1. Workshop Issues Nuhn@slac.stanford.edu Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Diagnostics and Comm. Wrkshp, January 19-20, 2004 Heinz-Dieter Nuhn, SLAC / SSRL Workshop Issues Heinz-Dieter Nuhn, SLAC / SSRL January 19, 2004 Workshop Overview Discussion of the Commissioning Document Workshop Overview Discussion of the Commissioning Document

2. Workshop Issues Nuhn@slac.stanford.edu Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Diagnostics and Comm. Wrkshp, January 19-20, 2004 Heinz-Dieter Nuhn, SLAC / SSRL IntroductionIntroduction Undulator commissioning has been discussed over the last several years Many unsolved questions remain Main challenges are Radiation protection of magnetic material during commissioning and operation Development of detectors that can withstand the heat load Compilation of descriptions of detector types available for commissioning (both existing and under development) Electron detectors upstream of the undulators Electron and x-ray detectors along the undulator Electron and x-ray detectors after the undulator Decision on how to measure the FEL gain curve Simulation support: Enhancement of existing codes to Include simulation of X-ray diagnostics Undulator commissioning has been discussed over the last several years Many unsolved questions remain Main challenges are Radiation protection of magnetic material during commissioning and operation Development of detectors that can withstand the heat load Compilation of descriptions of detector types available for commissioning (both existing and under development) Electron detectors upstream of the undulators Electron and x-ray detectors along the undulator Electron and x-ray detectors after the undulator Decision on how to measure the FEL gain curve Simulation support: Enhancement of existing codes to Include simulation of X-ray diagnostics

3. Workshop Issues Nuhn@slac.stanford.edu Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Diagnostics and Comm. Wrkshp, January 19-20, 2004 Heinz-Dieter Nuhn, SLAC / SSRL Workshop Focus Commissioning of the Undulator Line of the LCLS with Beam Prerequisites Injector and Linac Commissioning Complete Undulator, Diagnostics, Shielding, Beam Dump etc. in Place Commissioning Without Beam for all Components Complete Main Commissioning Tasks Characterization of Electron Beam Up-Stream of Undulator Establishment of a Good Beam Trajectory Through Undulator to Beam-Dump Characterization of Spontaneous Radiation Establishment of SASE Gain Characterization of FEL Radiation Commissioning of the Undulator Line of the LCLS with Beam Prerequisites Injector and Linac Commissioning Complete Undulator, Diagnostics, Shielding, Beam Dump etc. in Place Commissioning Without Beam for all Components Complete Main Commissioning Tasks Characterization of Electron Beam Up-Stream of Undulator Establishment of a Good Beam Trajectory Through Undulator to Beam-Dump Characterization of Spontaneous Radiation Establishment of SASE Gain Characterization of FEL Radiation

4. Workshop Issues Nuhn@slac.stanford.edu Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Diagnostics and Comm. Wrkshp, January 19-20, 2004 Heinz-Dieter Nuhn, SLAC / SSRL GoalsGoals End-Of-Construction Goal Required by DOE to close-off construction project (CD-4) Needs to be simple to avoid project time and cost overrun Commissioning Goal Make LCLS ready for operation End-Of-Construction Goal Required by DOE to close-off construction project (CD-4) Needs to be simple to avoid project time and cost overrun Commissioning Goal Make LCLS ready for operation

5. Workshop Issues Nuhn@slac.stanford.edu Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Diagnostics and Comm. Wrkshp, January 19-20, 2004 Heinz-Dieter Nuhn, SLAC / SSRL Workshop Presentations Charge – J. Galayda Welcome – C. Pellegrini Workshop Issues – H.-D. Nuhn Status of Electron Beam Diagnostics – P. Krejcik Status of X-Ray Beam Diagnostics along the Undulator – S. Milton X-Ray Diagnostics after the Undulator – R. Bionta Electron Beam Control and Alignment – P. Emma Planning of FEL Simulations in Support of Commissioning Commissioning Simulations using GENESIS 1.3 – S. Reiche Commissioning Simulations using GINGER – W.M. Fawley Summary and Final Discussion – J. Galayda Charge – J. Galayda Welcome – C. Pellegrini Workshop Issues – H.-D. Nuhn Status of Electron Beam Diagnostics – P. Krejcik Status of X-Ray Beam Diagnostics along the Undulator – S. Milton X-Ray Diagnostics after the Undulator – R. Bionta Electron Beam Control and Alignment – P. Emma Planning of FEL Simulations in Support of Commissioning Commissioning Simulations using GENESIS 1.3 – S. Reiche Commissioning Simulations using GINGER – W.M. Fawley Summary and Final Discussion – J. Galayda

