J. Wu In collaboration with Y. Jiao, W.M. Fawley, J. Frisch, Z. Huang, H.-D. Nuhn, C. Pellegrini, S. Reiche (PSI), Y. Cai, A.W. Chao, Y. Ding, X. Huang,

Slides:



Advertisements
Similar presentations
Schemes for generation of attosecond pulses in X-ray FELs E.L. Saldin, E.A. Schneidmiller, M.V. Yurkov The potential for the development of XFEL beyond.
Advertisements

Soft X-ray Self-Seeding
Two-Color I-SASE A.Marinelli, J. Wu, C. Pellegrini LCLS2 Meeting SLAC 1/30/2013.
Workshop Issues Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Diagnostics.
1 Optimal focusing lattice for XFEL undulators: Numerical simulations Vitali Khachatryan, Artur Tarloyan CANDLE, DESY/MPY
Sub-femtosecond bunch length diagnostic ATF Users Meeting April 26, 2012 Gerard Andonian, A. Murokh, J. Rosenzweig, P. Musumeci, E. Hemsing, D. Xiang,
Approaches for the generation of femtosecond x-ray pulses Zhirong Huang (SLAC)
2004 CLEO/IQEC, San Francisco, May Optical properties of the output of a high-gain, self-amplified free- electron laser Yuelin Li Advanced Photon.
Hard X-ray FELs (Overview) Zhirong Huang March 6, 2012 FLS2012 Workshop, Jefferson Lab.
P. Emma LCLS FAC 12 Oct Comments from LCLS FAC Meeting (April 2004): J. Roßbach:“How do you detect weak FEL power when the.
P. Emma FAC Meeting 7 Apr Low-Charge LCLS Operating Point Including FEL Simulations P. Emma 1, W. Fawley 2, Z. Huang 1, C.
Performance Analysis Using Genesis 1.3 Sven Reiche LCLS Undulator Parameter Workshop Argonne National Laboratory 10/24/03.
A. Zholents, July 28, 2004 Timing Controls Using Enhanced SASE Technique *) A. Zholents or *) towards absolute synchronization between “visible” pump and.
1 Daniel Ratner 1 Gain Length and Taper August, 2009 FEL Gain length and Taper Measurements at LCLS D. Ratner A. Brachmann, F.J.
Z. Huang LCLS FAC April Effect of AC RW Wake on SASE - Analytical Treatment Z. Huang, G. Stupakov see SLAC-PUB-10863, to.
Overview of Proposed Parameter Changes Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator.
UCLA The X-ray Free-electron Laser: Exploring Matter at the angstrom- femtosecond Space and Time Scales C. Pellegrini UCLA/SLAC 2C. Pellegrini, August.
LCLS Transition to Science DOE Status Review of the LUSI MIE Project Near term opportunities for LCLS 'upgrades' J. Hastings for the LCLS Experimental.
W.S. Graves1 Seeding for Fully Coherent Beams William S. Graves MIT-Bates Presented at MIT x-ray laser user program review July 1, 2003.
A. Doyuran, L. DiMauro, W. Graves, R. Heese, E. D. Johnson, S. Krinsky, H. Loos, J.B. Murphy, G. Rakowsky, J. Rose, T. Shaftan, B. Sheehy, Y. Shen, J.
S2E in LCLS Linac M. Borland, Lyncean Technologies, P. Emma, C. Limborg, SLAC.
Free Electron Lasers (I)
S. Spampinati, J.Wu, T.Raubenhaimer Future light source March, 2012 Simulations for the HXRSS experiment with the 40 pC beam.
Soft X-ray Self-Seeding in LCLS-II J. Wu Jan. 13, 2010.
The Future of Photon Science and Free-Electron Lasers Ingolf Lindau Lund University and Stanford University MAX-Lab and Synchrotron Light Research KTH,
Beam Dynamics and FEL Simulations for FLASH Igor Zagorodnov and Martin Dohlus Beam Dynamics Meeting, DESY.
Optimization of Compact X-ray Free-electron Lasers Sven Reiche May 27 th 2011.
A bunch compressor design and several X-band FELs Yipeng Sun, ARD/SLAC , LCLS-II meeting.
LCLS-II Capabilities & Overview LCLS-II Science Opportunities Workshop Tor Raubenheimer February 10 th, 2015.
Max Cornacchia, SLAC LCLS Project Overview BESAC, Feb , 2001 LCLS Project Overview What is the LCLS ? Transition from 3 rd generation light sources.
X-Ray FEL Simulation: Beam Modeling William M. Fawley Center For Beam Physics Lawrence Berkeley National Laboratory ICFA 2003 Workshop.
