Author: Ackermann, S.
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]  
 
TUPD11 Optimization of HHG Seeding at Flash II 249
 
  • S. Ackermann, B. Faatz
    DESY, Hamburg, Germany
  • V. Miltchev, J. Roßbach
    Uni HH, Hamburg, Germany
 
  FLASH* delivers coherent FEL radiation suitable for a variety of scientific purposes. In order to provide more beam time to the photon experiments, the FLASH II project, consisting of a second undulator branch and a new experimental Hall driven by the same superconducting modules as FLASH today has been started in 2008. While in the present undulator the kinetic energy of the electrons has to be changed in order to change the wavelength, the new beamline will benefit from variable gap undulators which will allow to have largely independent radiation wavelength; in the range of 10 to 40 nm an HHG seeding option is foreseen which will improve radiation quality for users beyond SASE. For experiments it is important to have the source point of the FEL radiation at the same position, close to the end of the undulator. However, one would like to keep the HHG focus at a fixed longitudinal position, such that wavelength changes will not require adjustments of the HHG focus. In this contribution, we will present the optimization of these conflicting requirements by opening undulator gaps at wavelength dependent positions, keeping both the seeding point and the source point for users fixed.
* The Free-Electron Laser in Hamburg
 
 
TUPD32 Simultaneous Operation of a Multi Beamline FEL Facility 301
 
  • B. Faatz, S. Ackermann, V. Ayvazyan, W. Decking, C. Grün, K. Klose, F. Obier, S. Pfeiffer, M. Scholz, J. Wortmann
    DESY, Hamburg, Germany
  • E. Hass
    Uni HH, Hamburg, Germany
 
  The FLASH II project will add an undulator beamline and a new experimental Hall to the existing FLASH Facility. In addition to improving the radiation properties of the FEL by using seeding, one of the main goals is to double the beamtime of the facility for users. At the moment, we deliver photon pulses in 10 Hz bursts with up to 800 bunches within each RF pulse. In order not to limit parameter ranges, we will have to give those same tuning possibilities within an RF pulse for each of the users independently. For this purpose, several tests have been performed to determine the limits of the difference in beam parameters which can be delivered. We will show to what extend we can switch fast between two beamlines, how we can change photon pulse length by allowing different charges, have different energy in the two beamlines simultaneously to allow for wavelength scans for the fixed-gap undulator presently built in FLASH, while not interfering with user operation of the new beamline.  
 
WEPD07 Status of the FLASH II Project 381
 
  • K. Honkavaara, S. Ackermann, V. Ayvazyan, N. Baboi, V. Balandin, W. Decking, S. Düsterer, H.-J. Eckoldt, B. Faatz, M. Felber, J. Feldhaus, N. Golubeva, M. Körfer, M. Kuhlmann, T. Laarmann, A. Leuschner, L. Lilje, T. Limberg, N. Mildner, D. Nölle, F. Obier, A. Petrov, E. Plönjes, K. Rehlich, H. Remde, H. Schlarb, B. Schmidt, M. Schmitz, M. Scholz, S. Schreiber, H. Schulte-Schrepping, J. Spengler, M. Staack, N. Stojanovic, K.I. Tiedtke, M. Tischer, R. Treusch, M. Vogt, H.C. Weddig, T. Wohlenberg
    DESY, Hamburg, Germany
  • M. Drescher, A. Hage, V. Miltchev, R. Riedel, J. Rönsch-Schulenburg, J. Roßbach, M. Schulz, A. Willner
    Uni HH, Hamburg, Germany
  • F. Tavella
    HIJ, Jena, Germany
 
  The extension of the FLASH facility at DESY (Hamburg, Germany) - FLASH II Project - is under way. The extension includes a second undulator line with variable gap undulators to allow a more flexible operation, and a new experimental hall for photon experiments. The present FLASH linac will drive the both undulator beamlines. Civil construction of the new buildings has been started in autumn 2011 continuing in several steps until early 2013. The design of the new beamline including the extraction from the FLASH linac and the undulator is mostly finished, and the manufacturing of the components is under way. The mounting of the beamline will start in autumn 2012, and the commissioning with beam is scheduled for second half of 2013. We report here the design of the different phases of the project including the time schedule up to the first user operation.