6. Workshop Issues Nuhn@slac.stanford.edu Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Diagnostics and Comm. Wrkshp, January 19-20, 2004 Heinz-Dieter Nuhn, SLAC / SSRL Expected Workshop Outcome Resulting Document: “Beam Commissioning of the LCLS Undulator System” LCLS Tech Note Target Date: Mid February 2004 Purpose Document Required for next DOE Review Basis for Starting R&D for Commissioning Diagnostics Resulting Document: “Beam Commissioning of the LCLS Undulator System” LCLS Tech Note Target Date: Mid February 2004 Purpose Document Required for next DOE Review Basis for Starting R&D for Commissioning Diagnostics

7. Workshop Issues Nuhn@slac.stanford.edu Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Diagnostics and Comm. Wrkshp, January 19-20, 2004 Heinz-Dieter Nuhn, SLAC / SSRL Draft Workshop Document Title: Beam Commissioning the LCLS Undulator Systems Acting Editor: James Welch Authors: R. Bionta, P. Emma, W. Fawley, Z. Huang, P. Krejcik, S. Milton, H.-D. Nuhn, C. Pellegrini, S. Reiche, J. Welch, ??? Available at Workshop WEB page. http://www-ssrl.slac.stanford.edu/lcls/undulator/meetings/2004- 01-19_diagnostics_comissioning/ http://www-ssrl.slac.stanford.edu/lcls/undulator/meetings/2004- 01-19_diagnostics_comissioning/ http://www-ssrl.slac.stanford.edu/lcls/undulator/meetings/2004- 01-19_diagnostics_comissioning/ Title: Beam Commissioning the LCLS Undulator Systems Acting Editor: James Welch Authors: R. Bionta, P. Emma, W. Fawley, Z. Huang, P. Krejcik, S. Milton, H.-D. Nuhn, C. Pellegrini, S. Reiche, J. Welch, ??? Available at Workshop WEB page. http://www-ssrl.slac.stanford.edu/lcls/undulator/meetings/2004- 01-19_diagnostics_comissioning/ http://www-ssrl.slac.stanford.edu/lcls/undulator/meetings/2004- 01-19_diagnostics_comissioning/ http://www-ssrl.slac.stanford.edu/lcls/undulator/meetings/2004- 01-19_diagnostics_comissioning/ Many Thanks !!!

8. Workshop Issues Nuhn@slac.stanford.edu Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Diagnostics and Comm. Wrkshp, January 19-20, 2004 Heinz-Dieter Nuhn, SLAC / SSRL Draft Document: Table of Contents 1. Introduction 2. Goal of Commissioning 3. Commissioning Procedure 4. Radiation Characteristics 5. Diagnostics 6. Troubleshooting A. Details: Electron Beam to Dump 1. Introduction 2. Goal of Commissioning 3. Commissioning Procedure 4. Radiation Characteristics 5. Diagnostics 6. Troubleshooting A. Details: Electron Beam to Dump

9. Workshop Issues Nuhn@slac.stanford.edu Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Diagnostics and Comm. Wrkshp, January 19-20, 2004 Heinz-Dieter Nuhn, SLAC / SSRL Draft Document: 3. Commissioning Procedure 3.1 Pre-Commissioning Status 3.2 Electron Beam to Dump 3.3 Beam-Based Alignment (BBA) 3.3.1 BBA Procedure 3.3.2 BBA Verification 3.4 Commission FEE Diagnostics 3.5 FEE Diagnostics Configuration 3.6 Commission Undulator Diagnostics 3.7 FEL Commissioning at Long Wavelength 3.7.1 Trajectory Distortion Method 3.7.2 Using Undulator x-ray Diagnostics 3.7.3 Independently Removable Segments 3.7.4 Variable Gap Undulator 3.1 Pre-Commissioning Status 3.2 Electron Beam to Dump 3.3 Beam-Based Alignment (BBA) 3.3.1 BBA Procedure 3.3.2 BBA Verification 3.4 Commission FEE Diagnostics 3.5 FEE Diagnostics Configuration 3.6 Commission Undulator Diagnostics 3.7 FEL Commissioning at Long Wavelength 3.7.1 Trajectory Distortion Method 3.7.2 Using Undulator x-ray Diagnostics 3.7.3 Independently Removable Segments 3.7.4 Variable Gap Undulator

