STATUS OF THE SHORT-PULSE X-RAY ( SPX ) PROJECT AT THE ADVANCED PHOTON SOURCE ( APS )

The Advanced Photon Source Upgrade (APS-U) at Argonne includes implementation of Zholents’ rf deflection concept [1] for production of short x-ray pulses. This is a joint project between Argonne National Laboratory, Thomas Jefferson National Laboratory (JLab), and Lawrence Berkeley National Laboratory. This paper describes performance characteristics of the proposed sources and technical issues related to its realization. Ensuring stable APS storage ring operation requires reducing the quality factors of both lower-orderand higher-order-modes of the single-cell superconducting rf deflecting cavities that can achieve operating deflecting fields while providing needed damping of all these modes. The project team is currently prototyping and testing several promising designs for single-cell cavities with the goal of down selecting a design in the near future. Here we describe the approach undertaken and report the preliminary results.