Free Electron Laser Projects X-FEL and the others S. Bertolucci INFN

European Initiatives

Scientific case: new research frontiers in Atomic, molecular and cluster physics Plasma and warm dense matter Condensed matter physics Material science Femtosecond chemistry Life science Single Biological molecules and clusters Imaging/holography Micro and nano lithography

X-Ray FEL’s are based onSASE (no mirrors !) need Ultra-HighBrightness e- Beams X-Ray FEL’s are based on SASE (no mirrors !) need Ultra-High Brightness e- Beams Self-Amplified-Spontaneous-Emission amplifies the spontaneous radiation exponentially in a single pass Interaction of a bright electron beam with noise in an undulator magnet results in a density modulation of the electron bunch at the optical wavelength: SASE instability leads to COHERENT EMISSION Resonance Condition

Undulator Radiation The electron trajectory is inside the radiation cone if The electron trajectory is determined by the undulator field and the electron energy

Relativistic Mirror Counter propagating pseudo-radiation Compton back-scattered radiation in the moving mirror frame Doppler effect in the laboratory frame TUNABILITY

Due to the finite duration the radiation is not monochromatic but contains a frequency spectrum which is obtained by Fourier transformation of a truncated plane wave

Spectral Intensity Line width

 =  norm. energy  n  = r.m.s. normalized emittance I = peak current K = undulator parameter  u B u A) Photon and Electron Beams must overlap in ph space B) Cold Electron Beam (no damping of instability growth) Conditions for SASE Brightness is what really matters ! R. Saldin et al. in Conceptual Design of a 500 GeV e+e- Linear Collider with Integrated X-ray Laser Facility, DESY

SASE Saturation Results TTF-FEL DESY 98 nm TTF-FEL DESY 98 nm Since September 2000: 3 SASE FEL’s demonstrate saturation Since September 2000: 3 SASE FEL’s demonstrate saturation LEUTL APS/ANL 385 nm LEUTL APS/ANL 385 nm September 2000 VISA ATF/BNL 840 nm VISA ATF/BNL 840 nm March 2001

TTF FEL LEUTL

LCLS Overview Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center ESFRI Workshop 30 October 2003 John N. Galayda, SLAC Linac Coherent Light Source Project Description SLAC Linac Two Chicanes for bunch compression Undulator Hall Near Hall Far Hall Injector

LCLS Overview Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center ESFRI Workshop 30 October 2003 Estimated Cost, Revised Schedule $200M-$240M Total Estimated Cost range $245M-$295M Total Project Cost range FY2005Long-lead purchases for injector, undulator FY2006 Construction begins January 2008 FEL Commissioning begins September 2008 Construction complete $200M-$240M Total Estimated Cost range $245M-$295M Total Project Cost range FY2005Long-lead purchases for injector, undulator FY2006 Construction begins January 2008 FEL Commissioning begins September 2008 Construction complete FY2008FY2009 ConstructionOperation FY2001FY2002FY2003FY2004FY2005FY2006FY2007 CD-1CD-2a CD-2b CD-3a CD-3b CD-0 Title I Design Complete XFEL Commissioning CD-4

LCLS Overview Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center ESFRI Workshop 30 October 2003 John N. Galayda, SLAC Capabilities Spectral coverage: nm Peak Brightness: Average Brightness: 3 x Pulse duration: <230 fsec Pulse repetition rate: 120 Hz Photons/pulse: To 0.5 Ǻ in 3 rd harmonic

 =  norm. energy  n  = r.m.s. normalized emittance I = peak current K = undulator parameter  u B u A) Photon and Electron Beams must overlap in ph space B) Cold Electron Beam (no damping of instability growth) Conditions for SASE Brightness is what really matters ! R. Saldin et al. in Conceptual Design of a 500 GeV e+e- Linear Collider with Integrated X-ray Laser Facility, DESY

Photo-Injector Beam dynamics R&D challenges for future X-ray sources Three Major Tasks to accomplish: 1.Minimize all mechanisms leading to degradation of the rms normalized transverse emittance en 2.Peak current enhancement by a factor Damp the beam energy spread below the threshold  /  < 

S orgente P ulsata A uto-amplificata R adiazione C oerente Self-Amplified Pulsed Coherent LNF

SPARC project R&D program towards: - high brightness 150 MeV electron beam, - a SASE-FEL experiment - Ultrashort X-ray generation - X-ray optics & diagnostics

Under INFN responsibility SPARC 3D CAD model Under ENEA responsibility

SPARC Brightness State of the Art PITZ ATF SUMITOMO

Innovative Concepts / Components to reach max. brightness Use of Shaped Laser PulsesUse of Shaped Laser Pulses (minimize space charge non-linearities) Implementation of new optimized lay-out for an integrated photo-injectorImplementation of new optimized lay-out for an integrated photo-injector (proper phase tuning of emittance oscillations for max. brightness) Produce RF bunch compression with Emittance PreservationProduce RF bunch compression with Emittance Preservation (increasing peak current at no expense of transverse emittance)

Laser pulse length: 9ps FWHM Emittance measurements for gaussian and square laser pulse shapes Courtesy of F. Sakai Achieving Record Sumitomo SHI + FESTA

L Laser Pulse Shaping Techniques Collinear Acousto-Optic modulator (AOM) z TeO 2 DAZZLER Liquid Crystal Phase Mask

LINAC Working Point - Emittance

Slice analysis through the bunch

RF Deflector: principle of operation

Slice SPARC using a slit and RF Deflector, with and without clipping SPARC Review - Sept. 23rd 2003 Bunch head Bunch tail Z(m) 300  m Coupling of time-transverse coordinate with 1:1 c.c.

Brightness is crucial for many Applications SASE FEL’s Plasma Accelerators Relativistic Thomson Monochromatic X-Ray Sources Courtesy of D. Umstadter, Univ. of Michigan

Collaborations and UE programs SPARC DESY BNL UCLA SLAC UE MOU UE EUROFEL PITZ MOU

FERMI A VUV - FEL user facility at nm SPARX An R&D program for a X-ray FEL test facility Next steps in Italy: Next steps in Italy: (only half of the original budget available from the Research Ministry to support two programs) (only half of the original budget available from the Research Ministry to support two programs)

SPARX- test facility upgrade the DAFNE Linac to drive a 5-10 nm SASE-FEL and with seeding Beam energy : GeV upgrade the injector to a RF photo-injector (SPARC-like) Study group will prepare a proposal within 2005

SPARC Injector + DA  NE Linac SPARX-ino a 5-10 nm SASE FEL source at LNF RF gun Linac 1 IV PC E=.44 GeVE=.145 GeV f= -25° Linac 2 s z ~ 210 mm s z ~ 50÷80 mm s d < 1 E-3 E= 1.25 GeV R 56 = 34 mm

Low Energy section RF gun

High energy section E tot ~ 1.5 GeV w 4 sections (3GHz)E tot ~ 1.8 GeV w 2 sections (11.4 GHz)E tot ~ 2.1 GeV w 3 sections (11.4 GHz)E tot ~ 1.2 GeV dogleg start

Time to conclude…  FELs are opening new scenarios in many branches of science  No FELs possible without the skills of the accelerator physicists  No FEL useful without a robust R&D in innovative instrumentation  Exciting possibilities to be investigated also in fundamental science