Electron cooling rates characterization at Fermilab´s Recycler

A 0.1 A, 4.3 MeV DC electron beam is routinely used to cool 8 GeV antiprotons in Fermilab´s Recycler storage ring [1]. The primary function of the electron cooler is to increase the longitudinal phase-space density of the antiprotons for storing and preparing high-density bunches for injection into the Tevatron. The longitudinal cooling rate is found to significantly depend on the transverse emittance of the antiproton beam. The paper presents the measured rates and compares them with calculations based on drag force data.