Conceptual Design and Preliminary Verification of a Double-bunch Switchyard for SXFEL

The Shanghai soft X-ray free-electron laser (SXFEL) is the first X-ray free-electron laser (FEL) user facility in China. To improve the utilization efficiency of the linear accelerator, SXFEL plans to upgrade to double-bunch mode with a bunch time separation of 100 ns and a maximum repetition rate of 50 Hz. A new conceptual beam distribution system is designed to separate the double beam bunch-by-bunch. Conceptual design and prototype implementation of a double-bunch separation system was implemented. The beam distribution system consists of four in-vacuum kicker magnets and one Lambertson septum magnet. This paper presents the design considerations and preliminary verification of a beam bunch distribution system. Distributed magnets and excitation power supply are introduced in detail. The relevant simulation and experimental results of the magnets and pulsed power supply are introducedalso.