linac coherent light source update john n galayda 22 july 2002 n.
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Linac Coherent Light Source Update John N. Galayda 22 July 2002

Linac Coherent Light Source Update John N. Galayda 22 July 2002

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Linac Coherent Light Source Update John N. Galayda 22 July 2002

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  1. Linac Coherent Light Source UpdateJohn N. Galayda22 July 2002 • Project scope • Cost estimate • DOE Review 23-25 April - results • Future John N. Galayda

  2. LINAC COHERENT LIGHT SOURCE I-280 Sand Hill Rd John N. Galayda

  3. N S N S N S N N S N S N S N S N N N N S S S S N N N N S S S S N N N N S S S S N N N N S S S S N N N N N N N S S S S S S S N N N N N N N S S S S S S S N N N N N N N S S S S S S S N N N N N N N S S S S S S S S N S N S N S N S N S N S N S N S N S N S N S The LCLS produces extraordinarily bright pulses of synchrotron radiation in a process called “self-amplified spontaneous emission” (SASE). In this process, an intense and highly collimated electron beam travels through an undulator magnet. The alternating north and south poles of the magnet force the electron beam to travel on an approximately sinusoidal trajectory, emitting synchrotron radiation as it goes. The electron beam and its synchrotron radiation are so intense that the electron motion is modified by the electric and magnetic fields of its own emitted synchrotron light. Under the influence of both the undulator magnet and its own synchrotron radiation, the electron beam is forced to form micro-bunches, separated by a distance equal to the wavelength of the emitted radiation. These micro-bunches begin to radiate as if they were single particles with immense charge. Since they are regularly spaced, the radiation from the micro-bunches has enhanced temporal coherence. This is indicated by the “smoothing out” of the instantaneous synchrotron radiation power (shown in the three plots to the right) as the SASE process develops. Saturation Exponential Gain Regime Undulator Regime Undulator Magnet Coherent Synchrotron Radiation Electron Bunch John N. Galayda

  4. Selected LCLS Baseline Design Parameters Fundamental FEL Radiation Wavelength 1.5 15 Å Electron Beam Energy 14.3 4.5 GeV Normalized RMS Slice Emittance 1.2 1.2 mm-mrad Peak Current 3.4 3.4 kA Bunch/Pulse Length (FWHM) 230 230 fs Relative Slice Energy Spread @ Entrance <0.01 0.025 % Saturation Length 87 25 m FEL Fundamental Saturation Power @ Exit 8 17 GW FEL Photons per Pulse 1.1 29 1012 Peak Brightness @ Undulator Exit 0.8 0.06 1033 * Transverse Coherence Full Full RMS Slice X-Ray Bandwidth 0.06 0.24 % RMS Projected X-Ray Bandwidth 0.13 0.47 % * photons/sec/mm2/mrad2/ 0.1%-BW John N. Galayda

  5. UCLA LLNL LCLS R&D Collaboration FEL Theory, FEL Experiments, Accelerator R&D, Gun Development, Undulator R&D John N. Galayda

  6. LCLS R&D, Preconceptual Design Organization John N. Galayda

  7. UCLA LLNL LCLS Project Engineering Design Organization John N. Galayda

  8. Project Description • Electron Beam Handling Systems • 1.2.1 Injector • Photocathode gun and drive laser • 150 MeV linac • Located in Sector 20 off-axis injector spur John N. Galayda

  9. Project Description • 1.2.2 Linac • X-band RF • Bunch Compressor 1, 250 MeV • Superconducting wiggler • Bunch Compressor 2, 4.5 GeV • Reconfiguration of transport to Final Focus Test Beam Area 7 MeV rf gun Linac-X L =0.6 m Linac-3 L =550 m new Linac-1 L =9 m Linac-2 L =330 m Linac-0 L =6 m 14.35 GeV undulator L =120 m 21-1b 21-1d 21-3b 24-6d 25-1a 30-8c X ...existing linac BC-1 L =6 m BC-2 L =22 m DL-1 L =12 m DL-2 L =66 m 150 MeV 250 MeV 4.54 GeV SLAC linac tunnel John N. Galayda

