FEL2012 - List of Authors (Froehlich, L.)

Paper

Title

Page

First Lasing of FERMI FEL-2 (1° Stage) and FERMI FEL-1 Recent Results

13

L. Giannessi, E. Allaria, L. Badano, D. Castronovo, P. Cinquegrana, P. Craievich, G. D'Auria, M.B. Danailov, A.A. Demidovich, S. Di Mitri, B. Diviacco, W.M. Fawley, E. Ferrari, L. Fröhlich, G. Gaio, R. Ivanov, E. Karantzoulis, B. Mahieu, N. Mahne, I. Nikolov, G. Penco, L. Raimondi, C. Serpico, P. Sigalotti, S. Spampinati, C. Spezzani, M. Svandrlik, C. Svetina, M. Trovò, M. Veronese, D. Zangrando, M. Zangrando
Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
G. De Ninno
University of Nova Gorica, Nova Gorica, Slovenia
F. Parmigiani
Università degli Studi di Trieste, Trieste, Italy

The FERMI@Elettra seeded Free Electron Laser (FEL) is based on two complementary FEL lines, FEL-1 and FEL-2. FEL-1 is a single stage cascaded FEL delivering light in the 80-20nm wavelength range, while FEL-2 is a double stage cascaded FEL where the additional stage should extend the frequency up-conversion to the spectral range of 20-4nm. The FEL-1 beam line is in operation since the end of 2010, with user experiments carried on in 2011 and 2012. During 2012 the commissioning of the FEL-2 beam line has started and the first observation of coherent light from the first stage of the cascade has been demonstrated. In the meanwhile the commissioning of a number of key components of FERMI, as the laser heater, the X-Band cavity for the longitudinal phase space linearization and the high energy RF deflector has been completed. The additional control on the longitudinal phase space and a progressive improvement in the machine optics optimization had a significant impact of FEL-1 performances, which has reached the expected specifications. In addition, emission of radiation at very high order conversion factors (up to 29th) has been observed and double stage cascades have been preliminarily tested with the observation of coherent radiation in the water window, up to the 65th harmonic of the seed laser, at about 4 nm.

Slides MOOB06 [6.633 MB]

TUOB02

Spectral Characterization of the FERMI Pulses in the Presence of Electron-beam Phase-space Modulations

213

E. Allaria, S. Di Mitri, W.M. Fawley, E. Ferrari, L. Fröhlich, L. Giannessi, B. Mahieu, G. Penco, C. Spezzani, M. Trovò
Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
G. De Ninno, S. Spampinati
University of Nova Gorica, Nova Gorica, Slovenia

As a seeded FEL based on a single stage HGHG configuration, FERMI's FEL-1 has produced very narrow bandwidth FEL pulses in the XUV wavelength region relative to those typical of SASE devices. This important feature of seeded FELs relies however upon the capability to produce high quality electron beams and with clean longitudinal phase spaces. As has been predicted previously, the FEL output spectra can be modified from a simple, nearly transform-limited single spike by modulation and distortions of the longitudinal phase space of the electron beam. In this work we report a study of the FEL spectra recorded at FERMI for various situations showing the effects of phase-space modulation on the FEL properties.

Slides TUOB02 [4.376 MB]

WEOA03

Machine Protection for Single-Pass FELs

345

L. Fröhlich
Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy

The linacs driving modern single-pass FELs carry electron beams of unprecedented brightness. Their average power ranges from few watts to hundreds of kilowatts. At the same time, these machines are equipped with unusual amounts of instrumentation that need to be protected from beam losses. The FEL process itself depends crucially on the precision of the magnetic field inside undulator structures that are prone to demagnetization under radiation exposure. This combination makes machine protection for FELs both a necessity and a challenge. The talk gives an overview of typical hazards and of machine protection strategies adopted at FELs in various laboratories.

Slides WEOA03 [1.375 MB]

Paper	Title	Page
MOOB06	First Lasing of FERMI FEL-2 (1° Stage) and FERMI FEL-1 Recent Results	13
	L. Giannessi, E. Allaria, L. Badano, D. Castronovo, P. Cinquegrana, P. Craievich, G. D'Auria, M.B. Danailov, A.A. Demidovich, S. Di Mitri, B. Diviacco, W.M. Fawley, E. Ferrari, L. Fröhlich, G. Gaio, R. Ivanov, E. Karantzoulis, B. Mahieu, N. Mahne, I. Nikolov, G. Penco, L. Raimondi, C. Serpico, P. Sigalotti, S. Spampinati, C. Spezzani, M. Svandrlik, C. Svetina, M. Trovò, M. Veronese, D. Zangrando, M. Zangrando Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy G. De Ninno University of Nova Gorica, Nova Gorica, Slovenia F. Parmigiani Università degli Studi di Trieste, Trieste, Italy
	The FERMI@Elettra seeded Free Electron Laser (FEL) is based on two complementary FEL lines, FEL-1 and FEL-2. FEL-1 is a single stage cascaded FEL delivering light in the 80-20nm wavelength range, while FEL-2 is a double stage cascaded FEL where the additional stage should extend the frequency up-conversion to the spectral range of 20-4nm. The FEL-1 beam line is in operation since the end of 2010, with user experiments carried on in 2011 and 2012. During 2012 the commissioning of the FEL-2 beam line has started and the first observation of coherent light from the first stage of the cascade has been demonstrated. In the meanwhile the commissioning of a number of key components of FERMI, as the laser heater, the X-Band cavity for the longitudinal phase space linearization and the high energy RF deflector has been completed. The additional control on the longitudinal phase space and a progressive improvement in the machine optics optimization had a significant impact of FEL-1 performances, which has reached the expected specifications. In addition, emission of radiation at very high order conversion factors (up to 29th) has been observed and double stage cascades have been preliminarily tested with the observation of coherent radiation in the water window, up to the 65th harmonic of the seed laser, at about 4 nm.
	Slides MOOB06 [6.633 MB]

TUOB02	Spectral Characterization of the FERMI Pulses in the Presence of Electron-beam Phase-space Modulations	213
	E. Allaria, S. Di Mitri, W.M. Fawley, E. Ferrari, L. Fröhlich, L. Giannessi, B. Mahieu, G. Penco, C. Spezzani, M. Trovò Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy G. De Ninno, S. Spampinati University of Nova Gorica, Nova Gorica, Slovenia
	As a seeded FEL based on a single stage HGHG configuration, FERMI's FEL-1 has produced very narrow bandwidth FEL pulses in the XUV wavelength region relative to those typical of SASE devices. This important feature of seeded FELs relies however upon the capability to produce high quality electron beams and with clean longitudinal phase spaces. As has been predicted previously, the FEL output spectra can be modified from a simple, nearly transform-limited single spike by modulation and distortions of the longitudinal phase space of the electron beam. In this work we report a study of the FEL spectra recorded at FERMI for various situations showing the effects of phase-space modulation on the FEL properties.
	Slides TUOB02 [4.376 MB]

WEOA03	Machine Protection for Single-Pass FELs	345
	L. Fröhlich Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
	The linacs driving modern single-pass FELs carry electron beams of unprecedented brightness. Their average power ranges from few watts to hundreds of kilowatts. At the same time, these machines are equipped with unusual amounts of instrumentation that need to be protected from beam losses. The FEL process itself depends crucially on the precision of the magnetic field inside undulator structures that are prone to demagnetization under radiation exposure. This combination makes machine protection for FELs both a necessity and a challenge. The talk gives an overview of typical hazards and of machine protection strategies adopted at FELs in various laboratories.
	Slides WEOA03 [1.375 MB]