high order multipole optical correction and monitoring, (5) feedback-based linac beam emittance preservation, and (6) interaction region luminosity optimization. The common thread beneath all of these is the SLC control system which must provide a level of control, diagnosis and feedback not required for simpler machines