External Seeding Approaches: S2E studies for LCLS-II Gregg Penn, LBNL CBP Erik Hemsing, SLAC August 7, 2014.
Basic Energy Sciences Advisory Committee MeetingLCLS February 26, 2001 J. Hastings Brookhaven National Laboratory LCLS Scientific Program X-Ray Laser Physics:
Harmonic lasing in the LCLS-II (a work in progress…) G. Marcus, et al. 03/11/2014.
Harmonic Lasing for LCLS-II? Z. Huang 11/10/
P. Krejcik LINAC 2004 – Lübeck, August 16-20, 2004 LCLS - Accelerator System Overview Patrick Krejcik on behalf of the LCLS.
NON-WIGGLER-AVERAGED START-TO-END SIMULATIONS OF HIGH-GAIN FREE- ELECTRON LASERS H.P. Freund Science Applications International Corp. McLean, Virginia.
Fluctuations Study Update A. Lutman. Model description Undulator section I 1D FEL code Bunch shape: flat top Short Bunch Long Bunch length20 fs50 fs current2.
The Next Generation Light Source Test Facility at Daresbury Jim Clarke ASTeC, STFC Daresbury Laboratory Ultra Bright Electron Sources Workshop, Daresbury,
Design Considerations of table-top FELs laser-plasma accelerators principal possibility of table-top FELs possible VUV and X-ray scenarios new experimental.
UCLA Claudio Pellegrini UCLA Department of Physics and Astronomy X-ray Free-electron Lasers Ultra-fast Dynamic Imaging of Matter II Ischia, Italy, 4/30-5/3/
Transverse Gradient Undulator and its applications to Plasma-Accelerator Based FELs Zhirong Huang (SLAC) Introduction TGU concept, theory, technology Soft.
LCLS-II: Accelerator Systems LCLS SAC Meeting P. Emma et al. April 23, 2010.
J. Wu March 06, 2012 ICFA-FLS 2012 Workshop Jefferson Lab, Newport News, VA Tolerances for Seeded Free Electron Lasers FEL and Beam Phys. Dept. (ARD/SLAC),
J. Corlett. June 16, 2006 A Future Light Source for LBNL Facility Vision and R&D plan John Corlett ALS Scientific Advisory Committee Meeting June 16, 2006.
E. Schneidmiller and M. Yurkov FEL Seminar, DESY April 26, 2016 Reverse undulator tapering for polarization control at X-ray FELs.
Harmonic lasing in the LCLSII SXR beamline G. Marcus, Y. Ding, Z. Huang 11/21/2013.
Applications of transverse deflecting cavities in x-ray free-electron lasers Yuantao Ding SLAC National Accelerator Laboratory7/18/2012.
LCLS-II options: CuRF → SXR, VPU, HXR harmonics G. Marcus 5/13/2015.
Some Simulations for the Proposed Hard X-Ray Self- Seeding on LCLS J. Wu J. Wu et al. Feb. 25, 2011.
E. Schneidmiller and M. Yurkov Harmonic Lasing Self-Seeded FEL FEL seminar, DESY Hamburg June 21, 2016.
Harmonic Generation in a Self-Seeded Soft X-Ray LCLS-II J. Wu Feb. 24, 2010.
SIMULATION FOR TW LCLS-II Tor’s question on the undulator length in the TW FEL senario SASE FEL undulator length 9, 10, and 11:  9 – m, 10.
Free Electron Laser Studies
Seeding in the presence of microbunching
Eduard Prat / Sven Reiche :: Paul Scherrer Institute
Beam dynamics for an X-band LINAC driving a 1 keV FEL
LCLS efforts: Self-seeding -- status report
Gu Qiang For the project team
Review of Application to SASE-FELs
Self-seeding for the soft x-ray line in LCLS upgrade
TW FEL “Death-Ray“ Studies
Z. Huang LCLS Lehman Review May 14, 2009
Two-bunch self-seeding for narrow-bandwidth hard x-ray FELs
SASE FEL PULSE DURATION ANALYSIS FROM SPECTRAL CORRELATION FUNCTION
Status of FEL Physics Research Worldwide  Claudio Pellegrini, UCLA April 23, 2002 Review of Basic FEL physical properties and definition of important.
Gain Computation Sven Reiche, UCLA April 24, 2002
LCLS FEL Parameters Heinz-Dieter Nuhn, SLAC / SSRL April 23, 2002
Achieving Required Peak Spectral Brightness Relative Performance for Four Undulator Technologies Neil Thompson WP5 – 20/03/19.
Introduction to Free Electron Lasers Zhirong Huang
Presentation transcript:

