High Charge per Bunch RF Gun Photocathode

A definitive experimental study of photoemissive materials and cathode design and fabrication for RF electron injectors is proposed that will result in a recommended cathode approach for next step Navy FEL devices at the end of the program. The University of Maryland (UMD) and Brookhaven National Laboratory (BNL) are collaborating with Advanced Energy Systems (AES) on this project. As an FFRDC, BNL will not receive any SBIR funding but has agreed to provide access to its facilities and equipment thereby providing great leverage to the program. UMD will continue to develop their proprietary dispenser cathodes. BNL will continue to develop high-quantum-efficiency multi-alkali cathode materials and the novel exciting diamond amplifier cathode concept. AES will fabricate a cathode preparation chamber and transport system, compatible with UMD and BNL cathodes, for integration with a high-power superconducting RF gun. Optimization of cathode preparation will be followed by high-average current tests of specific UMD and BNL cathodes. Target performance is a continuous average cathode current approaching 0.5 Ampere.