Author: Di Palma, E.
Paper Title Page
Two Color Experiments at SPARC: External and Intra-bunch Seeding  
  • D. Alesini, M.P. Anania, M. Bellaveglia, M. Castellano, E. Chiadroni, D. Di Giovenale, G. Di Pirro, M. Ferrario, A. Gallo, G. Gatti, R. Pompili, S. Romeo, V. Shpakov, C. Vaccarezza, F. Villa
    INFN/LNF, Frascati (Roma), Italy
  • M. Artioli
    ENEA-Bologna, Bologna, Italy
  • A. Bacci, A.R. Rossi
    Istituto Nazionale di Fisica Nucleare, Milano, Italy
  • M.C. Carpanese, F. Ciocci, G. Dattoli, E. Di Palma, L. Giannessi, A. Petralia, E. Sabia, I.P. Spassovsky
    ENEA C.R. Frascati, Frascati (Roma), Italy
  • A. Cianchi
    INFN-Roma II, Roma, Italy
  • F. Filippi, A. Giribono
    INFN-Roma, Roma, Italy
  • L. Innocenti
    Università di Roma II Tor Vergata, Roma, Italy
  • N.S. Mirian, V. Petrillo
    Universita' degli Studi di Milano & INFN, Milano, Italy
  • A. Mostacci
    Rome University La Sapienza, Roma, Italy
  • J.V. Rau
    ISM-CNR, Rome, Italy
  The FEL-SPARC operation with two bunches at different energies has been characterized using different tools. The effect of the e-beam matching on the SASE operation has been explored by controlling the transport with an ad hoc developed control system, allowing either the transport in matching conditions and in different configurations. Since the two bunches have, at the entrance of the undulator, different phase space characteristics we used this effect as a knob to enhance or suppress one or the other FEL mode. We investigated the effect of seeding on both frequencies and observed beating waves, furthermore we observed effects of intra-bunch seeding when only one of the modes is seeded.  
Thoughts on the New Technologies for Compact FEL Devices  
  • S. Biedron, J. Einstein, S.V. Milton
    CSU, Fort Collins, Colorado, USA
  • G. Dattoli, E. Di Palma, E. Sabia, I.P. Spassovsky
    ENEA C.R. Frascati, Frascati (Roma), Italy
  • V. Petrillo
    Universita' degli Studi di Milano, Milano, Italy
  • J.V. Rau
    ISM-CNR, Rome, Italy
  The possibility to merge different solutions exploiting wave undulators, laser plasma acceleration and other schemes, allows the design of compact Free Electron Laser (FEL) sources operating in the extreme UV-X-ray region of the spectrum. Newly developed high peak power lasers have opened indeed effective possibilities of driving coherent light sources operating with laser plasma accelerated beams and wave undulators. We combine different ideas including also the concept of sheared beam configuration to achieve compact and reliable FEL devices. We finally comment on the perspective use of Radio Frequency (RF) undulators, which seems to be fairly good candidates for opening a new technological strategy for the design of FEL oscillators, including bi-harmonic and multi-frequency operation.