Comparison of measurements and simulations of internal target effects in the ESR storage ring

A proper description of beam-target effects is necessary to predict the operation conditions for high beam luminosity and quality. In order to evaluate the beam dynamics in the storage ring, where cooling in combination with a dense target is applied, a number of numerical models have been developed. Systematic benchmarking experiments were carried out with different gases in the gas-jet target at the existing ESR storage ring at GSI. The influence of the internal target on the beam parameters was investigated. Comparison of the measurements with an analytical formula for the energy loss due to the target as well as with more sophisticated simulations with the BETACOOL code will be given.