Author: Ferianis, M.
Paper Title Page
MOPC04 Electron Beam Collimation for Slice Diagnostics and Generation of Femtosecond Soft X-Ray Pulses from a Free Electron Laser 49
  • S. Di Mitri, M. Bossi, D. Castronovo, I. Cudin, M. Ferianis, L. Fröhlich
    Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
  We present the experimental results of femtosecond slicing an ultra-relativistic, high brightness electron beam with a collimator*. We demonstrate that the collimation process preserves the slice beam quality, in agreement with our theoretical expectations, and that the collimation is compatible with the operation of a linear accelerator. Thus, it turns out to be a more compact and cheaper solution for electron slice diagnostics than commonly used radiofrequency deflecting cavities and having minimal impact on the machine design. The collimated beam can also be used for the generation of stable femtosecond soft x-ray pulses of tunable duration from a free electron laser.
* S. Di Mitri et al., Phys. Rev. Special Topics - Accel. Beams 16, 042801 (2013).
TUAL1 Longitudinal Phase Space Characterization at FERMI@Elettra 303
  • E. Ferrari, E. Allaria, P. Cinquegrana, M. Ferianis, L. Fröhlich, L. Giannessi, G. Penco, M. Predonzani, F. Rossi, P. Sigalotti, M. Veronese
    Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
  • E. Ferrari
    Università degli Studi di Trieste, Trieste, Italy
  The seeded FEL FERMI@Elettra has completed the commissioning of FEL1 line, and it is now providing the User Community with a coherent and tunable UV radiation (from 70nm to 20nm) in a number of different configurations, including an original twin-seeded pump-probe scheme. Among the key sub systems for the operation of FERMI@Elettra, there are the femto second optical timing system, some dedicated longitudinal diagnostics, specifically developed for FERMI@Elettra and, of course, state of art laser systems. In this paper, after a short review of the FERMI@Elettra optical timing system and of its routinely achieved performances, we focus on the results obtained from the suite of longitudinal diagnostics (Bunch Arrival Monitor, Electro Optical sampling station and RF deflectors) all operating in single shot and with 10s fs resolution which demonstrate the FERMI@Elettra achieved performances. The results from these longitudinal diagnostics are compared and shot to shot correlated with the results obtained from an independent longitudinal measurement technique, based on a spectrometer measurement of a linearly chirped electron bunch, which further validate the FERMI@Elettra operation.  
slides icon Slides TUAL1 [10.689 MB]  
WEPF27 Coherent Ultraviolet Radiation Measurements of Laser Induced Bunching in a Seeded FEL 879
  • M. Veronese, A. Abrami, E. Allaria, M. Ferianis, E. Ferrari, M. Trovò
    Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
  • F. Cianciosi
    ESRF, Grenoble, France
  Optimization of the bunching process in a seeded FEL like FERMI@Elettra is an important aspect for machine operation. In this paper we discuss about the power detection of coherent radiation in the UV range as a valuable method for optimizing the bunching induced by the seeding process on the electron beam. Experimental results obtained at FERMI@Elettra are presented here. Measurements of UV coherent transition and diffraction radiation have been used to quantify the bunching produced by the seed laser at lower laser harmonics. The dependence of the laser induced CUVTR signal on various parameters is experimentally studied. Future upgrades and possibilities for bunching measurements at shortest wavelengths are also discussed.