Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS II J. B. Hastings, SLAC/SSRL February 23, 2003 · · · Overview Scientific Opportunities LCLS II Scope · · · Short pulses Multiple undulators Photon energies > 8 ke. V · Cost and schedule · Summary BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Overview LCLS will provide A single undulator that can provide radiation from 800 e. V to 8 ke. V Baseline pulses of 230 fs Simultaneous use of several end stations possible with xray splitting techniques Science case is strong for the baseline facility First operations will define Areas of significant scientific payoff XFEL operation and performance 0. 8 -8 ke. V (15 -1. 5 Å) User demand BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Overview cont’d Unique SLAC infrastructure enables expansion of LCLS into LCLS II Expertise in electron accelerators The SLAC Linac Space BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center SLAC Linear Collider Linac Coherent Light Source Center Stanford Linear Accelerator Linac begin, 50 Ge. V electron and 1989: Two SLCMile operations 1992: Proposal (C. Pellegrini) Final Focus Beam Facility SPEAR 3. 7 Ge. V Storage Ring and Synchrotron Radiation • Electron/positron accelerators positron beams Test achieved 1998: Preliminary Design Study test of essential features of. Completed the NLC • 1962: Synchrotron radiation Start of accelerator construction • Power-pulse compression using SLAC Energy 1999: R&D funded at $1. 5 M/year 1972: SPEARof operations begin • In service scientific excellence Doubler (SLED) 2001: CD-0 1973: Stanford Synchrotron Radiation Project (SSRP) started – First Light 1989: Construction Complete 1967: 20 -Ge. V beamwith achieved • Strong and electron fruitful ties Stanford University 2002: Conceptual Design http: //www-ssrl. slac. stanford. edu/lcls/CDR/ 1977: SSRP becomes Stanford Synchrotron Production and control of 70 begins nanometerto. Radiation beams Laboratory (SSRL) • The first linear collider – a commitment 2003: Project Engineering Design 1990: SPEAR II - a dedicated synchrotron radiation facility the long-range of high begin energy electron 2005: Long-Leadfuture 2003: SPEARProcurements III Commissioning machines 2006: Construction begins 2007: First Light 1998: First colliding beams 2008: Project completion BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center chicane located after PEP-II extraction ‘RTL’ 9 Ge. V e- pulsed extraction 3 Ge. V e+ pulsed extraction ‘scavenger’ bunch (e+ production) passes through chicane Routine interleaving of multiple energy beams on a pulse by pulse basis BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center The SLAC Linac as an FEL Driver LCLS 4. 5 -14. 3 Ge. V Possibilities 120 Hz. 50 Ge. V beam energy Pulse to pulse energy variation at 120 Hz. Small steps for FEL wavelength tunability Large steps for multi-wavelength multi-undulator operations 300 ns macro pulse with up to 32 micro pulses BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Science Opportunities Shorter pulses Imaging of single particles =>avoid radiation damage Evolution of structural changes resolved on atomic scale Chemical dynamics: observation of atomic motions and electronic structure on the femtosecond timescale Multiple undulators provide multi-wavelength operations Spectroscopic studies of both atomic and electronic structures Increased user capacity Higher photon energies E ~ 30 -40 ke. V Access to the K or L edges of all elements above carbon in the periodic table Higher resolution in structural studies: disordered systems, liquids BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Pump-probe studies Diffraction methods Provide atomic scale resolution in disordered systems Anomalous scattering can ‘isolate’ atoms of interest Spectroscopic tools can probe the time evolution of the electronic and atomic structures: critical in understanding chemical reactions on surfaces (catalysis) and in liquids Photon in-photon out: overcome space charge issues in electron spectroscopies. Inelastic x-ray scattering permits the investigation of both surfaces and bulk systems in a wide variety of sample environments. BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Neutze et al. , Phs. Rev. Lett. 87, 195508 (2001) I 2 in CH 2 Cl 2 scattering angle =60º at 8 ke. V K edge 33. 2 ke. V Typical intensity: 1011 photons per time step BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Single particle imaging J. Hajdu et al. LCLS First Experiments Calculated scattering pattern from lysozyme molecule Lysozyme Coherent diffraction from a gold nanocrystal I. K. Robinson et. al. , Phys. Rev. Lett. 87, 195505 -1 (2001) BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Linac Coherent Light Source single bunch, 1 -n. C, 120 -Hz 7 Me. V z 0. 83 mm 0. 2 % w ne Linac-1 L =9 m rf = -38° 21 -1 b 21 -1 d . . . existing linac DL-1 L =12 m R 56 0 z 0. 022 mm 0. 76 % X Linac-2 L =330 m rf = -43° Linac-3 L =550 m rf = -10° 21 -3 b 24 -6 d 25 -1 a 30 -8 c BC-1 L =6 m R 56= -36 mm SLAC linac tunnel Energy reach, multi-user BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II 4. 54 Ge. V z 0. 19 mm 1. 8 % 14. 35 Ge. V z 0. 022 mm 0. 02 % Linac-X L =0. 6 m rf=180 rf gun Linac-0 L =6 m 250 Me. V 150 Me. V z 0. 83 mm 0. 10 % Feb 23, 2003 BC-2 L =22 m R 56= -22 mm undulator L =120 m DL-2 L =66 m R 56 = 0 FFTB hall Photon energy, longitudinal phase space (pulse length), multi-users Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center How to Produce Short Pulses: to 10 fs and below Chirp the electron beam Produce a chirped photon beam: use a monochromator to ‘slice’ a small time portion of the beam in energy => a short pulse in time Compress the chirped photon beam : preserve the intensity. How? an R&D Issue ‘Cut’ the electron beam Use wakefields in the undulator vacuum chamber …. . BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Short pulses: Chirped pulse slicing Electron bypass Monochromator FEL Amplifier SASE FEL Energy 1 st Undulator chirped electron beam Frequencychirped radiation 2 nd Undulator Input radiation DE/E 10 -3 Pulse Slicing BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu Output radiation