10. Workshop Issues Nuhn@slac.stanford.edu Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Diagnostics and Comm. Wrkshp, January 19-20, 2004 Heinz-Dieter Nuhn, SLAC / SSRL Draft Document: 4. Radiation Characteristics 4.1 Along the Undulator 4.2 Downstream of the Undulator 4.2.1 FEL 4.2.2 Spontaneous 4.1 Along the Undulator 4.2 Downstream of the Undulator 4.2.1 FEL 4.2.2 Spontaneous

11. Workshop Issues Nuhn@slac.stanford.edu Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Diagnostics and Comm. Wrkshp, January 19-20, 2004 Heinz-Dieter Nuhn, SLAC / SSRL Draft Document: 5. Diagnostics 5.1 Undulator Diagnostics Instrumentation 5.2 Downstream X-Ray Diagnostics Intrumentation 5.2.1 Diagnostics in the FEE 5.2.2 Diagnostics in the Commissioning Diagnostics Tank 5.2.3 Total Energy 5.2.4 Pulse Length 5.2.5 Photon Spectrum 5.2.6 Transverse Coherence 5.2.7 Spatial Shape and Centroid Location 5.2.8 Divergence 5.1 Undulator Diagnostics Instrumentation 5.2 Downstream X-Ray Diagnostics Intrumentation 5.2.1 Diagnostics in the FEE 5.2.2 Diagnostics in the Commissioning Diagnostics Tank 5.2.3 Total Energy 5.2.4 Pulse Length 5.2.5 Photon Spectrum 5.2.6 Transverse Coherence 5.2.7 Spatial Shape and Centroid Location 5.2.8 Divergence

12. Workshop Issues Nuhn@slac.stanford.edu Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Diagnostics and Comm. Wrkshp, January 19-20, 2004 Heinz-Dieter Nuhn, SLAC / SSRL Related Document in Preparation Title: Undulator Protection Study Authors: E. Bong, P. Emma, P. Krejcik, H.-D. Nuhn, J. Welch Expected Completion: Early March 2004 Title: Undulator Protection Study Authors: E. Bong, P. Emma, P. Krejcik, H.-D. Nuhn, J. Welch Expected Completion: Early March 2004

13. Workshop Issues Nuhn@slac.stanford.edu Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Diagnostics and Comm. Wrkshp, January 19-20, 2004 Heinz-Dieter Nuhn, SLAC / SSRL Desirable measurement s as function of position along undulator : Intensity (LG, Saturation) Spectral Distribution Bunching Alternative measurements of saturation at undulator end: Intensity vs. Peak Current Intensity vs. Emittance Desirable measurement s as function of position along undulator : Intensity (LG, Saturation) Spectral Distribution Bunching Alternative measurements of saturation at undulator end: Intensity vs. Peak Current Intensity vs. Emittance FEL Gain Measurement Undulator Regime Exponential Gain Regime Saturation 1 % of X-Ray Pulse Electron Bunch Micro-Bunching

14. Workshop Issues Nuhn@slac.stanford.edu Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Diagnostics and Comm. Wrkshp, January 19-20, 2004 Heinz-Dieter Nuhn, SLAC / SSRL Measurement of SASE Gain along the undulator Direct: Put Detectors in the Breaks between Undulator Segments. No good solution for x-ray detector in existence, yet. Alternative: Characterize x-ray beam at single station down stream of undulator after gain is turned off at a selectable point along undulator by introduction of orbit distortion. (Initial studies by Z. Huang) removal of undulator segments (Changed Design) opening of gap if undulator is variable gap device. (Changed Design) Direct: Put Detectors in the Breaks between Undulator Segments. No good solution for x-ray detector in existence, yet. Alternative: Characterize x-ray beam at single station down stream of undulator after gain is turned off at a selectable point along undulator by introduction of orbit distortion. (Initial studies by Z. Huang) removal of undulator segments (Changed Design) opening of gap if undulator is variable gap device. (Changed Design)

