SLAC, Menlo Park, California, USA
The Linac Coherent Light Source (LCLS) electron beam can damage YAG:Ce scintillation screens. After one year of use, the existing profile monitor has diminished fluorescence of the screen. The decrease in performance has resulted in distorted beam images which can com-promise the acquired data. Scheduling a YAG screen replacement is difficult, resulting in weeks of diminished performance. We have developed a unique profile moni-tor that incorporates multiple YAG screens (Ø40 mm, 50 um thick) and methods to reduce device downtime. This device uses unique geometry to direct coherent optical transition radiation (COTR) away from the optical path, which preserves the high resolution beam image. We are presenting the operational requirements, device design and installed device operational results.
