Further results and evaluation of electron cooling experiments at LEAR

Abstract First electron cooling experiments were performed with 10 7 to 2×10 9 stored antiprotons of 50, 21 and 6 MeV at the Low Energy Antiproton Ring (LEAR) at CERN. Most effort was put into the study of the longitudinal cooling. Schottky pick-up signals were used to measure the equilibrium momentum spread and the longitudinal cooling time. From the equilibrium between stochastic heating and electron cooling the longitudinal friction force in the low 10 3 m/s relative velocity range could be deduced. This method was used also to increase the cooling force by improving the alignment between the antiproton and the electron beam. Some of the experimental data are compared with results of a simulation program for electron cooling (SPEC).