Fermilab, Batavia, Illinois, USA
The Fermilab Booster, which utilizes multi-turn injection and adiabatic capture, the extraction gap (aka "notch") has been created in the ring at injection energy using fast kickers which deposit the beam in a shielded absorber within the accelerator tunnel. This process, while effective at creating the extraction notch, was responsible for a significant fraction of the total beam power loss in the Booster tunnel and created significant residual activation within the Booster tunnel in the absorber region and beyond. With increasing beam demand from the Experimental Program, the Fermilab Proton Improvement Plan (PIP) initiated an R&D project to build a laser system to create the notch within a linac beam pulse at 750 keV, where activation in not an issue. This talk will discuss moving from R&D to an operational laser system and its integration into the accelerator complex. We will also cover the loss reduction in the Booster, increased efficiency, and increased proton throughput. We will touch on other potential applications for this bunch-by-bunch neutralization approach.
Fermilab, Batavia, Illinois, USA
A second harmonic RF cavity which uses perpendicularly biased garnet for frequency tuning is currently being constructed for use in the Fermilab Booster. The cavity will operate at twice the fundamental RF frequency, from ~76 - 106 MHz, and will be turned on only during injection, and transition or extraction. Its main purpose is to reduce beam loss as required by Fermilab's Proton Improvement Plan (PIP). After three years of optimization and study, the cavity design has been finalized and all constituent parts have been received. We discuss the design aspects of the cavity and its associated systems, component testing, and status of the cavity construction.