High Resolution Stabilisation of Vertical Photon Beam Position in SRS Beam Lines

Following the installation and commissioning of a new high resolution steering magnet control system and high precision photon monitors on the SRS beam lines, automatic feedback control of vertical position is now in routine operational use. Orbit correction bumps can be set to micron level accuracy and this matches the resolution of the tungsten vane photon monitoring system. This paper describes the application of the new systems, particularly on the 5 Tesla Wiggler beam line, and demonstrates the nature of the improvements achieved.