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Capri, 3 Giugno 2003
Esperimenti con fasci di elettroni brillanti per la fase 2 di SPARC Luca Serafini - INFN / Milano • High Brightness e- Beams & TW Power Photon Beams : Applications for SPARC-II • Velocity Bunching (CORA) : production of ultra-short bunches • Ultra-High Gradient Acceleration : a 2nd generation Plasma Acceleration experiment • A Source of Mono-chromatic X-Rays for advanced clinical diagnostics Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Transverse Brightness of Electron Beams Bn 2I nx ny A m2 rad 2 I = peak current nx = rms normalized transverse emittance Quality Factor : beam peak current density normalized to the rms beam divergence angle (linked to transverse beam coherence) Round Beam : nx = ny , J = I /s2 s nb s s’low s’s/b b 2J 2Js 2 Bn 2 2 s n z x’ s’high x seq Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Brightness is crucial for many Applications Lg 32 K Bn 1 K 2 2 SASE FEL’s Courtesy of D. Umstadter, Univ. of Michigan n p 50 m n p p p 30 100 m n p 2 Plasma Accelerators NX T f N N h e nb * ; b sz * Relativistic Thomson Monochromatic X-Ray Sources Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Three Generations of Electron Sources • Thermo-Ionic time-scale Qbunch=1-100 nC Bn=1010 A/(m.rad)2 s ns (ps with RF bunchers) I=0.1 10 A DC Diode (triode) with thermoionic cathode E ≈10 MV/m • Photo-Injectors time-scale Bn=1015 A/(m.rad)2 ps 100 A RF Cavity with photo-cathode MV/m • Plasma Guns time-scale Bn =1014-1015 A/(m.rad)2 fs Langmuir waves in cold plasmas + local wave-breaking Capri, 3 Giugno 2003 Qbunch=0.1-10 nC I=10 E ≈50-150 Qbunch=1-10 pC I≈ 1 kA E ≈ 1-10 GV/m “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Achieved Brightness in RF Photo-Injectors TTF photo-inj. (achieved) 6.1012 exit of linac (compr.) 2.1013 ATF photo-inj. (achieved) 5.1013 @ photocathode 1.2.1015 Max. achievable without compr. n-cath =thermal LCLS (requested @ 15 GeV) 4.1015 nx =ny=1.5 m Bn 2I nx ny I = bunch peak current ESRF (storage ring) < 1014 nx =20 m ny=0.07 m SPARC ultimate goal (Ph. 2) 2.1015 Capri, 3 Giugno 2003 A m2 rad 2 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Wide International Community on High Brightness Beams THE PHYSICS OF HIGH BRIGHTNESS BEAMS Proc. of the 2nd ICFA Advanced Accelerator Workshop University of California, Los Angeles, Nov. 1999 edited by James Rosenzweig & Luca Serafini Web page: www.physics.ucla.edu/AABD Per vedere questa immagine occorre QuickTime™ e un decompressore GIF. Physics and Science with the X-ray Free-Electron Laser (Arcidosso, Italy, September 10-15, 2000) C. Pellegrini and M. Cornacchia Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Velocity Bunching: integrated compression in photoinjectors Courtesy of D. Yeremian, SLAC Slow wave structure Standard v=c structure r 27 ; b r 0.9993 1000 100 800 80 Compression during acceleration I [A] Current scaling with energy 400 60 40 200 20 I/ = const. 0 0 0 Capri, 3 Giugno 2003 2 4 6 Z [ m] 8 10 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” T [MeV] 600 Trapped trajectories in a slow wave: the Hamiltonian model @ a≈ 1 • If the phase velocity of the wave is ~c k k0 k r c k k0 ck ; br 1 2k 2ck H br 2 1 a cos 4a r2 kz t 0 eE0 a 2 mc k Phase space plot s for a slow wave with resonant gamma r 12 and a 0.2 Top of the separatrix at max 4a 2r Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” A quarter synchrotron oscillation gives phase compression • By Injecting at r and extracting at 0 we perform an energy spread enhancement associated to a phase spread reduction Beam run off-crest ‘chirps’ and compresses rf wave Courtesy of S. Anderson Zoom-in of the diagram plot ted in previous transp. corresponding to 20 . Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” z =1 .5 z =3 0 -1.5 -1 -0.5 0 0 .5 1 1 .5 2 -1.5 -1 -0.5 0 0 .5 1 1 .5 1 Bu nc hi n g 0 -2 Dz [m m] z =1 0 1 Bu nc hi n g 0 -2 z =4 .5 1 Bu nc hi n g Bu nc hi n g 1 Bu nc hi n g z =0 .3 1 0 2 -2 -1.5 -1 -0.5 Dz [m m] 0 0 .5 1 1 .5 2 0 -2 -1.5 -1 -0.5 Dz [m m] 0 0 .5 1 1 .5 2 -2 -1.5 -1 -0.5 Dz [m m] 0 0 .5 1 1 .5 2 Dz [m m] 3 rms norm. emittance [um] 2.5 beam current [kA] 2 LCLS Photoinjector with RF Compression 1.5 1 0.5 Gun Linac 0 0 2 4 6 3 solenoids for additional focusing z =0 .3 z =1 .5 1 00 Z_[m] z =3 1 00 0 8 10 2 solenoids for additional focusing z =4 .5 3 00 0 z =1 0 6 00 0 6 00 0 4 00 0 4 00 0 2 00 0 50 5 00 -50 0 -50 0 DE _[Ke V] 0 DE _[Ke V] DE _[Ke V] DE _[Ke V] DE _[Ke V] 1 00 0 0 2 00 0 2 00 0 0 0 -20 00 -20 00 -10 00 -10 0 -10 00 -20 00 Capri, 3 Giugno 2003 -15 0 -15 00 -2 -1.5 -1 -0.5 0 DZ_[mm ] 0 .5 1 1 .5 2 -2 -1.5 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” -30 00 -1 -0.5 0 DZ_[mm ] 0 .5 1 1 .5 2 -40 00 -2 -1.5 -1 -0.5 0 DZ_[mm ] 0 .5 1 1 .5 2 -2 -1.5 -1 -0.5 0 DZ_[mm ] 0 .5 1 1 .5 2 -40 00 -2 -1.5 -1 -0.5 0 DZ_[mm ] 0 .5 1 1 .5 2 First PARMELA Simulation of RF Compressor C. Ronsivalle Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” RF Compression at DUVFEL P. Piot et al., PRSTAB 6 (2003) 033503 undulators linac (off) 75 MeV dump Capri, 3 Giugno 2003 dump linac 75 MeV 5 MeV DUVFEL “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Initial Velocity Compression Measurements at Livermore/Pleiades Autocorrelation Signal (normalized) Compressed Beam Pulse Length Measurement 1.2 1 0.8 0.6 inj 85 0.4 s < 0.3 psec t 0.2 0 0 5 10 15 20 Delay Arm Position (psec) Courtesy of S. Anderson / LLNL Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Preliminary Results Consistent with Simulation Simulated Pulse Length Vs Injection Phase 3 HOMDYN Simulation Measurement 2.5 E CTR 1.5 7º FWHM t s (psec) 2 1 0.5 0 -100 -80 -60 -40 -20 0 20 40 Phase wrt Peak Acceleration (degrees) Courtesy of S. Anderson / LLNL Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Q2 st I SPARC - Phase 2 X band structure RF-Gun RF compressor SLAC structure SLAC structure Longitudinal emittance compensation via 4th harmonic decelerating section (B. Spataro) Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Performances @ full compression I T Longitudinal phase space distribution s taken at different tim es throughout the compressor for the case of total compression. Beam current (solid lin e, left scale, in A) and energy evolution (dashed lin e, righ t scale, in MeV) through a 500 MeV Linac with impl ementation of a RF rectilin ear compressor and a 3rd harmoni c corrector. Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Performances @ full compression 40 2 35 1.5 I z 25 . mm] 30 1 15 10 / 20 n sr 0.5 / 5 0 0 0 5 10 15 20 25 z [m] Energy spread in % (dotted line, right scale) and longitud inal emitt ance in keV.mm (solid l ine, left scale) Capri, 3 Giugno 2003 Rms beam envelope in mm (dotted lin e, left scale) , rms normalized transverse emittance in mm.mrad (solid l ine, right scale) and beam peak current in A (solid l ine, right scale) along the Lin ac. The r.h.s. diagram shows the details of the upp er one along th e first 3 m of RF gun, drift, 3rd harmonic structure (from z=1.2 to z=1.28) and RF compressor (from z=1.4 to z=4.4) “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Application to SPARX (M. Ferrario) Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” SPARC Building Complex Bunker open for implementation of future beam experiments with additional beam lines Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” SPARC-I Laser layout 10 nJ 800 nm IR 10 ps flat-top 266 nm UV Larger Laser Pulse Energy needed for TW Photon Beams Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Upgrade of SPARC Laser to TW Power Level: third stage of amplification to reach 0.5-1 J energy per pulse ( P > 10 TW ) Mode-locked femtosecond Ti:sapphire oscillator 10 Hz, SH, 1 J Flashlamp pumped Nd:YAG laser Stretcher To the Compressor FR IRIS IRIS BD IRIS IRIS 73゜ Courtesy of F. Sakai Capri, 3 Giugno 2003 Regenerative