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The Advanced Photon Source injector synchrotron is a 7 GeV positron machine with a standard alternating gradient lattice. The calculated effect of dipole magnet strength errors on the orbit distortion, simulated by Monte Carlo, was reduced by sorting pairs of magnets having the closest simulated measured strengths to reduce the driving term of the integer resonance nearest the operating point. This method resulted in a factor of four average reduction in the RMS orbit distortion when all 68 magnets were sorted at once. The simulated effect of magnet measurement experimental resolution was found to limit the actual improvement. The /spl beta/-beat factors were similarly reduced by sorting the quadrupole magnets according to their gradients. >

A review is presented of stochastic cooling and electron cooling at the CRN ISR as well as at the facility at Fermilab. (AIP).

The rates of change of the adiabatic invariants are calculated in the case of Hamiltonian system subject to generalized non-conservative forces. The results are applied to the classical radiation of electrons in an accelerator or storage ring. The resulting expressions for the damping rates of three independent oscillation modes suggest structures which are damping in all three modes, while at the same time allowing “strong focussing” and the attendant strong momentum compaction.

In the course of electron cooling experiments at the Electron Cooling Ring (ECR) at Fermilab, several peculiar features of the longitudinal phase space of cold protons (200 MeV) captured in R.F. buckets were observed. Here we present the experimental facts, present a simple theory, and summarize computer simulation results which support the theory and facts. The experimental apparatus and measurement techniques have been described elsewhere. R.F. bunching was achieved with a single PPA, loaded cavity gap driven at harmonic number 6({approx} 7.56 MHz) of the revolution frequency. R.F. voltage could be developed across this gap sufficient to entirely capture even the uncooled circulating proton beam ({delta}p/p FWHM = 0.17%).