Introducing Fast Orbit Feedback at BESSY
I.Mueller, J.Rahn, R.Goergen, R.Lange, R.Müller* (Helmholtz-Zentrum Berlin für Materialien und Energie GmbH Elektronen-Speicherring BESSY II)
Over the more than ten years of BESSY II operation the strategy of eliminating beam perturbation sources and precisely compensating for slow orbit drifts successfully provided the micron and sub-microradian beam stability required by the experiments. In view of increased processing bandwidth at the experiments and the demand for rapid compensation of noise spikes and new, yet unknown excitations a fast orbit feedback aiming at noise suppression in the 1Hz-50Hz range will be installed. Phase I of the implementation foresees fast setpoint transmission plus replacement of all corrector power supplies and aims at higher correction speed. Phase II intends to replace today's multiplexed analog beam position monitors by parallel processing fast digital units to increase correction precision in combination with top-up operation.