Towards Beam-Dynamics Simulations Including More Realistic Field Descriptions for the HESR

摘要

The High Energy Storage Ring (HESR) is part of the upcoming Facility for Antiproton and Ion Research (FAIR) in Darmstadt (Germany). The HESR is designed for antiprotons with a momentum range from 1.5 GeV/c to 15 GeV/c, but will as well be suitable to provide heavy ion beams with a momentum range from approximately 0.6 GeV/c to 5.8 GeV/c. To guarantee smooth operation it is crucial to verify and improve the design with beam-dynamics simulations. Particularly the dynamic aperture is calculated as a measure of quality. Complementary to previous beam dynamics calculations based on frequency map analysis [1], the dynamic aperture is calculated using a variant of the Lyapunov exponent. The first bending and focusing magnets have been delivered and the magnetic fields measured recently. So the assumed values of the the multipole imperfections used so far in the machine model are now replaced by values based on fieldmeasurements.