Author: Keil, B.
Paper Title Page
MOBL1 Instrumentation and Results from the SwissFEL Injector Test Facility 12
 
  • R. Ischebeck, V.R. Arsov, S. Bettoni, B. Beutner, M.M. Dehler, A. Falone, F. Frei, I. Gorgisyan, Ye. Ivanisenko, P.N. Juranic, B. Keil, F. Löhl, G.L. Orlandi, M. Pedrozzi, P. Pollet, E. Prat, T. Schietinger, V. Schlott, B. Smit
    PSI, Villigen PSI, Switzerland
  • P. Peier
    DESY, Hamburg, Germany
  
  The Swiss­FEL In­jec­tor Test Fa­cil­ity (SITF) has been equipped with nu­mer­ous pro­to­type di­ag­nos­tics (BPMs, screen mon­i­tors, wire scan­ners, op­ti­cal syn­chro­tron ra­di­a­tion mon­i­tor, com­pres­sion (THz) mon­i­tor, bunch ar­rival time mon­i­tor, EO spec­tral de­cod­ing mon­i­tor, charge and loss mon­i­tor) specif­i­cally de­signed for the low charge Swiss­FEL op­er­a­tion modes. The de­sign of the di­ag­nos­tics sys­tems and re­cent mea­sure­ment re­sults will be pre­sented.  
slides icon Slides MOBL1 [35.165 MB]  
 
TUPC25 Design of the SwissFEL BPM System 427
 
  • B. Keil, R. Baldinger, R. Ditter, W. Koprek, R. Kramert, F. Marcellini, G. Marinkovic, M. Roggli, M. Rohrer, M. Stadler, D.M. Treyer
    PSI, Villigen PSI, Switzerland
  
  Swiss­FEL is a Free Elec­tron Laser (FEL) fa­cil­ity being con­structed at PSI, based on a 5.8GeV nor­mally con­duct­ing main linac. A pho­to­cath­ode gun will gen­er­ate two bunches with 28ns spac­ing at 100Hz rep­e­ti­tion rate, with a nom­i­nal charge range of 10-200pC. A fast beam dis­tri­b­u­tion kicker will allow to dis­trib­ute one bunch to a soft X-ray un­du­la­tor line and the other bunch to a 0.1nm hard X-ray un­du­la­tor line. The Swiss­FEL elec­tron beam po­si­tion mon­i­tor (BPM) sys­tem will em­ploy three dif­fer­ent types of dual-res­onator cav­ity BPMs, since the ac­cel­er­a­tor has three dif­fer­ent beam pipe aper­tures. In the in­jec­tor and main linac (38mm and 16mm aper­ture), 3.3GHz cav­ity BPMs will be used, where a low Q of ~40 was cho­sen to min­i­mize crosstalk of the two bunches*. In the un­du­la­tors that just have sin­gle bunches and 8mm BPM aper­ture, a higher Q will be cho­sen. This paper re­ports on the de­vel­op­ment sta­tus of the Swiss­FEL BPM sys­tem. Syn­er­gies as well as dif­fer­ences to the E-XFEL BPM sys­tem** will also be high­lighted.
* F. Marcellini et al., "Design of Cavity BPM Pickups For SwissFEL", Proc. IBIC'12, Tsukuba, Japan, 2012.
** B. Keil et al., "The European XFEL BPM System", Proc. IPAC'10, Kyoto, Japan, 2010. 		 
poster icon Poster TUPC25 [1.074 MB]  
 
WEPC21 Design and Beam Test Results of Button BPMs for the European XFEL 723
 
  • D.M. Treyer, R. Baldinger, R. Ditter, B. Keil, W. Koprek, G. Marinkovic, M. Roggli
    PSI, Villigen PSI, Switzerland
  • D. Lipka, D. Nölle, S. Vilcins
    DESY, Hamburg, Germany
  
  Funding: Swiss State Secretariat for Education, Research and Innovation
The Eu­ro­pean X-ray Free Elec­tron Laser (E-XFEL) will use a total ~300 but­ton BPMs along the whole ac­cel­er­a­tor, as well as 160 cav­ity BPMs. The pick­ups for the but­ton BPMs have been de­signed by DESY, whereas the elec­tron­ics has been de­vel­oped by PSI. This paper gives an overview of the but­ton BPM sys­tem, with focus on the RF front end elec­tron­ics, sig­nal pro­cess­ing, and over­all sys­tem per­for­mance. Mea­sure­ment re­sults achieved with pro­to­types in­stalled at FLASH/DESY and at the Swiss­FEL In­jec­tor Test Fa­cil­ity (SITF) are pre­sented. The po­si­tion noise ob­tained with but­ton pick­ups in a 40.5 mm aper­ture beam pipe is as low as ~11 um at 20 pC bunch charge. 		 
poster icon Poster WEPC21 [1.595 MB]  
 
FRWMJ6
 Cavity BPM Activities at PSI  
 
  • B. Keil
    PSI, Villigen PSI, Switzerland
  
  Boris re­ported on cav­ity BPM ac­tiv­i­ties at PSI for var­i­ous pro­jects: Read-out elec­tron­ics for FLASH and XFEL, and an en­tire cav­ity BPM sys­tem for the Swiss­FEL. He com­pared the re­quire­ments of the BPMs in the dif­fer­ent areas of the ac­cel­er­a­tor, and pre­sented the an­tic­i­pated cav­ity BPM pickup and read-out so­lu­tions. Boris also showed the re­sults from the pro­to­type R&D at the Swiss­FEL In­jec­tor Test Fa­cil­ity, which in­cluded a dif­fer­ent con­cept, with a di­rect ana­log down­con­ver­sion to base­band, and a novel tech­nique of ADC clock phase feed­back to align ADC sam­ples to the peak on the sig­nal wave­form. The res­o­lu­tion of the dif­fer­ent pro­to­type BPMs, achieved dur­ing the beam tests, range within a few 100nm, far bet­ter than the re­quire­ment. A very in­ter­est­ing side as­pect men­tioned by Boris, was the in­ves­ti­ga­tion of UHV coax­ial feedthroughs for high fre­quen­cies. As every­one ob­serves, the known niche com­pa­nies in­creased their prices to the ex­treme, forc­ing the com­mu­nity to search for al­ter­na­tives. Boris found a Swiss man­u­fac­turer, who now pro­vides cus­tom feedthroughs with ac­cept­able UHV and RF prop­er­ties (re­turn loss >30dB@​3GHz) at mod­er­ated to low costs. Very in­ter­est­ing!  
slides icon Slides FRWMJ6 [2.044 MB]