High QE photocathodes performance during operation at FLASH / PITZ photoinjectors

Since 1998, the DESY photoinjectors at FLASH and PITZ routinely use high quantum efficiency (QE) photocathodes produced at LASA (INFN-Milano). To further understand the photocathode behavior during beam operation, photocathode QE measurements have been performed at different operating conditions in both photoinjectors. The analysis of these measurements will be used to improve the photocathode preparation procedures and deepen our understanding of the photocathode properties. An important goal is to further increase their lifetime and to preserve a high beam quality during the operation in the RF gun of the photoinjector.