L O A Victor Malka LOA, ENSTA – CNRS - École Polytechnique, Palaiseau cedex, France COULOMB05, Senagolia, Italy, September (2005) State of Art of Laser-Plasma Accelerators Laser beam Electron beam 1 mm Laser beam proton beam 1  m

L O A Particle group F. Ewald J. Faure Y. Glinec A. Lifschitz J.J. Santos Laser group F. Burgy B. Mercier J.Ph. Rousseau A.Pukhov, University of Dusseldorf, Germany ELF SPL Collaborators E. Lefebvre, CEA/DAM Ile-de-France, France Supported by EEC under FP6 : CARE

L O A E-field max ≈ few 10 MeV /meter (Breakdown) R>R min Synchrotron radiation Classical accelerator limitations LEP at CERN 27 km Circle road 31 km New medium : the plasma Energy = Length = $$$ ≈ PARIS

L O A Why is a Plasma useful ? Plasma is an Ionized Medium High Electric Fields epz nE~~ w Superconducting RF-Cavities : E z = 55 MV/m ez nE~ Are Relativistic Plasma waves efficient ? E z = 0.3 GV/m for 1 % Density Perturbation at cc -1 E z = 300 GV/m for 100 % Density Perturbation at cc -1

L O A Tajima&Dawson, PRL79 How to excite Relativistic Plasma waves ? The laser wake field  laser ≈ T p / 2 = >Short laser pulse Laser pulse F≈-grad I Electron density perturbation Phase velocity v  epw =v g laser => close to c Analogy with a boat

L O A F≈-grad I Train of short resonant pulses Laser envelop modulation    k     k 2 How to excite Relativistic Plasma waves? (ii) The laser beat waves  1 -  2 =  p Linear growth : d(t)=1/4a 1 a 2 w p t =>Homogenous plasmas Saturation : relativistic, ion motion Optical demonstration by Thomson scattering : Clayton et al. PRL 1985,Amiranoff et al. PRL 1992,, Dangor et al. Phys. Scrypta 1990 Chen, Introduction to plasma physics and controlled fusion, 2 nd Edition, Vol.1, (1984) Motivations

L O A electron Analogy: t 1 t 2 t 3  e >>   >> 1 => E max (MeV)=(  n/n)(n c /n e ) =>L deph. =(=( 0 /2)(n c /n e ) 3/2 E max =2(  n/n)   2 mc 2 L Deph. = p   2 Analogy electron/surfer Motivations

L O A Motivations

L O A Few MeV gain Laser Injected electrons Few MeV Injected electrons acceleration with laser : Wake field, Beat wave Motivations

L O A Electron Acceleration : LBWF Electron spectra indicate an E field of ≈ 0.7 GV/m   = 100,  e = 6,  laser = 40 µm,  e = 40 µm, divergence = 10 mrad Electrons number experiment ,33,43,53,63,73,83,9 Theory Energy (MeV) d = 1,6% LULI/LPNHE/LPGP/LSI/IC Electron gain demonstration Few MeV’s: Kitagawa et al. PRL 1992,Clayton et al. PRL 1993,N. A. Ebrahim et al., J. Appl. Phys.1994, Amiranoff et al. PRL 1995 Motivations

L O A How to generate an electron beam? Self-modulated Laser Wakefield Scheme (Andreev, Sprangle, Mora 1992) c  p enhances Wavebreaking P c (GW) = 17  0 2 /  p 2 Short Pulse Energetic Electrons if then excites Modena et al., Nature 1995

L O A Wave breaking : from waves to particles

L O A. Relativistic wave breaking Electrons/MeV detector limit Energy (MeV) n e =0.5x10 19 cm -3 n e =1.5x10 19 cm -3

L O A Review of some Former Experiments on LabYear ProcessE L Rate E e RAL1995* SMLWF50 J 20 min 44 MeV 1998 SMLWF 50 J 20 min 100 MeV NRL1997 SMLWF 5 J 5 min 30 MeV MPQ1999 DLA 0.2 J 10 Hz 10 MeV LOA 1999 SMLWF 0.6 J 10 Hz 70 MeV LOA2001 FLWF 1 J 10 Hz200 MeV Electron Beam Generation Large scale, energetic laser, with low repetition rate

L O A 5-pass Amp. : 200 mJ 8-pass pre-Amp. : 2 mJ Oscillator : 2 nJ, 15 fs Stretcher : 500 pJ, 400 ps After Compression : 1 J, 30 fs, 0.8  m, 10 Hz, m Nd:YAG : 10 J 4-pass, Cryo. cooled Amp. : < 3.5 J, 400 ps Salle Jaune Laser

