Author: Cudin, I.
Paper Title Page
MOD04 Status and Perspectives of the FERMI FEL Facility 1
  • L. Giannessi, E. Allaria, L. Badano, F. Bencivenga, C. Callegari, F. Capotondi, F. Cilento, P. Cinquegrana, M. Coreno, I. Cudin, G. D'Auria, M.B. Danailov, R. De Monte, G. De Ninno, P. Delgiusto, A.A. Demidovich, M. Di Fraia, S. Di Mitri, B. Diviacco, A. Fabris, R. Fabris, W.M. Fawley, M. Ferianis, P. Furlan Radivo, G. Gaio, D. Gauthier, F. Gelmetti, F. Iazzourene, S. Krecic, M. Lonza, N. Mahne, M. Malvestuto, C. Masciovecchio, M. Milloch, N.S. Mirian, F. Parmigiani, G. Penco, A. Perucchi, L. Pivetta, O. Plekan, M. Predonzani, E. Principi, L. Raimondi, P. Rebernik Ribič, F. Rossi, E. Roussel, L. Rumiz, C. Scafuri, C. Serpico, P. Sigalotti, S. Spampinati, C. Spezzani, M. Svandrlik, M. Trovò, A. Vascotto, M. Veronese, R. Visintini, D. Zangrando, M. Zangrando
    Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
  FERMI is the seeded Free Electron Laser (FEL) user facility at the Elettra laboratory in Trieste, operating in the VUV to EUV and soft X-rays spectral range; the radiation produced by the seeded FEL is characterised by a number of desirable properties, such as wavelength stability, low temporal jitter and longitudinal coherence. In this paper, after an overview of the FELs performances, we will present the development plans under consideration for the next 3 to 5 years. These include an upgrade of the LINAC and of the existing FEL lines, the possibility to perform multi-pulse experiments in different configurations and an Echo Enabled Harmonic Generation experiment on FEL-2, the FEL line extending to 4 nm (310 eV).  
Towards the Demonstration of Soft X-Ray Echo-Enabled Harmonic Generation at Fermi  
  • E. Allaria, R. Bracco, D. Castronovo, I. Cudin, M.B. Danailov, G. De Ninno, S. Di Mitri, B. Diviacco, W.M. Fawley, M. Ferianis, L. Giannessi, M. Lonza, G. Penco, P. Rebernik Ribič, E. Roussel, S. Spampinati, C. Spezzani, L. Sturari, M. Svandrlik, M. Veronese, R. Visintini, M. Zaccaria, D. Zangrando
    Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
  • H.-H. Braun, E. Prat, S. Reiche
    PSI, Villigen PSI, Switzerland
  • G. De Ninno
    University of Nova Gorica, Nova Gorica, Slovenia
  • B.W. Garcia, J.B. Hastings, E. Hemsing, T.O. Raubenheimer, G. Stupakov, J.J. Welch
    SLAC, Menlo Park, California, USA
  • G. Penn
    LBNL, Berkeley, California, USA
  • E. Roussel
    SOLEIL, Gif-sur-Yvette, France
  • A. Zholents
    ANL, Argonne, Illinois, USA
  The echo-enabled harmonic generation seeding scheme is based on an echo mechanism that develops in the electron beam phase-space interacting with two seed lasers before and after a strong dispersive region. It has been proposed for extending the capabilities of externally seeded free electron lasers to reach short wavelengths. After the original proposal, a few experiments have confirmed the capabilities of efficient bunching generation at very high harmonics. However, up to now none of the experiments demonstrated FEL amplification from high harmonic bunching produced at 10 nm wavelengths or shorter. In this work, we report about our plans for performing an EEHG experiment at FERMI. The experiment will be done at the FEL-2 line normally operated in the double stage high-gain harmonic generation configuration in the wavelength range 20-4 nm. After the modification of a few hardware components planned for the first semester of 2018, the FEL-2 layout will be suitable for EEHG at wavelengths down to approximately 6 nm.  
Passive Linearization of the Magnetic Bunch Compression Using Self-Induced Field and Without Any Active Higher Harmonic RF Structure  
  • G. Penco, E. Allaria, I. Cudin, S. Di Mitri, D. Gauthier, L. Giannessi, E. Roussel, S. Spampinati, M. Trovò
    Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
  • S. Bettoni, P. Craievich, E. Ferrari
    PSI, Villigen PSI, Switzerland
  • L. Giannessi
    ENEA C.R. Frascati, Frascati (Roma), Italy
  • E. Roussel
    SOLEIL, Gif-sur-Yvette, France
  In linac-driven free-electron lasers, colliders and energy recovery linacs, a common way to compress the electron bunch to kA level is based upon the implementation of a magnetic dispersive element that converts the bunch energy deviation in path-length difference. The non-linearities of such a process are usually compensated by enabling a high harmonic rf structure properly tuned in amplitude and phase. This approach is however not straightforward for foreseen C and X-band linacs. In this work we report the experiment performed on the FERMI linac that has demonstrated the possibility to exploit the longitudinal self-induced field excited by the electron beam itself to passively linearize the compression process without any active higher harmonic rf structure. In this novel configuration, the FERMI electron bunch was compressed up to 700 A as in the nominal case and driven along the FERMI FEL-1 undulators, generating intense extreme-ultraviolet pulses that were provided to users for experiments.