FEL2012 - List of Authors (Cocco, D.)

Paper

Title

Page

System Design for Self-Seeding the LCLS at Soft X-ray Energies

205

Y. Feng, J.W. Amann, D. Cocco, R.C. Field, J.B. Hastings, P.A. Heimann, Z. Huang, H. Loos, J.J. Welch, J. Wu
SLAC, Menlo Park, California, USA
K. Chow, P. Emma, L. Rodes, R.W. Schoenlein
LBNL, Berkeley, California, USA

Funding: Portions of this research were carried out at the LCLS at the SLAC. LCLS is an Office of Science User Facility operated for the U.S. DOE Office of Science by Stanford University
The complete design for self-seeding the LCLS at soft X-ray energies from 400 to 1000 eV based on a grating monochromator is described. The X-ray optics system consists of a toroidal variable-line-space (VLS) grating with a resolving power greater than 5000 for creating a nearly transform-limited seed pulse from the upstream SASE undulator for pulse durations of the order of 25 fs, and focusing mirrors for imaging the seed pulse onto the downstream seeding undulator. Diagnostics for ensuring overlap with the reentrant electron beam are included in the design. The optical system is sufficiently compact to fit within a single 3.4 m LCLS undulator segment. The electron chicane system which serves to delay the electron beam to match the less than 1 ps delay from the optical system is similar to the chicane used in the hard X-ray self-seeding at LCLS. The seeded FEL pulse is expected to be nearly transform-limited with a bandwidth in the 10-4 range, potentially increasing the low-charge FEL X-ray peak brightness by 1-2 orders of magnitude.

Slides TUOBI01 [6.749 MB]

THOA02

Photon Beam Transport Systems at FERMI@Elettra: Microfocusing FEL Beam with a K-B Active Optics System

L. Raimondi, A. Abrami, F. Capotondi, M. De Marco, C. Fava, S. Gerusina, R. Gobessi, M. Kiskinova, N. Mahne, E. Mazzucco, F. Parmigiani, E. Pedersoli, L. Rumiz, G. Sostero, C. Svetina
Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
D. Cocco
SLAC, Menlo Park, California, USA
M. Zangrando
IOM-CNR, Trieste, Italy

FERMI@Elettra, the first seeded EUV-SXR FEL facility, located at Sincrotrone Trieste S.C.p.A., is under advanced commissioning. It will provide ultrashort (10-100 fs) pulses with high peak brightness in the range 100-4 nm. The photon diagnostics section (PADReS) has been installed and commissioned during the last years. Three of the four installed beam lines (EIS-TIMER, EIS-TIMEX, DiProI and LDM) will employ active X-ray optics for focusing and beam-shaping. For DiProI and LDM the beam focusing is accomplished by K-B active X-ray optic mirrors to reach the fundamental diffraction limit. This system allows work with the two different undulator chains FEL1 and FEL2, which have different source locations, and perform an accurate mirror shaping and wave front optimization. In this work we present preliminary results of measurements with the DiProI beamline end-station. A focal spot size <20 μm at 32 nm has been obtained. We also compare these measurements with the predictions computed with a numerical method based on physical optics (Raimondi-Spiga Code [1]) starting from the mirror surface profile characterization. Measurements and simulations are in agreement.
[1] Raimondi L., Spiga D., 2011, in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series Vol. 8147 of Society

Slides THOA02 [5.317 MB]

Paper	Title	Page
TUOBI01	System Design for Self-Seeding the LCLS at Soft X-ray Energies	205
	Y. Feng, J.W. Amann, D. Cocco, R.C. Field, J.B. Hastings, P.A. Heimann, Z. Huang, H. Loos, J.J. Welch, J. Wu SLAC, Menlo Park, California, USA K. Chow, P. Emma, L. Rodes, R.W. Schoenlein LBNL, Berkeley, California, USA
	Funding: Portions of this research were carried out at the LCLS at the SLAC. LCLS is an Office of Science User Facility operated for the U.S. DOE Office of Science by Stanford University The complete design for self-seeding the LCLS at soft X-ray energies from 400 to 1000 eV based on a grating monochromator is described. The X-ray optics system consists of a toroidal variable-line-space (VLS) grating with a resolving power greater than 5000 for creating a nearly transform-limited seed pulse from the upstream SASE undulator for pulse durations of the order of 25 fs, and focusing mirrors for imaging the seed pulse onto the downstream seeding undulator. Diagnostics for ensuring overlap with the reentrant electron beam are included in the design. The optical system is sufficiently compact to fit within a single 3.4 m LCLS undulator segment. The electron chicane system which serves to delay the electron beam to match the less than 1 ps delay from the optical system is similar to the chicane used in the hard X-ray self-seeding at LCLS. The seeded FEL pulse is expected to be nearly transform-limited with a bandwidth in the 10-4 range, potentially increasing the low-charge FEL X-ray peak brightness by 1-2 orders of magnitude.
	Slides TUOBI01 [6.749 MB]

THOA02	Photon Beam Transport Systems at FERMI@Elettra: Microfocusing FEL Beam with a K-B Active Optics System
	L. Raimondi, A. Abrami, F. Capotondi, M. De Marco, C. Fava, S. Gerusina, R. Gobessi, M. Kiskinova, N. Mahne, E. Mazzucco, F. Parmigiani, E. Pedersoli, L. Rumiz, G. Sostero, C. Svetina Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy D. Cocco SLAC, Menlo Park, California, USA M. Zangrando IOM-CNR, Trieste, Italy
	FERMI@Elettra, the first seeded EUV-SXR FEL facility, located at Sincrotrone Trieste S.C.p.A., is under advanced commissioning. It will provide ultrashort (10-100 fs) pulses with high peak brightness in the range 100-4 nm. The photon diagnostics section (PADReS) has been installed and commissioned during the last years. Three of the four installed beam lines (EIS-TIMER, EIS-TIMEX, DiProI and LDM) will employ active X-ray optics for focusing and beam-shaping. For DiProI and LDM the beam focusing is accomplished by K-B active X-ray optic mirrors to reach the fundamental diffraction limit. This system allows work with the two different undulator chains FEL1 and FEL2, which have different source locations, and perform an accurate mirror shaping and wave front optimization. In this work we present preliminary results of measurements with the DiProI beamline end-station. A focal spot size <20 μm at 32 nm has been obtained. We also compare these measurements with the predictions computed with a numerical method based on physical optics (Raimondi-Spiga Code [1]) starting from the mirror surface profile characterization. Measurements and simulations are in agreement. [1] Raimondi L., Spiga D., 2011, in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series Vol. 8147 of Society
	Slides THOA02 [5.317 MB]