15. Workshop Issues Nuhn@slac.stanford.edu Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Diagnostics and Comm. Wrkshp, January 19-20, 2004 Heinz-Dieter Nuhn, SLAC / SSRL Gain Measurement Scenarios (Reichanadter) Full Diagnostics Between Undulators Plusses: Allows Commissioning with all undulators in place Minuses: Does not Address Radiation Damage Issues. Most Expensive Option in Terms of $ and Resources Variable Gap Undulators Plusses: Addresses Radiation Damage Issue. Allows Commissioning with Single Suite of Diagnostics Downstream of the Undulator. Cost Neutral with respect to Full Diagnostics Minuses: Redesign of Undulator to Incorporate Variable Gap Function. Might Decouple Quads from Undulator. Translatable Undulators Plusses: Addresses Radiation Damage Issues. Allows Commissioning with Single Suite of Diagnostics Downstream of the Undulator. Much Cheaper. Minuses: Decouples Quads from Undulator. Movers more complicated but doable. Trajectory Distortion Plusses: Allows Commissioning with All Undulators in Place Minuses: Does not Address Radiation Damage Issues. Much Cheaper. Subject to Feasibility Study. Full Diagnostics Between Undulators Plusses: Allows Commissioning with all undulators in place Minuses: Does not Address Radiation Damage Issues. Most Expensive Option in Terms of $ and Resources Variable Gap Undulators Plusses: Addresses Radiation Damage Issue. Allows Commissioning with Single Suite of Diagnostics Downstream of the Undulator. Cost Neutral with respect to Full Diagnostics Minuses: Redesign of Undulator to Incorporate Variable Gap Function. Might Decouple Quads from Undulator. Translatable Undulators Plusses: Addresses Radiation Damage Issues. Allows Commissioning with Single Suite of Diagnostics Downstream of the Undulator. Much Cheaper. Minuses: Decouples Quads from Undulator. Movers more complicated but doable. Trajectory Distortion Plusses: Allows Commissioning with All Undulators in Place Minuses: Does not Address Radiation Damage Issues. Much Cheaper. Subject to Feasibility Study.

16. Workshop Issues Nuhn@slac.stanford.edu Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Diagnostics and Comm. Wrkshp, January 19-20, 2004 Heinz-Dieter Nuhn, SLAC / SSRL Commissioning Phases Phase 0: Beam Through Undulator (at 0.2 nC, sngl shot) Phase I: Spontaneous Radiation (at 0.2 nC, 10 Hz) Parameters: Energy 4.45-14.1 GeV, Emittance: not critical Goals: Establish straight and stable trajectory, measure spontaneous radiation Phase II: Low Energy FEL Radiation (at 0.2-1 nC, 10 Hz) Parameters:Energy: 4.45 GeV, Emittance: < 4 microns Peak Current : < 1 kA Goals: Characterize FEL radiation. Achieve saturation. Phase III: High Energy FEL Radiation (at 0.2-1 nC, 10 Hz) Parameters:Energy: >4.45 -14.1 GeV, Emittance: 1.2- 4 microns Peak Current : 1-3.4 kA Goals: Characterize FEL radiation, gain. Achieve saturation. Phase 0: Beam Through Undulator (at 0.2 nC, sngl shot) Phase I: Spontaneous Radiation (at 0.2 nC, 10 Hz) Parameters: Energy 4.45-14.1 GeV, Emittance: not critical Goals: Establish straight and stable trajectory, measure spontaneous radiation Phase II: Low Energy FEL Radiation (at 0.2-1 nC, 10 Hz) Parameters:Energy: 4.45 GeV, Emittance: < 4 microns Peak Current : < 1 kA Goals: Characterize FEL radiation. Achieve saturation. Phase III: High Energy FEL Radiation (at 0.2-1 nC, 10 Hz) Parameters:Energy: >4.45 -14.1 GeV, Emittance: 1.2- 4 microns Peak Current : 1-3.4 kA Goals: Characterize FEL radiation, gain. Achieve saturation.

17. Workshop Issues Nuhn@slac.stanford.edu Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Diagnostics and Comm. Wrkshp, January 19-20, 2004 Heinz-Dieter Nuhn, SLAC / SSRL ConclusionsConclusions Workshop Goal is to provide input to prepare a document describing the commissioning of the LCLS undulator with beam. Main Issues are: Definition of a Commissioning Procedure that provides Undulator Radiation Protection Selection of a Method for Measuring Radiation Properties along Undulator Multiple Detectors Positioned Along Undulator Gain Termination through Trajectory Distortion Removable Undulator Segments Variable Undulator Gaps Definition of R&D Program for Diagnostics Components Code Development to Support Commissioning Time is short – Quite a number of questions remains unanswered Workshop Goal is to provide input to prepare a document describing the commissioning of the LCLS undulator with beam. Main Issues are: Definition of a Commissioning Procedure that provides Undulator Radiation Protection Selection of a Method for Measuring Radiation Properties along Undulator Multiple Detectors Positioned Along Undulator Gain Termination through Trajectory Distortion Removable Undulator Segments Variable Undulator Gaps Definition of R&D Program for Diagnostics Components Code Development to Support Commissioning Time is short – Quite a number of questions remains unanswered

18. Workshop Issues Nuhn@slac.stanford.edu Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center Diagnostics and Comm. Wrkshp, January 19-20, 2004 Heinz-Dieter Nuhn, SLAC / SSRL End of Presentation