Experiments on Stochastic Cooling in ICE (Initial Cooling Experiment)

Recent experiments on stochastic cooling have resulted in cooling rates several orders of magnitude higher than obtained previously in the ISR. Two cooling systems reduce betatron oscillations. A third system reduces momentum spread, using the so-called filter method. The favourable signal-to-noise ratio of this method has led to cooling times (e-folding of peak density) of 15 s with 7.107 protons in ICE. Betatron cooling times are longer due to the lower signal-to-noise ratio. Simultaneous cooling in all three planes has yielded lifetimes of about 100 h, a value consistent with losses caused by single scattering on the residual gas. The existing stochastic cooling theory has been confirmed.