L O A E max (MeV) n e (cm -3 ) E max =4  p 2 m e c 2 dn n Tunable electron beam : temperature Electrons are accelerated by epw V. Malka et al., PoP (2001) F/6 INCREASE THE ACCELERATION LENGTH

L O A Interaction chamber (inside) Laser beam electron beam 50 cm

L O A Summary of FLWF previous results V. Malka et al., Science, 298, 1596 (2002) Energy (MeV) Detection Threshold Number of electron (/MeV/sr) Experiments

L O A

SMLWF : Multiple e - bunches / FLWF Single e - bunch Electron bunches laser Electric field Ps V. Malka, Europhysics news, April 2004 Ps/fs Electron bunch laser Electron density perturbation n e /n 0 -1 Electric field 0 fs

L O A Quasi-Monoenergetic Electron Beams In homogenous plasma : virtual or real? E, MeV t=350 t=450 t=550 t=650 t=750 t= N e / MeV Time evolution of electron spectrum monoenergetic electron beam VLPL A.Pukhov & J.Meyer-ter-Vehn, Appl. Phys. B, 74, p.355 (2002) One stage LPA

L O A Experimental Setup : single shot measurement

L O A 2.0 x cm -3 Divergence = 6 mrad Recent results on e-beam : Spatial quality improvements 6.0 x cm x cm x cm x cm x cm -3

L O A Recent results on e-beam : From Mono to maxwellian spectra Electron density scan V. Malka, et al., PoP 2005

L O A Charge in [ ] MeV : (500 ±200) pC Energy distribution improvements: The Bubble regime PIC Experiment Divergence = 6 mrad

L O A S. Mangles et al., C. Geddes et al., J. Faure et al., in Nature 30 septembre 2004

L O A Some Applications... X-rays:diffraction medicine  -rays:radiography Medicine Radiotherapy Proton-therapy PET Accelerator Physics Chemistry Radiolysis Electrons and Protons generated by Laser-Plasma Interactions + X ray Larmor X ray laser

L O A GeV acceleration in two-stages GeV Laser Plasma channel TW ~50 fs Nozzle Gas-Jet Laser 170±20 MeV 30 fs 10 mrad 1 J 10 TW 30 fs Pulse guiding condition : Δn>1/πr e r c 2 Weak nonlinear effects  more control : a 0 ~ 1-2 High quality beams : L b <λ p  n 0 <10 18 cm -3 rcrc ΔnΔn n0n0 Density profile

L O A GeV in low plasma density in plasma channel n 0 = cm -3, 11 J TW r c =40 μm, Δn=2 n 0 L channel =4 cm 8 cm 12 cm dN/dE(a.u.) Energy (MeV) Electron bunch Electric field Electron bunch Electric field

L O A On the ultra short duration benefit fs radiolysis : H 2 O (e - s, OH., H 2 O 2, H 3 O +, H 2, H. ) e-e- Very important for: Biology Ionising radiations effects B. Brozek-Pluska et al., Radiation and Chemistry, 72, (2005) **Ar.

L O A In collaboration with L. Le-Dain, S. Darbon from CEA Mourainvilier and DAM Material science:  -ray radiography High resolution radiography of dense object with a low divergence, point-like electron source Glinec et al., PRL 94 p (2005)

L O A  -radiography results A-A' cut 20mm Cut of the object in 3D Spherical hollow object in tungsten with sinusoidal structures etched on the inner part. Measured Calculated Source size estimation : 450 um

L O A Medical application : Radiotherapy VHE ELECTRONS

L O A Dose deposition profile in water Glinec et al., accepted in Med. Phys.

L O A Laser plasma acceleration has demonstrated Energy gains of 1 MeV to 200 MeV E-fields of 1 GV/m to 1000 GV/m Good e-beam quality : Emittance < 3  mm.mrad charge at high energy Quasi monoenergetic Very high peak current : 100 kA Laser plasma accelerators advantages Provide e-beam with new parameters : short Provide e-beam with new parameters : high current Provide e-beam with new parameters : Collimated Compact and low cost The laser plasma accelerators status ゝ ゝ ゝ ゝ ゝ ゝ ゝ ゝ ゝ ゝ

L O A Laser plasma accelerator: enhance stability electron sources up to ≈ 1 GeV (nC, <1 ps): Guiding or PW class laser systems Single Stage (Pukhov, Mori) (200TW) Generate a tunable e-beam applications of these electron sources Compact XFEL Perspectives

L O A A revolution is coming…one of the most evolving field in Science, a wonderful tool for academic formation