Beams of 46 MeV protons have been cooled by means of electrons in the ICE (initial cooling experiment) storage ring. Six two-day runs starting in May 1979 have shown, for proton intensities of up to 3 × 108, a density increase in six dimensional phase space of over a factor of 106, with cooling times in momentum spread and betatron amplitudes of 0.3 and 1.2 s, respectively. The proton beam lifetime was increased by a factor of 40. Measurements of the evolution of momentum spread, beam profile, and neutral atom production rate are in reasonable agreement with theory. © 1979.
