Author: Müller, G.J.
Paper Title Page
MOMMU003 Aperture Meter for the Large Hadron Collider 70
 
  • G.J. Müller, K. Fuchsberger, S. Redaelli
    CERN, Geneva, Switzerland
 
  The control of the high intensity beams of the CERN Large Hadron Collider (LHC) is particular challenging and requires a good modeling of the machine and monitoring of various machine parameters. During operation it is crucial to ensure a minimal distance between the beam edge and the aperture of sensitive equipment, e.g. the superconducting magnets, which in all cases must be in the shadow of the collimators that protect the machine. Possible dangerous situations must be detected as soon as possible. In order to provide the operator with information about the current machine bottlenecks an aperture meter application was developed based on the LHC online modeling toolchain. The calculation of available free aperture takes into account the best available optics and aperture model as well as the relevant beam measurements. This paper describes the design and integration of this application into the control environment and presents results of the usage in daily operation and from validation measurements.  
slides icon Slides MOMMU003 [0.565 MB]  
poster icon Poster MOMMU003 [0.694 MB]  
 
MOPKN002 LHC Supertable 86
 
  • M. Pereira, M. Lamont, G.J. Müller, D.D. Teixeira
    CERN, Geneva, Switzerland
  • T.E. Lahey
    SLAC, Menlo Park, California, USA
  • E.S.M. McCrory
    Fermilab, Batavia, USA
 
  LHC operations generate enormous amounts of data. These data are being stored in many different databases. Hence, it is difficult for operators, physicists, engineers and management to have a clear view on the overall accelerator performance. Until recently the logging database, through its desktop interface TIMBER, was the only way of retrieving information on a fill-by-fill basis. The LHC Supertable has been developed to provide a summary of key LHC performance parameters in a clear, consistent and comprehensive format. The columns in this table represent main parameters that describe the collider's operation such as luminosity, beam intensity, emittance, etc. The data is organized in a tabular fill-by-fill manner with different levels of detail. A particular emphasis was placed on data sharing by making data available in various open formats. Typically the contents are calculated for periods of time that map to the accelerator's states or beam modes such as Injection, Stable Beams, etc. Data retrieval and calculation is triggered automatically after the end of each fill. The LHC Supertable project currently publishes 80 columns of data on around 100 fills.  
 
MOPMN018 Toolchain for Online Modeling of the LHC 277
 
  • G.J. Müller, X. Buffat, K. Fuchsberger, M. Giovannozzi, S. Redaelli, F. Schmidt
    CERN, Geneva, Switzerland
 
  The control of high intensity beams in a high energy, superconducting machine with complex optics like the CERN Large Hadron Collider (LHC) is challenging not only from the design aspect but also for operation. To support the LHC beam commissioning, operation and luminosity production, efforts were recently devoted towards the design and implementation of a software infrastructure aimed to use the computing power of the beam dynamics code MADX-X in the framework of the Java-based LHC control and measurement environment. Alongside interfacing to measurement data as well as to settings of the control system, the best knowledge of machine aperture and optic models is provided. In this paper, we present the status of the toolchain and illustrate how it has been used during commissioning and operation of the LHC. Possible future implementations are also discussed.  
poster icon Poster MOPMN018 [0.562 MB]  
 
FRBHAULT01 Feed-forward in the LHC 1302
 
  • M. Pereira, X. Buffat, K. Fuchsberger, M. Lamont, G.J. Müller, S. Redaelli, R.J. Steinhagen, J. Wenninger
    CERN, Geneva, Switzerland
 
  The LHC operational cycle is comprised of several phases such as the ramp, the squeeze and stable beams. During the ramp and squeeze in particular, it has been observed that the behaviour of key LHC beam parameters such as tune, orbit and chromaticity are highly reproducible from fill to fill. To reduced the reliance on the crucial feedback systems, it was decided to perform fill-to-fill feed-forward corrections. The LHC feed-forward application was developed to ease the introduction of corrections to the operational settings. It retrieves the feedback system's corrections from the logging database and applies appropriate corrections to the ramp and squeeze settings. The LHC Feed-Forward software has been used during LHC commissioning and tune and orbit corrections during ramp have been successfully applied. As a result, the required real-time corrections for the above parameters have been reduced to a minimum.  
slides icon Slides FRBHAULT01 [0.961 MB]