Speaker
Description
Beam dynamics studies have been performed to optimize the brightness of a superconducting radio-frequency (SRF) photoinjector for the CW option of the European XFEL. A superconducting L-band 1.6-cell cavity is considered as a high-brightness electron source capable of CW operation and meeting stringent beam quality requirements. Due to the limited achievable accelerating gradient in the SRF gun and the fixed layout with the gun separated from the solenoid, photocathode laser pulse shaping is used to mitigate space-charge-driven emittance growth. A 4D integral brightness metric, combining slice emittance and current profile, is used as the optimization objective. Multi-objective optimization using ASTRA is performed to minimize transverse emittance and maximize brightness for various temporal and transverse laser distributions. Optimized working points are tracked through start-to-end simulations up to the undulator entrance. A local gain-length model identifies relevant lasing electron bunch slices after three-stage compression, which are correlated with the 4D brightness of the longitudinal core at the injector exit, providing a figure of merit. Different laser pulse profiles are compared in terms of achievable performance.
| I have read and accept the Privacy Policy Statement | Yes |
|---|