Author: Grünert, J.
Paper Title Page
MOP009
 K-Monochromator for Undulator Commissioning at the European XFEL  
 
  • W. Freund, J. Grünert, A. Koch
    XFEL. EU, Hamburg, Germany
  
  Pho­ton beam based com­mis­sion­ing of the Eu­ro­pean XFEL un­du­la­tors re­quires vari­able 4-bounce mono­chro­ma­tor sys­tems equipped with Si(111) chan­nel-cut crys­tals. With two dif­fer­ent meth­ods we will mea­sure the K-pa­ra­me­ters of each seg­ment of the SASE un­du­la­tors (e.g. SASE1 has 35 seg­ments) which has to be tuned to a pre­ci­sion of bet­ter than 2·10-4 in order to achieve las­ing con­di­tions. Pre­cise mag­netic K-tun­ing of the un­du­la­tor seg­ments is per­formed in the mag­netic lab, but this mea­sure­ment is not avail­able after un­du­la­tor in­stal­la­tion in the tun­nel. We will de­scribe the K-mono­chro­ma­tor sys­tem for the first un­du­la­tor beam­line SASE1, which is planned to be in­stalled this year. The sys­tem con­sists of three main com­po­nents, a cham­ber with fil­ter foils, a mono­chro­ma­tor cham­ber with two go­niome­ters car­ry­ing the chan­nel-cut crys­tals, and a de­tec­tion cham­ber with an im­ager and a pho­to­di­ode. For the imag­ing sys­tem we will use a highly sen­si­tive sCMOS cam­era with tan­dem lens op­tics for high nu­mer­i­cal aper­ture and up to three dif­fer­ent scin­til­la­tion screens.  
 
MOP012 Implementation Phase of the European XFEL Photon Diagnostics 41
 
  • J. Grünert, J. Buck, F. Dietrich, W. Freund, A. Koch, M. Planas
    XFEL. EU, Hamburg, Germany
  
  The Eu­ro­pean XFEL fa­cil­ity with 3 un­du­la­tors and ini­tially 6 ex­per­i­men­tal end-sta­tions re­quires an ex­ten­sive set of pho­ton beam di­ag­nos­tics for com­mis­sion­ing and user op­er­a­tion, ca­pa­ble of han­dling the ex­treme bril­liance and its in­her­ent dam­age po­ten­tial, and the high intra bunch train rep­e­ti­tion rate of 4.5MHz, po­ten­tially caus­ing ad­di­tional dam­age by high heat loads and mak­ing shot-to-shot di­ag­nos­tics very de­mand­ing [1]. After ex­ten­sive de­sign [2-4] and pro­to­type stud­ies, in 2014 the in­stal­la­tion of the pho­ton beam de­vices starts with the equip­ment in the first pho­ton tun­nel XTD2 which is where the SASE1 hard X-ray un­du­la­tor is lo­cated. This con­tri­bu­tion re­ports on the de­vice con­struc­tion progress by fo­cus­ing on the XTD2 tun­nel de­vices and their im­ple­men­ta­tion into the tun­nel en­vi­ron­ment. [1] J.​Grünert, Frame­work for X-Ray Pho­ton Di­ag­nos­tics at the Eu­ro­pean XFEL, TR-2012-003, 04/2012 [2] J.​Buck, On­line Pho­toe­mis­sion Time-of-Flight Spec­trom­e­ter for X-ray Pho­ton Di­ag­nos­tics, TR-2012-002, 06/2012 [3] C.​Ozkan, Con­cep­tual de­sign re­port for Imag­ing Sta­tions at the Eu­ro­pean XFEL, TR-2012-004, 02/2012 [4] W.​Freund, The Eu­ro­pean XFEL Un­du­la­tor Com­mis­sion­ing Spec­trom­e­ter, XFEL. EU 05/2011  
 
MOP013
 Design of Invasive X-ray Beam Diagnostic Devices for the European XFEL Employing Scintillators for Imaging  
 
  • A. Koch, W. Freund, J. Grünert
    XFEL. EU, Hamburg, Germany
  
  The Eu­ro­pean XFEL fa­cil­ity re­quires di­ag­nos­tics of its x-ray pho­ton beam. Imag­ing sta­tions will be em­ployed for in­va­sive char­ac­ter­i­sa­tions of beam prop­er­ties like po­si­tion, pro­file, and point­ing. In com­bi­na­tion with mono­chro­ma­tors or dis­per­sive de­vices, im­agers can also de­liver spec­tral in­for­ma­tion. This con­tri­bu­tion will de­scribe the de­sign of dif­fer­ent imag­ing sta­tions, their ex­pected per­for­mance and first char­ac­ter­i­sa­tions, es­pe­cially in terms of sig­nal-to-noise prop­er­ties, spa­tial res­o­lu­tion and ra­di­a­tion hard­ness. The chal­lenge in the de­sign is to deal with a wide range of beam prop­er­ties: pho­ton en­er­gies from 0.26 – 36 keV, beam sizes from sev­eral 100 um to mm, pulse du­ra­tions of 10 fs and pulse en­er­gies up to 10 mJ which may de­stroy ma­te­ri­als by sin­gle pulses. The main com­po­nents of these imag­ing sta­tions are: scin­til­la­tors for con­ver­sion of x-rays to vis­i­ble light, mir­rors - both in vac­uum - spe­cialised op­tics and CCD / CMOS cam­eras for image record­ing.  
 
MOP014 X-ray Photon Temporal Diagnostics for the European XFEL 45
 
  • J. Liu, J. Buck, F. Dietrich, W. Freund, J. Grünert, M. Meyer
    XFEL. EU, Hamburg, Germany
  
  Eu­ro­pean XFEL (XFEL. EU) that will com­mis­sion­ing in 2016 shows great fea­tures on its ex­tremely high num­ber of light bul­lets (27000 p/s) and ex­tremely high av­er­age bril­liance. The FEL pulses in XFEL. EU are pro­duced in a 10 Hz bunch trains that con­tains 2700 sub-pulses within the 600 μs time in­ter­vals, cor­re­spond­ing to a 220 ns sub-pulse sep­a­ra­tion and 4.5 MHz rep­e­ti­tion rate. Char­ac­ter­iz­ing the tem­po­ral prop­er­ties of the high rep­e­ti­tion rate FEL pulses that im­plic­itly dif­fer­ent from shot to shot is im­por­tant for “pump and probe” ex­per­i­ments and data in­ter­pre­ta­tion. Here we re­port the con­cept and re­cent progress about tem­po­ral di­ag­nos­tic for XFEL. EU. THz streak­ing tech­nique and spec­tral en­cod­ing will be im­ple­mented con­sid­er­ing the high rep­e­ti­tion rate and high bril­liance of XFEL. EU. Laser based THz gen­er­a­tion, op­ti­miza­tion and nu­mer­i­cal sim­u­la­tion for streak­ing FEL elec­trons with dif­fer­ent pho­ton en­er­gies will be pre­sented. High rep­e­ti­tion rate di­ag­nos­tic re­quire­ments and so­lu­tions will also be dis­cussed.