Targetry Used on the Bevatron to Extract Secondary Experimental Beams

This paper briefly covers development of target drive mechanisms at the Bevatron, with the final evolution of the present high-speed mechanism. The early target drives, used in the main circulating beam channel, could raise a 1-lb target head 5-1/2 in. in 100 ms. The present high-speed target drive is designed to raise a 1/2-lb target head 1-1/2 in. in 10 ms. The higher-speed mechanism became desirable with increased beam control, allowing for flat topping and splitting individual Bevatron beam pulses between two or more experimenters. All designs are intended for performance in the high vacuum of the accelerating chamber.