Author: Vinzenz, W.
Paper Title Page
PO04 The Darmstadt Multi-Frequency Digital Low Level RF System in Pulsed Application 58
  • R. Eichhorn, U. Bonnes, C. Burandt, M. Konrad, P.N. Nonn
    TU Darmstadt, Darmstadt, Germany
  • G. Schreiber, W. Vinzenz
    GSI, Darmstadt, Germany
  Funding: Work supported by DFG through CRC 634 and by the BMBF under 06 DA 9024 I
Triggered by the need to control the superconducting cavities of the S-DALINAC, the development of a digital low level RF control system was started several years ago. The chosen design proved to be very flexible since other frequencies than the original 3 GHz may be adapted easily: The system converts the RF signal coming from the cavity (e. g. 3 GHz) down to the base band using a hardware I/Q demodulator. The base band signals are digitized by ADCs and fed into a FPGA where the control algorithm is implemented. The resulting signals are I/Q modulated before they are sent back to the cavity. Meanwhile, this system has been successfully operated on 3 GHz, 6 GHz and 325 MHz cavities, on normal and superconducting cavities as well as in cw or pulsed mode. This contribution will focus on the 325 MHz version built to control a pulsed prototype test stand for the p-LINAC at FAIR and possible extensions to even lower frequencies. We will present the architecture of the RF control system as well as results obtained during operation.
WEC05 Design Studies for a New Heavy Ion Injector Linac for FAIR 191
  • B. Schlitt, W.A. Barth, G. Clemente, W. Vinzenz
    GSI, Darmstadt, Germany
  As the GSI UNILAC started operation in 1975, it will be more than 40 years old when the commissioning of the future Facility for Antiproton and Ion Research (FAIR) at GSI will start. To assure reliable operation for FAIR and to provide beams for a variety of experiments, three separate linacs are proposed: 1.) A new superconducting cw heavy-ion linac behind the upgraded high charge state injector HLI shall provide ion beams with high duty cycle and adjustable energy in the MeV/u region for the super-heavy element program as well as for further UNILAC experiments. 2.) A dedicated 70 MeV proton linac will serve as injector for the FAIR pbar physics program. 3.) To deliver high-intensity heavy-ion beams for FAIR, the existing post-stripper linac should be replaced by a new high energy linac with short beam pulses, low pulse repetition rate, and fixed end energy. Conceptual design studies for the latter machine using 108 MHz IH-type drift tube structures will be presented, including a proposal to increase the ion charge states for synchrotron injection as well as a linac beam energy upgrade using 325 MHz CH structures.  
slides icon Slides WEC05 [6.013 MB]