A Free Electron Laser Project at LNF Massimo Ferrario INFN - LNF & the SPARC/X Team

1. A Free Electron Laser Project at LNF Massimo Ferrario INFN - LNF & the SPARC/X Team

2. Outline Atomic Laser Synchrotron Radiation Free Electron Laser (FEL) SPARC - SPARXINO - SPARX Applications

3. Atomic Laser Light Amplification by Stimulated Emission of Radiation Spontaneous Emission Stimulated Emission

4. Properties of Stimulated Emission The photon which is emitted in the stimulated emission process is identical to the incoming photon. They both have: 1. Identical wavelengths - Monochromaticity. 2. Identical directions in space - Directionality. 3. Identical phase - Coherence.

6. Atomic Laser 1. Well known and proven technology. 2. One Laser One Color. 3. Limited by Mirrors ==> No X rays.

7. Cosmic MASER

8. Synchrotron Radiation

9. Charged particle moving on a circle Radiation Simulator – T. Shintake, @ http://www-xfel.spring8.or.jp/Index.htm

10. Pulse Duration

11. Revolution Frequency N Cut-Off Frequency of the Spectrum

13. Undulator Radiation

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

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

16. Radiation Simulator – T. Shintake, @ http://www-xfel.spring8.or.jp/Index.htm

17. Nu = 5 { { { { { 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

18. Spectral Intensity Line width

19. Peak power of accelerated charge: different electrons radiate indepedently hence the total power depends linearly on the number Ne of electrons per bunch: Incoherent Spontaneous Radiation Power: Coherent Stimulated Radiation Power: WE NEED micro-BUNCHING !

21. High Gain FEL Consider“seeding”by an external light source with wavelength r The light wave is co-propagating with the relativistic electron beam Energy exchangeoccurs only if there is transverse motion

22. After one wiggler period the electron sees the radiation with the same phase if the flight time delay is exactly one radiation period: In a resonant and randomly phased electron beam, nearly one half electrons absorb energy and half lose enrgy, with no net gain The particles bunch around a phase for which there is no coupling with the radiation

23. NewtonLorentz Equations t>0 l /2 t=0 Maxwell Equations Optical potential Question: can there be a continuous energy transfer from electron beam to light wave? Answer: We need a Self Consistent Treatment

24. The electron beam acts as a dielectric medium which slows down the phase velocity of the ponderomotive field compared to the average electron longitudinal velocity. Hence resonant electrons bunch around a phase corresponding to gain. The particles within a micro-bunch radiate coherently. The resulting strong radiationfield enhances the micro-bunching even further. Result: collective instability, exponential growth of radiation power. Even if there is no external seeding: Self Amplified Spontaneous Emission

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

26. TTF FEL LEUTLE

27. Slippage length  independent processes ζ SASE Longitudinal coherence The radiation “slips” over the electrons for a distanceNurad

28. SASE Courtesy L. Giannessi (Perseo in 1D mode http://www.perseo.enea.it)

30. SEEDING Courtesy L. Giannessi (Perseo in 1D mode http://www.perseo.enea.it)

33. High Brightness Electron Beams

34. Linear Accelerators PRINCIPIO: Le particelle emesse da un filamento vengono accelerate dal campo elettrico longitudinale generato da elettrodi susseguenti.

35. Campo elettrico fascio Linear Radio-Frequency Accelerators

36. Electron Photo-Injector

37. SPARC - SPARXINO - SPARX

39. GENESIS simulation of the SPARC SASE-FEL Radiation power growth along the undulator @ 530 nm

40. BNL DESY EUROFEL UE SPARC UCLA MOU MOU SLAC

42. I = 1 kA K = 3 e = 0.1 % n=4 cr [nm] n=1 Energy [GeV] SPARC Injector + DAFNE Linac SPARXINO a <10 nm SASE FEL source at LNF

43. The FEL Applications

44. 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 • Short Pulses

45. Free Electron Lasers: applicazioni diminuire la lunghezza d’onda (λ-> raggi X) Impulsi ultra-corti aumentare potenza media (per λ nell’ IR-UV) Applicazioni mediche e industriali Struttura della materia,ad es. Dinamica delle molecole, reazioni chimiche

46. E. Muybridge at L. Stanford in 1878 disagree whether all feet leave the ground during gallop… E. Muybridge used spark photography to freeze this ‘ultra-fast’ process E. Muybridge, Animals in Motion, ed. L. S. Brown (Dover Pub. Co., New York 1957) Courtesy Paul Emma (SLAC).

48. Coulomb Explosion of Lysozyme (50 fs) Single Molecule Imaging with Intense X-rays Atomic and molecular dynamics occur at the fsec-scale J. Hajdu, Uppsala U.

49. LCLS at SLAC 1.5-15 Å X-FEL based on last 1-km of existing SLAC linac

50. user facility TESLA XFEL at DESY 0.85-60 Å multiple undulators X-FEL Integrated into linear collider