J. Wu In collaboration with Y. Jiao, W.M. Fawley, J. Frisch, Z. Huang, H.-D. Nuhn, C. Pellegrini, S. Reiche (PSI), Y. Cai, A.W. Chao, Y. Ding, X. Huang, A. Mandlekar, T.O. Raubenheimer, M. Rowen, S. Spampinati, J. Welch, G. Yu… LCLS-II Accelerator Physics meeting October 05, 2011 TW FEL simulations and uncertainties LCLS-II Accel. Phys., J. Wu, SLAC

LAYOUT A 1 Å Terawatts LCLS-II Simulation results for a TW LCLS-II 1.5 Å (8 keV), 1 Å (13 keV) Helical, Planar Start-to-end Uncertainties: jitter, error, fluctuation… LCLS-II Accel. Phys., J. Wu, SLAC

PREVIOUS PRESENTATIONS J. FEL R&D meeting, June 30, 2011 Y. LCLS-II Accelerator Physics meeting, July 27, 2011 J. FEL 2011 conference, August 24, 2011 W.M. Fawley, J. Frisch, Z. Huang, Y. Jiao, H.-D. Nuhn, C. Pellegrini, S. Reiche, J. Wu, paper submitted to proceedings of FEL 2011 conference, August 22—26, 2011 (also LCLS- TN-11-3; SLAC-PUB-14616). LCLS-II Accel. Phys., J. Wu, SLAC

A SASE FEL is characterized by the FEL parameter, ρ 1.the exponential growth, P = P 0 exp(z/L G ), where L G ~ λ U / 4πρ 2.The FEL saturation power P sat ~ ρ P beam SCALING For the LCLS-II electron beam: I pk ~ 4 k A, E ~ 14 GeV, P beam ~ 56 TW, FEL: ρ ~ 5 x 10 -4, P sat. ~ 30 GW << 1 TW 10 to 50 GW Overall, the peak power at saturation is in the range of 10 to 50 GW for X-ray FELs at saturation The number of coherent photons scales almost linearly with the pulse duration, and is ~10 12 at 100 fs, at 10 fs. LCLS-II Accel. Phys., J. Wu, SLAC

What happens when the FEL saturation is achieved Centroid energy loss and energy spread reaches ρ. Exponential growth is no longer possible, but how about coherent emission? Electron microbunching is fully developed As long as the microbunching can be preserved, coherent emission will further increase the FEL power Maintain resonance condition  tapering the undulator Coherent emission into a single FEL mode – more efficient with seeding scheme -- self-seeding Trapping the electrons BEYOND SATURATION LCLS-II Accel. Phys., J. Wu, SLAC

FIRST DEMONSTRATION OF TAPERING AT 30 GHZ* * T.J. Orzechowski et al. Phys. Rev. Lett. 57, 2172 (1986) The experiment was done at LLNL with a seeded, 10 cm wavelength FEL and a tapered undulator. LCLS-II Accel. Phys., J. Wu, SLAC

