Author: Serrano, C.
Paper Title Page
WEPPP073 Dynamic Feedback Model for High Repetition Rate Linac-driven FELs 2879
  • J.M. Byrd, L.R. Doolittle, P. Emma, G. Huang, A. Ratti, C. Serrano
    LBNL, Berkeley, California, USA
  Funding: Work supported by the Director, Office of Science, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
One of the concepts for the next generation of linac-driven FELs is a cw superconducting linac driving an electron beam with MHz repetition rates. One of the challenges for next generation FELs is improve the shot-to-shot stability of the energy, charge, peak current, and timing jitter of the electron beam. The use of a cw RF system with MHz beam repetition rates presents an opportunity to use broadband feedback to stabilize the beam parameters. To understand the performance of such a feedback system, we are are developing a dynamic feedback model of the machine with a focus on the longitudinal beam properties. The model is being developed as an extension of the LITrack code and will include the dynamics of the beam-cavity interaction, RF feedback, beam-based feedback, and multibunch effects. In this paper, we will present the status of this model along with results.
THPPC087 Software Firmware Infrastructure for LLRF4 Based System 3485
  • G. Huang, L.R. Doolittle, C. Serrano
    LBNL, Berkeley, California, USA
  LLRF4 is a successfully designed FPGA based low noise llrf signal process board. The board has been used in server accelerator as low level RF control and timing system. The complexity of maintain and support different version of software and firmware increase as the application increase. This paper describe our attempt to abstract the software and firmware layer. In the software side, the infrastructure support original rgui like GUI and also provide EPICS IOC driver. From the firmware side, the infrastructure separate board hardware dependent driver, the common algorithm implementation and project specific DSP, it also reserved the capability to expend to UDP based communication and next generation llrf board.