  10. x versus z without SC-wiggler 230 fsec projected emittance growth is simply ‘steering’ of bunch head and tail 0.5 mm x versus zwith SC-wiggler ‘slice’ emittance is not altered CSR Micro-bunching and Projected Emittance Growth 14.3 GeV at undulator entrance Workshop in Berlin, Jan. 2002 to benchmark results ( – follow-up meeting 1-5 July, Sardinia John N. Galayda

  11. Project Description • 1.2.3 Undulator Systems • 121 meter undulator channel, housed in extended FFTB • Diagnostics for x-ray beam and electron beam • Additional 30 meters of space for future enhancements (seeding, slicing, harmonics) 421 187 3420 UNDULATOR 11055 mm Beam Position Monitor Horizontal Steering Coil Quadrupoles X-Ray Diagnostics Vertical Steering Coil John N. Galayda

  12. Magnetic Measurement of the Prototype Horizontal Trajectory Microns John N. Galayda

  13. Project Description • 1.3 Photon Beam Handling Systems • 1.3.1 X-ray Transport, Optics and Diagnostics • Front end systems – attenuators, shutters, primary diagnostics • Optics – the prerequisites for LCLS experiments • Grazing incidence mirror to suppress 3rd harmonic • KB pair, refractive optics • Monochromators • Beam splitter • 1.3.2 X-ray endstation systems Hutches, Personnel Protection • Computer facilities for experiments • Laser for pump/probe experiments • Detectors matched to LCLS requirements Essential Infrastructure for the LCLS Experimental Program John N. Galayda

  14. LLNL X-ray Optics for the LCLS • Objectives • To transport the photon beam to diagnostics and optics stations • To provide the diagnostics necessary to characterize the photon beam • To provide the optics necessary to demonstrate the capability to process the photon beam • Requirements • Originally distilled by the working group from the ‘first experiments’ publication, and presentations John N. Galayda

  15. Optics Requirements • Focusing: Atomic physics, plasma physics, bio-imaging • 0.1-1 m over full energy range • Monochromatization: Plasma physics, materials science • Resolution of 10-3 - 10-5 at 8 keV • Harmonic control: Atomic physics, materials science • Ratio of higher harmonics to fundamental less than 10-6 • Photon pulse manipulation: Materials science • Split and delay over the range 1 ps to 500 ps John N. Galayda

  16. LLNL There are major technical challenges • General • Extreme fluences • maintaining optics for more than 1 pulse • Extremely small temporal and spatial characteristics • maintaining coherence during beam transport and manipulation • high resolution diagnostics • Parameters may vary pulse-to-pulse – need data on every pulse • Windowless operation required at 0.8 keV • Focusing, imaging, data acquisition, spectroscopy, etc. push state-of-the-art • To deal with the fluences, the following strategies are adopted • a far field experimental hall to reduce energy densities by natural divergence • a gas absorption cell and solid attenuator, to attenuate by up to 104 • low-Z optics that are damaged least • grazing incidence optics that increase the optical footprint and reflect most incident power John N. Galayda

  17. LLNL The fluence poses the primary challenge FEE Hall A Hall B • In Hall A, low-Z materials will accept even normal incidence. The fluences in Hall B are sufficiently low for standard optical solutions. Even in the Front End Enclosure (FEE), low Z materials may be possible at normal incidence above ~4 keV, and at all energies with grazing incidence. In the FEE, gas is required for attenuation at < 4 keV John N. Galayda

  18. LCLS Science Program based on the SSRL Model • Experiment Proposals will be developed by leading research teams with SSRL involvement • Proposals will be reviewed by the LCLS Scientific Advisory Committee • Research teams secure outside funding with SSRL participation and sponsorship as appropriate • SSRL will manage construction • Provides cost and schedule control, rationalized design • Provides basis for establishing maintenance and support infrastructure • SSRL will partner with research teams to commission endstations • “General user” mode with beam time allocation based on SAC recommendations John N. Galayda

  19. Project Description • 1.4 Conventional Facilities • Final Focus Test Beam Extension (30m beamline extension) • Hall A (30mx50m) • Hall B (35mx55m) John N. Galayda

