Author: Levens, T.E.
Paper Title Page
WEPGF062 Processing High-Bandwidth Bunch-by-Bunch Observation Data from the RF and Transverse Damper Systems of the LHC 1
  • M. Ojeda Sandonís, P. Baudrenghien, A.C. Butterworth, J. Galindo, W. Höfle, T.E. Levens, J.C. Molendijk, D. Valuch
    CERN, Geneva, Switzerland
  • F. Vaga
    University of Pavia, Pavia, Italy
  The radiofrequency and transverse damper feedback systems of the Large Hadron Collider digitize beam phase and position measurements at the bunch repetition rate of 40 MHz. Embedded memory buffers allow a few milliseconds of full rate bunch-by-bunch data to be retrieved over the VME bus for diagnostic purposes, but experience during LHC Run I has shown that for beam studies much longer data records are desirable. A new "observation box" diagnostic system is being developed which parasitically captures data streamed directly out of the feedback hardware into a Linux server through an optical fiber link, and permits processing and buffering of full rate data for around one minute. The system will be connected to an LHC-wide trigger network for detection of beam instabilities, which allows efficient capture of signals from the onset of beam instability events. The data will be made available for analysis by client applications through interfaces which are exposed as standard equipment devices within CERN's controls framework. It is also foreseen to perform online Fourier analysis of transverse position data inside the observation box using GPUs with the aim of extracting betatron tune signals.  
poster icon Poster WEPGF062 [4.408 MB]  
THHB2O02 A Modular Approach to Acquisition Systems for Future CERN Beam Instrumentation Developments 1
  • A. Boccardi, M. Barros Marin, T.E. Levens, W. Viganò, C. Zamantzas
    CERN, Geneva, Switzerland
  This paper will present the new modular architecture adopted as a baseline by the CERN Beam Instrumentation Group for its future acquisition system developments. The main blocks of this architecture are: radiation tolerant digital front-ends; a latency deterministic multi gigabit optical link; a high pin count FMC carrier used as a VME-based back-end for data concentration and processing. Details will be given on the design criteria for each of these modules as well as examples of their use in systems currently being developed at CERN.  
slides icon Slides THHB2O02 [2.051 MB]