Comparison between the simulated and measured luminosity performance of CESR

In order to understand and optimize the luminosity of the Cornell Electron Storage Ring (CESR), a combined program of accelerator measurements and numerical simulation studies was undertaken during 1985 and early 1986. The results of the investigation of a number of particular subjects are reported: (1) Agreement between the simulated and measured beam current dependence of luminosity near the standard CESR operating point. (2) The effects on luminosity of chromaticity and the pattern of sextupole strengths. (3) The occurrence of asymmetric e+e- beam heights, ''beam flipping'', in both CESR and simulation results. (4) A tune plane scan performed with the simulation where a factor of two increase in luminosity was predicted at low vertical tune. CESR experiments revealed no such improvement due to the excitation of vertical coherent modes at multiples of the synchrotron frequency. Including single beam synchrobetatron coupling in an approximate manner improved agreement between the simulation and CESR