Amplifier 5-pass master Amplifier “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Pulse Stretcher Oscillator Multi-Pass Amplifier Regenerative Amplifier Pulse Compressor under vacuum Courtesy of F. Sakai Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Two additional beam lines at SPARC for plasma acceleration and monochromatic X-ray beams 100 fs synchr. Ti:Sa multi-TW Laser System 1 J, 10 ps gaus 20 mJ, 10 ps flat top 500 J Compr.1 2 nC, 10 ps* J, 100 fs gaus 20 pC, 20 fs$ *n=2 m, s=50 m 1 nC, 10 ps, n=1 m Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” $ n=0.2 m, s=10 m All Optical Injectors (Plasma Guns) vs External Injection L.I.L.AC scheme, D. Umstadter Plasma wavelength 10-100 m Local Wave-Breaking induced by second (synchronized!) laser pulse Captures background plasma electrons locally into the accelerating bucket (D. Giulietti) <R> [mm] enx [mmmrad] Tfin = 360 MeV 20 fs, 1 kA, 6% en. spread 20 1.5 15 1 10 0.5 5 0 0 0 0.1 0.2 0.3 0.4 Z [m] Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” enx [mmmrad] External Injection in SPARC HOMDYN (M.Ferrario) <R> [mm] 2 p = 300 m sp= 100 m Eacc = 3 GV/m Compact Sources of Monochromatic X-rays based on Relativistic Thomson back-scattering X las / 42((1-cosY)/2) las = 0.8 m =80 (40 MeV) X =0.32 Å, 37 keV NX T f N N h e 2 s coll T 710 29 m2 N X 2 10 9 /11 f 10Hz, N _ 1010 , Nh 1018 , s coll 50, 5m e Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Non-invasive Coronaric Angiography Dynamic IVCAG (Intravenous Coronary Arteriography) using monochromatic X-rays produced by Synchrotron Radiation and monochromators was clinically tested at KEK-AR and Tsukuba University, obtaining clear dynamic images (33 shots/s) of the coronary artery, with 37 keV X-rays , 1011 photons/s generated by an undulator at the AR ring (intravenous contrast agent applied). Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Mammography with Mono-chromatic X-Rays Mammography images of adenoca rcinoma. (a) conventional mammogr.; (b) monochromatic beam at 22.2 keV; (c) phase con trasst image; (d) histological section. The con strast (sens iti vit y to tis sue density variations ) goe s from 8% to 0.1%, whil e the spatial r esolution go es from 0,15 -0,3 mm to 0.01-0.015 mm. This means the capabilit y to detect a tumor 30 tim es small er in volume, i.e. a 2 yea r earli er detection o f the tumor. Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Experiments world-wide on ComptonBackscattering for Monochromantic X-rays Sumitomo-Festa (S-band, medical) Univ. of Tokyo - NERL (S-band, medical) NIRS - Univ. of Tokyo - KEK (X-band, medical) SLAC (X-band, medical) Brookhaven ATF (S-band, by-product in laser acceleration) Livermore (S-band, material studies, nuclear weapons) Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Sumitomo - Festa Collab. (Tokyo) Measured spatial profile of the scattered X-rays (The electron beam is in the plane of the laser polarization) X Y 70mm (B) **The lines represent the results of the theoretic analysis** Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Spectral Distributions Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” CONCLUSIONS • SPARC is aimed at delivering within 3 years a top brightness electron beam (Ph. 1) • Velocity Bunching will ultimately allow to reach unprecedented quality beams in a compact system (200 MeV) • SPARC has the chance to become an advanced facility in the international scenario to conduct frontier beam physics (High Gradient Acceleration and Advanced X-ray Beams) Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Innovative Concepts / Components in SPARC • Use of Shaped Laser Pulses (minimize space charge non-linearities) • Implementation of Ferrario Working Point in an optimized integrated photoinjector (proper phase tuning of emittance oscillations) • Applying Velocity Bunching with Emittance Preservation (increasing peak current at no expense of transverse