Author: Wehrle, U.
Paper Title Page
MOPC35 A Beam-Synchronous Gated Peak-Detector for the LHC Beam Observation System 147
 
  • T.E. Levens, T. Bohl, U. Wehrle
    CERN, Geneva, Switzerland
  
  Mea­sure­ments of the bunch peak am­pli­tude using the lon­gi­tu­di­nal wide­band wall-cur­rent mon­i­tor are a vital tool used in the Large Hadron Col­lider (LHC) beam ob­ser­va­tion sys­tem. These peak-de­tected mea­sure­ments can be used to di­ag­nose bunch shape os­cil­la­tions, for ex­am­ple co­her­ent quadru­pole os­cil­la­tions, that occur at in­jec­tion and dur­ing beam ma­nip­u­la­tions. Peak-de­tected Schot­tky di­ag­nos­tics can also be used to ob­tain the syn­chro­tron fre­quency dis­tri­b­u­tion and other pa­ra­me­ters from a bunched beam under sta­ble con­di­tions. For the LHC a beam-syn­chro­nous gated peak de­tec­tor has been de­vel­oped to allow in­di­vid­ual bunches to be mon­i­tored with­out the in­flu­ence of other bunches cir­cu­lat­ing in the ma­chine. The re­quire­ment for the ob­ser­va­tion of both low in­ten­sity pilot bunches and high in­ten­sity bunches for physics re­quires a de­tec­tor front-end with a high band­width and a large dy­namic range while the usage for Schot­tky mea­sure­ments re­quires low noise elec­tron­ics. This paper will pre­sent the de­sign of this de­tec­tor sys­tem as well as ini­tial re­sults ob­tained dur­ing the 2012-2013 LHC run.  
poster icon Poster MOPC35 [2.792 MB]  
 
WEPC12 Evaluation of Strip-line Pick-up System for the SPS Wideband Transverse Feedback System 690
 
  • G. Kotzian, W. Höfle, R.J. Steinhagen, D. Valuch, U. Wehrle
    CERN, Geneva, Switzerland
  
  The pro­posed SPS Wide­band Trans­verse Feed­back sys­tem re­quires a wide-band pick-up sys­tem to be able to de­tect in­tra-bunch mo­tion within the SPS pro­ton bunches, cap­tured and ac­cel­er­ated in a 200 MHz bucket. We pre­sent the elec­tro-mag­netic de­sign of trans­verse beam po­si­tion pick-up op­tions op­ti­mised for in­stal­la­tion in the SPS and eval­u­ate their per­for­mance reach with re­spect to di­rect time do­main sam­pling of the in­tra-bunch mo­tion. The analy­sis also dis­cusses the achieved sub­sys­tem re­sponses of the as­so­ci­ated ca­bling with new low dis­per­sion smooth wall ca­bles, wide-band gen­er­a­tion of in­ten­sity and po­si­tion sig­nals by means of 180 de­gree RF hy­brids as well as pas­sive tech­niques to elec­tron­i­cally sup­press the beam off­set sig­nal, needed to op­ti­mise the dy­namic range and po­si­tion res­o­lu­tion of the planned dig­i­tal in­tra-bunch feed­back sys­tem.