• J. Carwardine
  ANL, Argonne

An important milestone has been reached in in the 'FLASH 9mA experiment' at DESY, with successful operation of FLASH with long bunch trains and heavily beam-loaded cavities. Bunch trains up to 600μs were run at an average current of 9mA, extending to 800μs with a somewhat lower average current. The FLASH 9mA programme is led by DESY in collaboration with the ILC-GDE, and has the goal of demonstrating reliable operation and of characterizing limits of performance of the FLASH linac with 800us-long bunch trains, 9mA average current, and cavity gradients approaching quench. The programme provides important operations experience and technical input to the European XFEL and the International Linear Collider, and supports planned routine long bunch-train operation of FLASH for FEL users. This paper highlights the 9mA programme accomplishments to date, presents performance and operations data analysis, and gives an outlook for future studies.