emittance) Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” NEW CONCEPTS Velocity Bunching in Photoinjectors RF Compression during Acceleration • Rectilinear Compression (no Coherent Synch. Radiation effects) based on longitudinal focusing in slow RF waves • Alternative option of bunch compression high brightness sub-ps beams (as needed by X-Ray SASE Fel’s) • Performed at low energy (10-80 MeV), fully integrated into the emittance correction process (for maximum brightness) LS and M. Ferrario, AIP 581 (2001) 87 Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” From Thermoionic Injectors to Laser-Driven RF Photo-Injectors : the Quest for Beam Brightness Thermoionic Injectors operate in a quasi-steady state regime at low DC field amplitudes - the beam has to be manipulated by bunchers to get down to the ps time scale - this causes a severe emittance grow Integration of emission process into the bunching action of RF accelerating field RF Photo-Injectors Hera Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Emittance and brightness scaling n 1 mm.mrad 0.8 S-band 0.6 L-band 0.4 0.2 X-band 0.2 0.4 0.6 0.8 Q Bn 1.2 1 1.2 [nC] 1400 1200 S-band 1000 A/mm2mrad2 1 800 600 400 200 0 Capri, 3 Giugno 2003 L-band 0.2 0.4 0.6 0.8 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Q [nC] Achieving Uniform Bunch Distributions using Flat-Top Laser Pulses @ Sumitomo SHI + FESTA Temporal distributions of shaped UV laser pulses by a X-ray streak camera Gaussian pulse shape Square pulse shape The flatness of square-shaped laser pulse: 5~25% @ 4~14 ps FWHM The fluctuation of shaped pulse length: 7% (pulse-to-pulse)@both shapes Capri, 3 Giugno 2003 Courtesy of F. Sakai “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Achieving Record Emittances @ Sumitomo SHI + FESTA Emittance measurements for gaussian and square laser pulse shapes Laser pulse length: 9ps FWHM Courtesy of F. Sakai Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Thermoionic Injectors LIMITATIONS Cathode Emissivity J < 20 A/cm2 1 nC over 20 ps scat > 9 mm Diode Saturation Child-Langmuir Law I = kV3/2 V=100 kV I=15 A with k=5.10-7 Field limited MATURE and CONSOLIDATED TECHNOLOGY Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Radio-Frequency Photo-Injectors LIMITATIONS Transverse plasma oscillations UCLA/SLAC/BNL S-band next gen. RF Gun Time dependent space charge effects dilution of projected emittance Photocathode and/or laser disuniform. h Space charge field non-linearities dilution of slice emittance Temperature emittance @ photocath. Mature but non Consolidated Technology Stability , repetibility , ease of tuning Capri, 3 Giugno 2003 PROBLEMS Space and Time Jitters Laser beam quality Challenging Diagnostics (sub-ps) “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Plasma Guns: simulations results* (ongoing exp. @ LBL and Univ. of Michigan) very sensitive to injection phase particle momentum vs. time Q=10 pC st=20 fs sE=5% n=5 m Bn=1.5.1013 - Brightness comparable to RF Photo-Injectors - fs bunches fully sinchronized to the laser - unproven technology - beam physics (in plasma) still to be explored * T. Katsouleas et al., PRE 57 (1998) 5920 Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Non-invasive Coronaric Angiography 1 2 Boone JM, Seibert JA. A Figure of Merit Comparis on between Brems strahlung and Monoen ergetic X-ray Sources for Ang iogr aphy. Journal of X-ray Science and Techno logy . 4:334-345, 1994. Carroll FE, Waters JW, Price RR, Brau CA, Roos CF, Tolk NH, Pickens DR, Stephens WH. Nearmonochro matic x-ray beams produced by the free electron laser and Co mpton ba ckscatter. Inves t Radiol 25:465 -471, 1990. "Monochromatic X Rays are capab le of delivering the same immage quality at about half the radiation dose to the patient compared to conventional x rays tubes" Corona ric Angiog raphy canno t be app li ed nowaday s as a mass screening diagnos tics because of the h igh mortalit y ris k associa ted wit h the intra-artery catheter insertion: it is considered a high risk (0.23% mortalit y, 2.2% patie nt damage ) inv asive diagnos tics. Mono -chromatic X-ray based non-inv asive diagnos tics would all ow a population preven tive screening of coronar ic stenos is, whic h is responsible for most of cardiovascular diseases, that in turn represent the highe st cause of mortalit y in western coun tries. Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Experimental Results(Phase-I) A ps electron beam Energy: 14 MeV Bunch charge: 0.5 nC Pulse length: 3 ps(rms) Focused beam size: 100 m(rms) Pointing stability: 6 m (rms) Time jitter: 1.4ps (rms) between e- bunch and fs laser pulse A fs laser beam Wavelength: Pulse energy: Pulse length: Focused beam size: Capri, 3 Giugno 2003 800nm 85mJ/pulse 100fs(rms) 20m@90o-collision 108m@0o-collision A X-ray beam With the 0o-collision X-ray energy: Pulse length (calc.): Intensity: Intensity fluctuation: 4.6keV(peak) 3ps(rms), 1.5x105/pulse 10% With the 90o-collision X-ray energy: Pulse length (calc.): Intensity: Intensity fluctuation: 2.3keV(peak) 270fs(rms), 1.4x104/pulse 25% “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Next Steps in Sumitomo-Festa Experiment The spatial profile of a 270fs-long X-ray pulse with a peak energy of 2.3keV was measured in 90o Compton scattering as a function of the laser polarization, and compared with the theoretical analysis. The number of X-ray photons generated was obtained to be 1.4x104/pulse. The stability of the X-ray intensity was measured to be 25%(rms). Experimental Plan(Phase-II): High-energy X-rays: >30keV increasing the accelerated electron energy: >40MeV High-intensity X-rays: >1010photons/s Multi-bunch electron generation 1J femtosecond laser with multi-collision High-stability X-rays: A precise optical timing synchronization Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Sumitomo - Festa Collab. (Tokyo) RF Timing Synchronizer TW Ti:Sapphire Laser Remote Controlled Mirror Photocathode RF Gun Compton Chamber Linac X-ray Detectors Beam Dump 8m Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” TW femtosecond Ti:Sapphire laser 3.6m x 1.5m BD PM IRIS Pulse Compressor G1 IRIS 23° 37° 56. 95° BD PM IRIS 73゜ Compton chamber IRIS FR BD BD [Main Specifications] pulse energy 100 mJ pulse width 100 fs focused beam size 50 m pointing stability ±5 rad pulse repetition rate 10 Hz Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” 1Terawatt Ti:sapphire laser system Mode-locked femtosecond Ti:sapphire oscillator 10 Hz, SH, 1 J Flashlamp pumped Nd:YAG laser Stretcher To the Compressor FR IRIS IRIS BD IRIS IRIS 73゜ Regenerative Amplifier Capri, 3 Giugno 2003 5-pass master Amplifier “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Linearity of X-ray Intensity vs. Laser Energy Stability of X-ray Intensity 25% (rms) within 10 min. **The results observed in 90o collision** Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” X-ray Imaging Measurement Window Optical Lens ( f=100mm ) X-rays ICCD Camera （Gate time: 10ns） MCP Capri, 3 Giugno 2003 Phosphor Screen (10ns,410nm) “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” 90-degree laser-Compton scatterings between a relativistic electron beam and a linear-polarized laser beam Laser photons electrons Laser photons electrons Scattered X-rays Scattered X-rays (A) (B) (A)the electron beam is in the plane of the laser polarization. (B)the electron beam is perpendicular to the plane of the laser polarization. Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Anticipated Performances of Univ. of Tokyo - NERL experiment Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Pulse Stretcher Multi-pass Amplifier Regenerative Oscilla tor Amplifier Pulse Compressor Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” X-band advanced protoype Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ” Capri, 3 Giugno 2003 “ Fisica e Tecnologia degli Acceleratori e Tecniche Correlate ”