Author: Penco, G.
Paper Title Page
MOEPPB014 Time Jitter Measurements in Presence of a Magnetic Chicane in the FERMI@elettra Linac 109
  • G. Penco, P. Craievich, S. Di Mitri, M.M. Milloch, F. Rossi
    ELETTRA, Basovizza, Italy
  Accurate and highly stable temporal synchronization between an electron bunch and a pulse from an external seed laser is one of the key requirements for successful operation of a seeded FEL in the XUV and soft x-ray regime. These requirements become more stringent when the electron bunch is longitudinally compressed to sub-ps durations in order to increase the current for more efficient FEL action. In this paper we present experimental measurements of the electron bunch arrival time jitter after the first magnetic compressor of FERMI@Elettra seeded FEL as a function of the compression factor. The experimental behavior of the pulse-to-pulse time jitter agrees both with results from tracking code simulations and with predictions from an analytical approach that takes into account the different sources of time jitter in FERMI, namely the photoinjector drive laser, the RF accelerating cavity phases and voltages, and fluctuations in the chicane bending magnet currents. We also present predictions for the expected arrival time jitter in the final configuration of FERMI that includes two bunch compressors and for which the synchronization requirement is of order 100 fs or better.  
TUPPP054 RF Activation and Preliminary Beam Tests of the X-band Linearizer at the FERMI@Elettra FEL Project 1721
  • G. D'Auria, S. Di Mitri, G. Penco, C. Serpico
    ELETTRA, Basovizza, Italy
  FERMI@Elettra is a fourth generation light source facility presently in commissioning at the Elettra Laboratory in Trieste, Italy. It is based on an S-band (3 GHz), 1.5 GeV normal conducting (NC) linac, that provides ultra short e-bunches with high peak current, using two stages of magnetic compression. To linearize the beam longitudinal phase space and to improve the compression process, a forth harmonic RF structure (12 GHz) has been installed downstream the first magnetic chicane. This paper reports the RF activation of the structure and the preliminary tests performed on the beam.  
TUPPP063 Electron-beam Optimization Studies for the FERMI@Elettra Free-electron Laser 1741
  • E. Ferrari, G. De Ninno
    University of Nova Gorica, Nova Gorica, Slovenia
  • P. Craievich, S. Di Mitri, E. Ferrari, L. Fröhlich, G. Gaio, G. Penco, C. Spezzani, M. Trovò
    ELETTRA, Basovizza, Italy
  FERMI@Elettra is a single-pass free-electron laser, based on seeded high-gain harmonic generation. Presently, the first phase of the project (covering the spectral range between 100 and 20 nm) is under commissioning. The free-electron laser performance depends on the quality of the electron beam. In the case of the FERMI linear accelerator, the latter is strongly influenced both by the wake-fields present in the accelerating sections and by possible misalignments of the various accelerator components. In order to investigate and compensate these effects, we performed a study based on local trajectory bumps. We demonstrate that this approach significantly improves the electron-beam quality and, eventually, the free-electron laser performance.  
TUOBB03 Status of the FERMI@Elettra Project 1092
  • M. Svandrlik, E. Allaria, L. Badano, S. Bassanese, F. Bencivenga, E. Busetto, C. Callegari, F. Capotondi, D. Castronovo, M. Coreno, P. Craievich, I. Cudin, G. D'Auria, M. Dal Forno, M.B. Danailov, R. De Monte, G. De Ninno, A.A. Demidovich, M. Di Fraia, S. Di Mitri, B. Diviacco, A. Fabris, R. Fabris, W.M. Fawley, M. Ferianis, E. Ferrari, L. Fröhlich, P. Furlan Radivo, G. Gaio, L. Giannessi, R. Gobessi, C. Grazioli, E. Karantzoulis, M. Kiskinova, M. Lonza, B. Mahieu, C. Masciovecchio, S. Noè, F. Parmigiani, G. Penco, E. Principi, F. Rossi, L. Rumiz, C. Scafuri, S. Spampinati, C. Spezzani, C. Svetina, M. Trovò, A. Vascotto, M. Veronese, R. Visintini, M. Zaccaria, D. Zangrando, M. Zangrando
    ELETTRA, Basovizza, Italy
  Funding: The work was supported in part by the Italian Ministry of University and Research under grants FIRB-RBAP045JF2 and FIRB-RBAP06AWK3.
The FERMI@Elettra seeded Free Electron Laser has provided the first photons to the experimental stations during 2011. The first FEL line in operation is FEL-1, covering the wavelength range between 100 nm and 20 nm. The facility will be opened to users by the end of 2012. In the meantime the installation of the second FEL line, FEL-2 covering the higher energy range down to 4 nm, is progressing on schedule and first tests have started. A description of the status of the project is presented here.
slides icon Slides TUOBB03 [5.316 MB]  
WEPPR060 Short range wakefields in MAX IV and FERMI Linac 3063
  • O. Karlberg, F. Curbis, S. Thorin, S. Werin
    MAX-lab, Lund, Sweden
  • P. Craievich, E. Ferrari, G. Penco
    ELETTRA, Basovizza, Italy
  Ultra-short electron pulses suffer from transverse wake fields resulting in a degradation of the beam quality. Since transverse emittance is a crucial parameter for possible FEL drivers, a careful characterization of wakefields is necessary in the design and commissioning phase of a high-brightness linear accelerator. In this paper we investigate the effect of short-range transverse wakefields in the MAXIV linac in various compression modes. Estimations of the wake potentials have been done with 3D modeling of the accelerating structures as well as with analytical models.