Author: Azima, A.
Paper Title Page
TUOAI01 First Direct Seeding at 38nm 197
 
  • C. Lechner, A. Azima, J. Bödewadt, M. Drescher, E. Hass, U. Hipp, Th. Maltezopoulos, V. Miltchev, M. Rehders, J. Rönsch-Schulenburg, J. Roßbach, R. Tarkeshian, M. Wieland
    Uni HH, Hamburg, Germany
  • S. Ackermann, S. Bajt, H. Dachraoui, H. Delsim-Hashemi, S. Düsterer, B. Faatz, K. Honkavaara, T. Laarmann, M. Mittenzwey, H. Schlarb, S. Schreiber, L. Schroedter, M. Tischer
    DESY, Hamburg, Germany
  • F. Curbis
    MAX-lab, Lund, Sweden
  • R. Ischebeck
    PSI, Villigen PSI, Switzerland
  • S. Khan
    DELTA, Dortmund, Germany
  • V. Wacker
    University of Hamburg, Hamburg, Germany
 
  Funding: The project is supported by the Federal Ministry of Education and Research of Germany under contract No. 05 K10GU1 and by the German Research Foundation programme graduate school 1355.
The sFLASH project at DESY is an experiment to study direct seeding using a source based on the high-harmonic generation (HHG) process. In contrast to SASE, a seeded FEL exhibits greatly improved longitudinal coherence and higher shot-to-shot stability (both spectral and energetic). In addition, the output of the seeded FEL is intrinsically synchronized to the HHG drive laser, thus enabling pump-probe experiments with a resolution of the order of 10 fs. The installation and successful commissioning of the sFLASH components in 2010/2011 has been followed by a planned upgrade in autumn 2011. As a result of these improvements, in spring 2012 direct HHG seeding at 38 nm has been successfully demonstrated. In this contribution, we describe the experimental layout and announce the first seeding at 38 nm.
 
slides icon Slides TUOAI01 [11.553 MB]  
 
TUPD13 Progress Towards HGHG and EEHG at FLASH 257
 
  • K.E. Hacker, C. Behrens, H. Schlarb
    DESY, Hamburg, Germany
  • G. Angelova Hamberg, V.G. Ziemann
    Uppsala University, Uppsala, Sweden
  • A. Azima, J. Bödewadt
    Uni HH, Hamburg, Germany
  • S. Khan, R. Molo
    DELTA, Dortmund, Germany
  • P. Salén, P. van der Meulen
    FYSIKUM, AlbaNova, Stockholm University, Stockholm, Sweden
 
  Funding: BMBF 05K10PE1 and DESY
New infrastructure was built at FLASH to enable 30-100 fs long, milliJoule pulses of 270 nm light to seed the electron beam with HGHG and EEHG techniques, targeting wavelengths in the range from 10 nm to 40 nm. HGHG, or High Gain Harmonic Generation, and EEHG, or Echo-Enabled Harmonic Generation, utilize an external laser together with chicanes and undulators in order to generate a bunched beam which will radiate in a subsequent undulator. In the case of HGHG, the beam is bunched at the seed laser wavelength, radiating harmonics thereof in the radiator. In the case of EEHG, the beam is bunched at a harmonic of the seed wavelength, radiating that same harmonic in the radiator. The properties of the setup, commissioning difficulties and the inital attempts at HGHG seeding at 38.5 nm will be described.