  20. LCLS Cost Estimate • Costs collected at level 6 of the WBS • Labor in person-weeks • Labor type • Collaborating organization • Purchased materials and services • Assessment of Risk • Costs were collected in base year dollars (FY02) • Costs include: • Labor burden • Indirect costs • Contingency (listed separately) • Did not include inflation John N. Galayda

  21. Funding Profile John N. Galayda

  22. Costs by System John N. Galayda

  23. Costs by Collaborating Institution John N. Galayda

  24. Department of Energy Review 23-25 April 2002 • Review of Conceptual Design • • Prerequisite for Critical Decision 1, Approval of Preliminary Baseline Range • Charge to Committee • Is the conceptual design sound and likely to meet the technical performance requirements? • Are the project’s scope and specifications sufficiently defined to support preliminary cost and schedule estimates? • Are the cost and schedule estimates credible and realistic for this stage of the project? Do they include adequate contingency margins? • Is the project being managed(I.e., properly organized, adequately staffed) as needed to begin Title I design? • Are the ES&H aspects being properly addressed given the project’s current stage of development? John N. Galayda

  25. Department of Energy Review, 23-25 April 2002 • 17 reviewers, 6 DOE observers • 50 presentations by about 30 speakers • Reviewer Subpanels: • Accelerator Physics – Sam Krinsky, BNL • Injector/Linac – Richard Sheffield, LANL + George Neil, JLAB • Undulator – Kem Robinson, LBNL + Pascal Elleaume, ESRF • Photon Beam Systems – Steve Leone, U of CO + Dennis Mills, ANL • Controls Systems – Dave Gurd, ORNL • Conventional Facilities- Valerie Roberts, LLNL + Jim Lawson, ORNL • Cost/Schedule – John Dalzell, PNNL • Project Management – Jay Marx, LBNL+E. DeSaulnier + Ben Feinberg, LBNL • ES&H – Frank Kornegay, ORNL + Clarence Hickey, DOE/SC John N. Galayda

  26. Department of Energy Review, 23-25 April 2002 • CDR is superb • Cost estimate is credible • On track for approval of CD-1 Summer 2002 John N. Galayda

  27. Construction Strategy • 2003 – Project Engineering Design Begins • $6M budget • Prepare for Long-lead procurements in 2005 • Undulator • Gun Laser • Injector Linac Systems • Spring 2003 – review of plans for long lead procurements • CD-2A Go-ahead required • Spring 2004 – Complete Preliminary Design of LCLS • CD-2 requirements complete for entire project • October 2004 – begin long-lead procurements • Summer 2005 – Critical Decision 3 – Approve start of construction • Winter 2007 – Begin FEL commissioning • October 2008 – Project Complete John N. Galayda

  28. The Collaboration is ready to go- Gun Design Undulator Prototype Optics Fabrication Techniques Chicane for advanced accelerator R&D with ultrashort electron bunches Cost-effective magnet fabrication techniques developed for NLC John N. Galayda

  29. Upcoming Workshops • Planning Workshop for the LCLS Experiment Program • 7-8 October 2003, SSRL user meeting • Plan for early use of the LCLS • Define areas for R&D leading to experiment proposals • Kick off proposal preparation process John N. Galayda

  30. International X-FEL Collaboration Workshop • To be be scheduled late October • Define areas of common interest, collaborative activity • Short pulse diagnostic and experiment techniques • Optics • A natural sequence for LCLS/TESLA Collaboration • SLAC Sub-Picosecond Photon Source, 2003-2006 • TTF-II • LCLS • TESLA X-FEL • Other opportunities for US-Europe-Asia collaboration will be explored John N. Galayda

  31. News from DESY • DESY, TESLA • German Science Council Endorses TESLA • Very strong support of TESLA XFEL, Collider • Endorses physical separation of Collider and XFEL • http://WWW.WISSENSCHAFTSRAT.DE/presse/pm_2002.htm • Calls for Technical Design Report – faster-track, scaled-down XFEL • 5 undulators • 20 GeV linac • ~ € 530M (Materials & purchased services only, no overhead) • First use of a SASE FEL to do an atomic physics experiment • TESLA Test Facility, photoionization in xenon clusters • John N. Galayda

  32. End of Presentation John N. Galayda