EXAMPLE OF TAPERING: LCLS W.M. Fawley, Z. Huang, K.-J. Kim, and N.A. Vinokurov W.M. Fawley, Z. Huang, K.-J. Kim, and N.A. Vinokurov, 483 Nucl. Instr. And Meth. A 483, 537 (2002) W.M. Fawley, Z. Huang, K.-J. Kim, and N.A. Vinokurov W.M. Fawley, Z. Huang, K.-J. Kim, and N.A. Vinokurov, 483 Nucl. Instr. And Meth. A 483, 537 (2002) LCLS 2 x Effect of tapering LCLS at 1.5 Å,1 nC, 3.4 kA. The saturation power at 70 m ~20 GW. A 200 m, un-tapered undulator doubles the power. Tapering for SASE FEL generates about 200 GW. A monochromatic, seeded, FEL brings the power to 380 GW, corresponding to 4 mJ in 10 fs (2 x photons at 8 keV). The undulator K changes by ~1.5 %. LCLS-II Accel. Phys., J. Wu, SLAC

OVERVIEW SASE FEL seeded FEL To overcome the random nature of a SASE FEL, which will set a limit to the final tapered FEL power, we study seeded FEL Producing such pulses from the proposed LCLS-II, employing a configuration beginning with a SASE amplifier, followed by a "self-seeding" crystal monochromator, and finishing with a long tapered undulator. TW-level feasible Results suggest that TW-level output power at 8 keV is feasible, with a total undulator length below 200 m including interruption. 40 pC 0.3-mm-mrad4 kA 14 GeV We use a 40 pC electron bunch charge, normalized transverse emittance of 0.3-mm-mrad, peak current of 4 kA, and electron energy about 14 GeV. LCLS-II Accel. Phys., J. Wu, SLAC

LCLS-II BASELINE UNDULATOR STRUCTURE Undulator section Undulator period u = 3.2 cm, Undulator length per section L u = 3.4 m, Number of the undulator periods NWIG = L u /  u = 106, Break length per section L b = 1 m Break length in unit of undulator periods NBREAK = L b /  u = 32. Filling factor = NWIG/(NWIG + NBREAK) = 77%. Break: Quad, BPM, phase shifter etc. LCLS-II Accel. Phys., J. Wu, SLAC

Genoli Start with a SASE FEL, followed by a self-seeding scheme (Genoli et al., 2010), and end up a tapered undulator SCHEME: WITHIN 200 M TOTAL LENGTH 1.3 TW Spectrum: close to transform limited e  chicane 1 st undulator 2 nd undulator with taper SASE FEL Self-seeded FEL e  dump eeee Single crystal: C(400) ~ 1 GW 30 m 160 m 4 m ~ 5 MW ~ 1 TW eeee LCLS-II Accel. Phys., J. Wu, SLAC

Resonant condition With the tapering model TAPERING PHYSICS AND MODEL (LONGITUDINAL PLANE) The order b is not necessarily an integer. Undulator parameter A w is function of z, after z 0, to maintain the resonant condition. LCLS-II Accel. Phys., J. Wu, SLAC

For the tapered undulator, before L sat, the exponential region, strong focusing, low beta function helps produce higher power (M. Xie’s formula). different After L sat, the radiation rms size increases along the tapered undulator due to less effectiveness of the optical guiding. The requirement is different. We empirically found that a variation in beta function instead of a constant beta function will help produce higher power. In most cases, optimal beta function will help extract up to 15% more energy even with optimal tapering parameters. The beta function is varied by linearly changing the quad gradient OPTIMAL BETA FUNCTION (TRANSVERSE, SECONDARY) The coefficient c can be positive or negative value. LCLS-II Accel. Phys., J. Wu, SLAC

8.3 keV Å (13.64 GeV) 40-pC charge; 4-kA peak current; 10 fs FWHM; 0.3-  m emittance Optimized tapering starts at 16 m with 13 % K decreasing from 16 m to 200 m, close to quadratic taper b ~ 2.03 Und. w = 3.2 cm, 3.4 m undulator each section, with 1 m break; average  x,y  = 20 m Longitudinal: close to transform limited 1.0 x 10  4 FWHMBW TW LCLS-II NOMINAL CASE 1.3 TW After self-seeding crystal LCLS-II Accel. Phys., J. Wu, SLAC

