Author: Stephan, F.
Paper Title Page
THP08 Beam Dynamics Studies for Particle Driven Plasma Wakefield Acceleration Experiments at PITZ 236
 
  • M. Khojoyan, M. Groß, G. Klemz, G. Koss, M. Krasilnikov, A. Oppelt, F. Stephan
    DESY Zeuthen, Zeuthen, Germany
  • M. Khojoyan
    ANSL, Yerevan, Armenia
 
  The Photo Injector Test Facility at DESY, Zeuthen site (PITZ) is developing and optimizing high brightness electron sources for linac based free electron lasers such as FLASH and the European XFEL. The high quality of the 25 MeV electron beam together with the availability of a highly flexible photocathode laser system makes the PITZ injector a perfect facility for variety of experimental studies. Two approaches are of great interest for future applications in the context of particle driven plasma wakefield acceleration experiments: self-modulation and transformer ratio studies. In both cases a high density electron beam is interacting with a plasma which has a density of about 1015 cm-3. ASTRA simulations were done to study the e-beam density along the existing PITZ beamline, especially at two different possible longitudinal positions of the planned plasma cell, in order to reach the particle density required for occurrence of self-modulation. The results of the beam dynamics studies are presented and discussed in this paper.  
 
THACC3 Preliminary Study of Single Spike SASE FEL Operation at 0.26 Nanometers Wavelength for the European XFEL 253
 
  • B. Marchetti, M. Krasilnikov, F. Stephan
    DESY Zeuthen, Zeuthen, Germany
  • M. Dohlus, Y.A. Kot, I. Zagorodnov
    DESY, Hamburg, Germany
  • J. Rönsch-Schulenburg
    Uni HH, Hamburg, Germany
 
  The production of ultra-short (fs or sub-fs long), high power, radiation pulses in the X-ray spectral region, showing a single spike spectrum, represents a challenge for many existent SASE- FELs [1, 2]. In order to realize single spike operation the length of the electron bunch after compression must be extremely small [3] (less than a micrometer) and the consequent degradation of its emittance has not to suppress the radiation production. Several technical restrictions, such as limits of diagnostics for small charges, RF jitter and micro-bunching instabilities play an important role in the choice of the operation working point. In this paper we are going to study the feasibility of single spike or few spikes lasing for bunches with charge of tens of pC in the European XFEL facility giving some preliminary results concerning the choice of the working point.
[1] J.B. Rosenzweig et al., NIM A 593 (2008) 39-44
[2] S. Reiche et al., NIM A 593 (2008) 45-48
[3] R. Bonifacio et al., PRL vol. 73 n.1 (1994)
 
slides icon Slides THACC3 [1.401 MB]  
 
THP13 Emission Studies of Photocathode RF Gun at PITZ 242
 
  • J. Li, G. Asova, M. Groß, L. Hakobyan, I.I. Isaev, Ye. Ivanisenko, M. Khojoyan, G. Klemz, G. Kourkafas, M. Krasilnikov, K. Kusoljariyakul, M. Mahgoub, D. Malyutin, B. Marchetti, A. Oppelt, B. Petrosyan, S. Rimjaem, A. Shapovalov, F. Stephan, G. Vashchenko
    DESY Zeuthen, Zeuthen, Germany
  • G. Feng
    DESY, Hamburg, Germany
  • D. Richter
    HZB, Berlin, Germany
  • L. Shang
    USTC/NSRL, Hefei, Anhui, People's Republic of China
 
  The Photo Injector Test facility at DESY, Zeuthen site (PITZ), was built to develop and optimize electron sources for linac based Free Electron Lasers(FELs) like FLASH and the European XFEL. For the value of the bunch charge extracted from a photocathode, discrepancy has been observed between the data measured at PITZ and simulation results from the ASTRA code. As a factor which could explain the discrepancy, a Schottky-like effect is considered. Meanwhile, the Parmela code was applied to the emission studies on the PITZ gun as benchmark. Since Parmela cannot be used to simulate a Schottky-like effect with its own modules, MATLAB scripts have been developed to implement this feature of the photoemission in an RF gun.