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Wakefields in the Undulator Vacuum Channel A method for ‘cutting’ the electron bunch After S. Reiche, UCLA This requires TAPERING the undulator BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS with Multiple Beamlines FFTB m-shielding 330 m 535 m 62 m 100 m Note: Design Hall A and Hall B compatible with LCLS II Expansion BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Full use of the SLAC Linac Increase photon energy Varied pulse formats BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center SLAC commitment Statement from the SLAC Director “The LCLS and its expansion are critical ingredients in the broad scientific portfolio of the SLAC site for the coming decades. I encourage the LCLS team to consider the unique possibilities that the full capabilities and flexibility of the SLAC linac, including electron beams up to 50 Ge. V, will offer. Further, I encourage them to integrate these possibilities into the plans for the expansion of LCLS beyond its baseline operating parameters. ” “SLAC and its talented staff of accelerator physicists and engineers routinely operate the linac in a multi-user mode with high operational efficiency. For example, the linac currently serves to inject the B-factory in parallel with fixed target high energy physics experiments and accelerator R&D. We expect that such operational flexibility will enable the linac, with suitable modifications, to serve the needs of an expanded LCLS well into the future. ” BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Higher photon energies For a given wiggler: r 1/ 2 To increase energy (shorter wavelength) at the fundamental: Increase the electron energy. Electron Energy (Ge. V) Photon Energy (ke. V) Photon Wavelength (Å) 15 9. 0 1. 37 18 13. 1 0. 95 21 17. 7 0. 70 26 26. 9 0. 46 BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Higher Photon Energies Quantum fluctuations limit FEL performance Performance for LCLS Baseline 1. 2 mm-mrad emittance (26. 9 ke. V) (17. 7 ke. V) (13. 1 ke. V) (9. 0 ke. V) BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center (~1. 5 mm realistic goal) e. N < 1 mm at 1 Ǻ, 15 Ge. V transverse emittance: radiation wavelength peak current undulator period energy spread: <0. 08% at Ipk = 4 k. A, K 4, lu 3 cm, … beta function undulator ‘field’ FEL gain length: 20 Lg > 100 m for e. N 1. 5 mm Need to increase peak current, preserve emittance, and maintain small energy spread, all simultaneously BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Reduce gun emittance =>Increase parameter (100 ke. V) BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Adjust the undulator period, emittance: 0. 3 mm-mrad BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center 0. 3 mm mrad 103 ke. V 44 ke. V 5 k. A BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Elements of LCLS II With gun performance of 0. 3 mm-mrad the facility will span with FEL radiation 250 e. V to 45 ke. V using FULL energy of the SLAC Linac 8 Independent undulators each with a different electron energy running at 15 hz (120 hz with pulse trains at single energy) Pulse lengths variable from 10 -100 fs The ultimate goal: Transform limited sub-femtosecond pulses in the Å regime BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Technical risks Short wavelengths: gun performance Multiple undulators: CSR effects Short pulses: Solutions to get to 1 fs These risks will be addressed during commissioning and early operations of LCLS and by significant R&D during the LCLS construction and early ops phases. Early operations will define the science case for LCLS II BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center R&D requirements Build and commission LCLS on schedule Gain operational experience Define the scientific opportunities Gun emittance: push to 0. 3 mm-mrad or below and/or increase peak current Develop an x-ray optics tool kit to permit manipulation of the spatial and temporal coherence BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Costs (based on LCLS CDR in FY 02 dollars) For One undulator Undulator systems XR-Transport, Optics, Diagnostics (20%) Endstation systems $50. 0 M (30%) $26. 6 M $10. 0 M (30%) LCLS second linac/injector system Injector Linac Modifications $20. 4 M (30%) $23. 1 M (30%) Expanded Experiment Hall Conventional Facilities excluding added tunneling $12. 0 M Infrastructure $10. 0 M (contingency shown for LCLS, Linac elements could be considerably higher for LCLS II) BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Schedule: A phased approach based on: Science driven opportunities Advances in accelerator technology Install second undulator and experimental end station: 2012 Install second injector full energy operation (up to 50 Ge. V) if science opportunity requires and technology warrants: 2012 Install additional undulators/beamlines BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 2014 -2016 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu

Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Summary LCLS II is a critical part of the vision for science on the SLAC site The flexibility and energy reach of the SLAC S-band linac make it an ideal FEL driver foreseeable future LCLS II will build on the investments in the LCLS II can be phased consistent with scientific demand advances in accelerator R&D BESAC Subcommittee on BES 20 yr Facilities Roadmap LCLS II Feb 23, 2003 Jerome Hastings, SLAC/SSRL jbh@slac. stanford. edu