RF feedback for beam loading compensation in the SLC Damping Rings

An RF feedback around the cavities and klystron has been added to the SLC Damping Rings to provide stability under changing beam loading conditions. The beam loading changes in the cavity as a result of programming the RF voltage during the beam store time. The RF voltage is lowered to control the onset of bunch length instabilities, but without RF feedback the beam becomes unstable in the Robinson zero frequency mode. The steady state analysis of the beam loading with and without feedback is presented together with a description of the hardware implementation. Operational experience with the system during SLC running is described.<>