Recent Experience with Antiproton Cooling

Improvement of transverse stochastic cooling in cases where the pick-up-to-kicker distance is not optimal may be obtained by using a transmission-line filter that causes opposite phase shift at alternating Schottky sidebands. Improvement of the horizontal stack-core cooling in the Antiproton Accumulator by using a pickup at a zero dispersion location is planned; the filter technique will make this possible. The improvement of the signal-to-noise ratio in the 250-500 MHz stack tail termination resistors is discussed, as well as some problems caused by undesired modes perturbing the pickup response.