FEL2011 - List of Authors (Vicario, C.)

Paper

Title

Page

WEOCI2

Ultrashort Single Spike Pulse Generation at the SPARC Test Facility

D. Filippetto
LBNL, Berkeley, California, USA
A. Bacci, M. Bellaveglia, M. Castellano, E. Chiadroni, L. Cultrera, G. Di Pirro, M. Ferrario, L. Ficcadenti, A. Gallo, G. Gatti, E. Pace, B. Spataro, C. Vaccarezza, C. Vicario
INFN/LNF, Frascati (Roma), Italy
A. Cianchi
Università di Roma II Tor Vergata, Roma, Italy
F. Ciocci, G. Dattoli, M. Del Franco, L. Giannessi, A. Petralia, M. Quattromini, C. Ronsivalle, E. Sabia, I.P. Spassovsky, V. Surrenti
ENEA C.R. Frascati, Frascati (Roma), Italy
F. Frassetto, L. P. Poletto
LUXOR, Padova, Italy
M. Moreno, M. Serluca
INFN-Roma, Roma, Italy
A. Mostacci
Rome University La Sapienza, Roma, Italy
V. Petrillo, A.R. Rossi
Istituto Nazionale di Fisica Nucleare, Milano, Italy
J.V. Rau, V. Rossi Albertini
ISM-CNR, Rome, Italy

We report the first experimental implementation of a method based on simultaneous use of an energy chirp in the electron beam and a tapered undulator, for the generation of ultrashort pulses in a Self Amplified Spontaneous Emission mode Free Electron Laser (SASE FEL). The experiment, performed at the SPARC FEL test facility, demonstrates the possibility of compensating the nominally detrimental effect of the chirp by a proper taper of the undulator gaps. Longitudinal phase space rotation via velocity bunching is used to generate the energy chirp, which also increases the peak current and the FEL performances. An increase of more than one order of magnitude in the pulse energy is observed in comparison to the untapered case, accompanied by FEL spectra where the typical SASE spiking is suppressed.

Slides WEOCI2 [16.008 MB]

TUOCI1

Latest Developments for Photoinjector, Seeding and THz Laser Systems

173

C.P. Hauri, A. Trisorio, C. Vicario
Paul Scherrer Institut, Villigen, Switzerland
C. Ruchert
PSI, Villigen PSI, Switzerland

For driving compact FEL facilities cutting edge laser technology is required. We present the latest laser developments and concepts for ultrastable and versatile electron gun lasers, seed lasers and high-power laser-based THz sources taking place at the Paul Scherrer Institute and at other Free Electron Laser facilities. Such developments are of fundamental interest for next generation FEL pump-probe experiments requiring a temporal resolution beyond state of the art.

Slides TUOCI1 [5.159 MB]

THPB06

Coherent Terahertz Radiation Monitors for Multiple Spectral Bands

572

R. Ischebeck, G.L. Orlandi, P. Peier, V. Schlott, B. Smit, C. Vicario, C. Zimmerli
Paul Scherrer Institut, Villigen, Switzerland
C. Gerth
DESY, Hamburg, Germany

The SwissFEL Injector Test Facility is destined for demonstrating electron beam parameters that are suitable for FEL operation. Of particular interest is the on-line measurement of longitudinal phase space properties, as this provides insight into the bunch compression process. The spectral distribution of diffraction radiation offers a robust way to assess bunch length and longitudinal profile. The bunch length at the SwissFEL Injector Test Facility can be varied by changing the photocathode laser. Diffraction radiation is emitted as the electron bunches pass through a hole in a titanium foil. The emitted Terahertz radiation has been simulated by the code THz Transport, and the propagation to the detectors has been modeled.

THPB30

SwissFEL Injector Test Facility – Test and Plans

625

M. Pedrozzi, M. Aiba, S. Bettoni, B. Beutner, A. Falone, R. Ganter, R. Ischebeck, F. Le Pimpec, G.L. Orlandi, E. Prat, S. Reiche, T. Schietinger, A. Trisorio, C. Vicario
Paul Scherrer Institut, Villigen, Switzerland

In August 2010 the Paul Scherrer Institute inaugurated the SwissFEL Injector test facility as a first step toward the Swiss hard X-ray FEL planned at PSI. The main purpose of the facility is to demonstrate and consolidate the generation of high-brightness beam as required to drive the 6 GeV SwissFEL accelerator. Additionally the injector serves as a platform supporting development and test of accelerator components/systems and optimization procedures foreseen for SwissFEL. In this paper we report on the present status of the commissioning with some emphasis on emittance measurements and component performances. The scientific program and long-term plans will be discussed as well.

WEOB3

Seeding Experiments at SPARC

M. Labat, F. Briquez, M.-E. Couprie
SOLEIL, Gif-sur-Yvette, France
D. Alesini, M. Bellaveglia, M. Castellano, E. Chiadroni, G. Di Pirro, A. Drago, M. Ferrario, L. Ficcadenti, A. Gallo, G. Gatti, A. Ghigo, E. Pace, B. Spataro, C. Vaccarezza
INFN/LNF, Frascati (Roma), Italy
A. Bacci, V. Petrillo, A.R. Rossi, L. Serafini
Istituto Nazionale di Fisica Nucleare, Milano, Italy
M. Bougeard, B. Carré, D. Garzella
CEA/DSM/DRECAM/SPAM, Gif-sur-Yvette, France
A. Cianchi
Università di Roma II Tor Vergata, Roma, Italy
F. Ciocci, G. Dattoli, M. Del Franco, L. Giannessi, A. Petralia, M. Quattromini, C. Ronsivalle, E. Sabia, I.P. Spassovsky, V. Surrenti
ENEA C.R. Frascati, Frascati (Roma), Italy
L. Cultrera
CLASSE, Ithaca, New York, USA
D. Filippetto
LBNL, Berkeley, California, USA
F. Frassetto, L. P. Poletto
LUXOR, Padova, Italy
G. Lambert
LOA, Palaiseau, France
G. Marcus, J.B. Rosenzweig
UCLA, Los Angeles, California, USA
M. Migliorati, A. Mostacci, L. Palumbo
Rome University La Sapienza, Roma, Italy
J.V. Rau
ISM-CNR, Rome, Italy
M. Serluca
INFN-Roma, Roma, Italy
C. Vicario
PSI, Villigen PSI, Switzerland

The SPARC FEL amplifier has been configured as a single stage HGHG FEL with a modulator and a radiator operating at the second harmonic. The HGHG cascade has been seeded with harmonics generated in a gas cell where a Ti:Sa laser pulse of 120 fs of duration is converted into higher harmonics. The cascaded FEL configuration obtained by tuning the undulator gaps has been studied by varying the number of modulators and radiators to optimize the conversion efficiency. The process of harmonic generation in a free electron laser operating in superradiant regime has been also analysed. Harmonic generation is expected to be efficient because of the quasi steady-state distribution of the e-beam phase space predicted in this regime. Harmonics up to the 11th have been experimentally observed.

Slides WEOB3 [5.198 MB]