Author: Mirian, N.S.
Paper Title Page
TUP006 Two-color Free-electron Laser via Two Orthogonal Undulators 358
  • N.S. Mirian
    IPM, Tehran, Iran
  • G. Dattoli
    ENEA C.R. Frascati, Frascati (Roma), Italy
  • V. Petrillo
    Universita' degli Studi di Milano, Milano, Italy
  An amplifier Free electron Laser (FEL) including two orthogonal polarized undulators with different periods and field intensities is able to emit two color radiations with different frequency and polarization while the total length of device does not change respect to usual single color FELs. The wavelengths of two different colors can be changed by choosing different periods, while variation in the magnetic strengths can be used to modify the gain lengths.  
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.