Author: Federmann, S.
Paper Title Page
TUPF27 An Ultra Low-Noise AC Beam Transformer and Digital Signal Processing System for CERN’s ELENA Ring 571
 
  • M.E. Angoletta, C. Carli, F. Caspers, S. Federmann, J.C. Molendijk, F. Pedersen, J. Sanchez-Quesada
    CERN, Geneva, Switzerland
  
  CERN’s Extra Low EN­ergy An­tipro­ton (ELENA) Ring is a new syn­chro­tron that will be com­mis­sioned in 2016 to fur­ther de­cel­er­ate the an­tipro­tons com­ing from CERN’s An­tipro­ton De­cel­er­a­tor. Es­sen­tial lon­gi­tu­di­nal di­ag­nos­tics re­quired for com­mis­sion­ing and op­er­a­tion in­clude the in­ten­sity mea­sure­ment for bunched and de­bunched beams and the mea­sure­ment of Dp/p for de­bunched beams to as­sess the elec­tron cool­ing per­for­mance. The beam phase in­for­ma­tion is also needed by the low-level RF sys­tem. The base­line sys­tem for pro­vid­ing the re­quired beam pa­ra­me­ters and sig­nals is based upon two ul­tra-low-noise AC beam trans­form­ers and as­so­ci­ated dig­i­tal sig­nal pro­cess­ing. The AC beam trans­form­ers cover dif­fer­ent fre­quency re­gions and are an adap­ta­tion to the ELENA lay­out of those used in the AD. Two AC beam trans­form­ers will also be in­stalled in the ex­trac­tion lines to pro­vide beam in­ten­sity and bunch shape mea­sure­ments. The dig­i­tal sig­nal pro­cess­ing will be car­ried out with the lead­ing-edge hard­ware fam­ily used for ELENA’s low-level RF sys­tem. The paper pro­vides an overview of the beam trans­former and head am­pli­fier, as well as of the as­so­ci­ated dig­i­tal sig­nal pro­cess­ing.  
 
WEPF28 Longitudinal Beam Diagnostic from a Distributed Electrostatic Pick-Up in CERN’s ELENA Ring 883
 
  • M.E. Angoletta, F. Caspers, S. Federmann, J.C. Molendijk, P.J. Pascal Jean, F. Pedersen, J. Sanchez-Quesada, L. Søby, M.A. Timmins
    CERN, Geneva, Switzerland
  
  The CERN Extra Low EN­ergy An­tipro­ton (ELENA) Ring is a new syn­chro­tron that will be com­mis­sioned in 2016 to fur­ther de­cel­er­ate the an­tipro­tons com­ing from CERN’s An­tipro­ton De­cel­er­a­tor (AD). Re­quired lon­gi­tu­di­nal di­ag­nos­tics in­clude the in­ten­sity mea­sure­ment for bunched and de­bunched beam and the mea­sure­ment of Dp/p for a de­bunched beam to as­sess the elec­tron cool­ing per­for­mance. A novel method for the cal­cu­la­tion of these pa­ra­me­ters is pro­posed for ELENA, where sig­nals from the twenty elec­tro­sta­tic pick-ups (PU) used for orbit mea­sure­ments will be com­bined to im­prove the sig­nal-to-noise ratio. This re­quires that the sig­nals be dig­i­tally down-con­verted, ro­tated and dig­i­tally summed so that the many elec­tro­sta­tic PUs will func­tion as a sin­gle, dis­trib­uted PU from to the pro­cess­ing sys­tem view­point. This method in­cludes some chal­lenges and will not be used as the base­line lon­gi­tu­di­nal di­ag­nos­tics for the ini­tial ELENA op­er­a­tion. This paper gives an overview of the hard­ware and dig­i­tal sig­nal pro­cess­ing in­volved, as well as of the chal­lenges that will have to be faced.