TW LCLS-II NOMINAL CASE 1.5 Å FEL at end of undulator (160 m) y (red); x (blue) x x y y E y (red); E x (blue) 5.0E+06 V/m ~ 80 % in fundamental Mode Transverse: M 2 ~ 1.3 LCLS-II Accel. Phys., J. Wu, SLAC

SIDE-BAND INSTABILITY, TAPERED FEL SATURATION Z. Huang and K.-J. Kim Even though the strong seed well dominates over the shot noise in the electron bunch, the long (160 m) undulator can still amplify the shot noise and excite side-band instability [Z. Huang and K.-J. Kim, Nucl. Instrum. Methods A 483, 504 (2002)]. the SASE component in the electron bunch and the residual enhanced SASE components in a self-seeding scheme can then couple and excite such a side-band instability, which together with other effects leads to the saturation as seen around 160 m LCLS-II Accel. Phys., J. Wu, SLAC

NOISE EXCITE SIDE-BAND INSTABILITY Spectrum 5 m With SASE(red); S-2-E(blue); LCLS-II Accel. Phys., J. Wu, SLAC

NOISE EXCITE SIDE-BAND INSTABILITY Spectrum 160 m With SASE(red); S-2-E(blue); LCLS-II Accel. Phys., J. Wu, SLAC

SATURATION OF TAPERED FEL Steady state (red), time-dependent with “natural” SASE (blue), and start-to-end (green) Steady state (red); With SASE (blue); S-2-E (green) Steady state (red); With SASE (blue); S-2-E (green) LCLS-II Accel. Phys., J. Wu, SLAC

START-TO-END BEAM Electron beam FEL temporal and 165 m LCLS-II Accel. Phys., J. Wu, SLAC

SENSITIVITY TO INPUT SEED POWER The seed power should be larger than a few MWs LCLS-II Accel. Phys., J. Wu, SLAC

STATISTICS OF A TW FEL POWER The statistical fluctuation increases, but not dramatically LCLS-II Accel. Phys., J. Wu, SLAC

SENSITIVITY TO UNDULATOR PARAMETER ERROR Red : Red : Maximum power with tapered undulator. Blue: Blue: Saturation power with untapered undulator. The maximum power of the tapered undulator is more sensitive to the undulator parameter errors than saturation power.  K /K = 0.01%, average power reduction ~15% Average power reduction ~ 3.5% 40 % 66 % 80 % 6 % 7 % 4 % LCLS-II Accel. Phys., J. Wu, SLAC

Shorten the system, higher FEL power Extend to 13 keV HELICAL UNDULATOR ENHANCE PERFORMANCE 8 keV 13 keV Second undulator Helical: (dashed) Planar: (solid) Helical: (dashed) Planar: (solid) LCLS-II Accel. Phys., J. Wu, SLAC

POWER VS. FILLING FACTOR (CHANGE NBREAK) time-independent Based on Genesis time-independent simulation. Normalized power = P / P(100% filling factor). LCLSII baseline, NWIG = 106, NBREAK = 32, Filling factor 77% P = 2.77 TW P norm = 0.57 Reduce break length, one can obtain larger filling factor and higher power. LCLSII baseline, NWIG = 106, NBREAK = 20, Filling factor 84% P = 3.45 TW P norm = 0.71 Increase ~ 25%. LCLS-II Accel. Phys., J. Wu, SLAC

A 1 – 1.5 Å TW FEL is feasible A 1 – 1.5 Å TW FEL is feasible High power, hundreds GW at 3rd harmonic, tens GW at 5 th harmonic, allowing to reach higher energy photon. High power, hundreds GW at 3rd harmonic, tens GW at 5 th harmonic, allowing to reach higher energy photon. This novel light source would open new science capabilities for coherent diffraction imaging and nonlinear science. This novel light source would open new science capabilities for coherent diffraction imaging and nonlinear science. ? Beyond 1 TW: helical undulator, high peak current, short interruption, fresh bunch… CONCLUSIONS LCLS-II Accel. Phys., J. Wu, SLAC