Author: Delsim-Hashemi, H.
Paper Title Page
TUZA02 sFLASH - Present Status and Commissioning Results 923
 
  • V. Miltchev, S. Ackermann, A. Azima, J. Bödewadt, F. Curbis, M. Drescher, E. Hass, Th. Maltezopoulos, M. Mittenzwey, J. Rönsch-Schulenburg, J. Roßbach, R. Tarkeshian
    Uni HH, Hamburg, Germany
  • H. Delsim-Hashemi, K. Honkavaara, T. Laarmann, H. Schlarb, S. Schreiber, M. Tischer
    DESY, Hamburg, Germany
  • R. Ischebeck
    PSI, Villigen, Switzerland
  • S. Khan
    DELTA, Dortmund, Germany
  
  The free-elec­tron laser in Ham­burg (FLASH) was pre­vi­ous­ly being op­er­at­ed in the self-am­pli­fied spon­ta­neous emis­sion (SASE) mode, pro­duc­ing pho­tons in the XUV wave­length range. Due to the start-up from noise the SASE-ra­di­a­tion con­sists of a num­ber of un­cor­re­lat­ed modes, which re­sults in a re­duced co­her­ence. One op­tion to si­mul­ta­ne­ous­ly im­prove both the co­her­ence and the syn­chro­ni­sa­tion be­tween the FEL-pulse and an ex­ter­nal laser is to op­er­ate FLASH as an am­pli­fi­er of a seed pro­duced using high har­mon­ics gen­er­a­tion (HHG). An ex­per­i­men­tal set-up - sFLASH, has been in­stalled to test this con­cept for the wave­lengths below 40 nm. The sFLASH in­stal­la­tion took place dur­ing the planed FLASH shut­down in the win­ter of 2009/2010. The tech­ni­cal com­mis­sion­ing, which began in the spring of 2010, has been fol­lowed by seed­ed-FEL com­mis­sion­ing, FEL-char­ac­ter­i­sa­tion and pilot ex­per­i­ments. In this con­tri­bu­tion the pre­sent sta­tus and the sFLASH com­mis­sion­ing re­sults will be dis­cussed.  
slides icon Slides TUZA02 [4.125 MB]  
 
TUPC081 Diagnostics of Femtosecond Low-charge Electron Bunches at REGAE 1192
 
  • S. Bayesteh
    Uni HH, Hamburg, Germany
  • H. Delsim-Hashemi
    DESY, Hamburg, Germany
  
  A new linac is con­struct­ed at DESY as the elec­tron source fo "Rel­a­tivis­tic Elec­tron Gun for Atom­ic Ex­plo­ration (REGAE)". REGAE is main­ly es­tab­lished for a Fem­tosec­ond elec­tron diffrac­tion ex­per­i­ment pre­sent­ing struc­tural in­for­ma­tion on atom­ic tran­si­tion states oc­cur­ring in the sub-hun­dred fem­tosec­ond time-scale. REGAE com­pris­es a pho­to-cath­ode gun fol­lowed by nor­mal con­duct­ing 1.5 cell RF cav­i­ty to pro­vide sub pi­co-Coulomb charge of 2 to 5 MeV en­er­gy with a co­her­ent length in the range of 30nm. In order to pro­duce and main­tain such high qual­i­ty elec­tron bunch­es, so­phis­ti­cat­ed sin­gle-shot di­ag­nos­tics is manda­to­ry to mon­i­tor the prop­er­ties. Di­ag­nos­tics in­clude emit­tance, en­er­gy, en­er­gy spread and bunch length mea­sure­ment. In this paper the con­cep­tu­al ideas and steps to­ward re­al­iza­tion of these di­ag­nos­tics are pre­sent­ed with a de­tailed focus on trans­verse di­ag­nos­tics. As for pho­ton source of transver­sal di­ag­nos­tics, scin­til­la­tors are stud­ied. Sim­u­la­tion re­sults show which ma­te­ri­al suits the best for REGAE pa­ram­e­ters. Lay­out of a home-made in­ten­si­fied cam­era is pre­sent­ed. The method dis­cussed in this paper would also be ad­van­ta­geous for low-charge Free Elec­tron Lasers.