Yiping Feng LUSI DOE Review July 23, 2007 Diagnostics (WBS 1.5)1 Diagnostics (WBS 1.5) Yiping Feng Motivations System Specifications System Description WBS Schedule and Costs Summary Motivations System Specifications System Description WBS Schedule and Costs Summary

Yiping Feng LUSI DOE Review July 23, 2007 Diagnostics (WBS 1.5)2 Motivations X-ray Free-Electron Laser (FEL) is fundamentally different from storage-ring based synchrotron sources Linac-based, single-pass, 120 Hz at LCLS Feedback is limited by low repetition rate Each macro electron bunch is different in timing, length, density, energy (velocity), orbit, etc. X-ray amplification process based on self-seeding SASE* Lasing starts from a random electron density distribution Each X-ray pulse consists of a random time sequence of spikes of varying degrees of saturation  X-ray FEL exhibits inherent Intensity, spatial, temporal, and spectral fluctuations on pulse by pulse basis X-ray Free-Electron Laser (FEL) is fundamentally different from storage-ring based synchrotron sources Linac-based, single-pass, 120 Hz at LCLS Feedback is limited by low repetition rate Each macro electron bunch is different in timing, length, density, energy (velocity), orbit, etc. X-ray amplification process based on self-seeding SASE* Lasing starts from a random electron density distribution Each X-ray pulse consists of a random time sequence of spikes of varying degrees of saturation  X-ray FEL exhibits inherent Intensity, spatial, temporal, and spectral fluctuations on pulse by pulse basis *Self Amplification of Spontaneous Emission

Yiping Feng LUSI DOE Review July 23, 2007 Diagnostics (WBS 1.5)3 Goals X-ray diagnostics are required to measure these fluctuations since they can’t be eliminated Integral parts of Instruments Timing & intensity measurements for XPP experiments Wave-front characterization for CXI experiments Measurements made on pulse-by-pulse basis Requiring real-time processing by controls and data system Commonalities in needs & specs Standardized and used for all applicable instruments Modularized for greater flexibility of deployment and placement  Critical diagnostics must be performed and data made available on pulse-by-pulse basis X-ray diagnostics are required to measure these fluctuations since they can’t be eliminated Integral parts of Instruments Timing & intensity measurements for XPP experiments Wave-front characterization for CXI experiments Measurements made on pulse-by-pulse basis Requiring real-time processing by controls and data system Commonalities in needs & specs Standardized and used for all applicable instruments Modularized for greater flexibility of deployment and placement  Critical diagnostics must be performed and data made available on pulse-by-pulse basis

Yiping Feng LUSI DOE Review July 23, 2007 Diagnostics (WBS 1.5)4 Expected Fluctuations of LCLS FEL pulses ParameterValueOrigin* Pulse intensity fluctuation~ 30 % Varying # of FEL producing SASE spikes; 100% intensity fluctuation/per-spike; etc. Position & pointing jitter (x, y, ,  ) ~ 25 % of beam diameter ~ 25 % of beam divergence Varying trajectory per pulse; Saturation at different locations of  -tron curvature Source point jitter (z)~ 5 m SASE process reaching saturation at different z-points in undulator X-ray pulse timing (arrival time) jitter ~ 1 ps FWHM Timing jitter btw injection laser and RF; Varying e - energy per-pulse X-ray pulse width variation~ 15 % Varying e-energy leading to varying path (compression) in bunch compressors Center wavelength variation ~ 0.2 % (comparable to FEL bandwidth) Varying e-energy leading to varying FEL fundamental wavelength and higher order *To be discussed in details in breakout session

Yiping Feng LUSI DOE Review July 23, 2007 Diagnostics (WBS 1.5)5 X-ray Diagnostics Suite Fluctuation TypeDiagnostic Device Pulse intensity fluctuation a) Pop-In Intensity Monitor b) In-Situ BPM/Intensity Monitor Position & pointing jitter c) Pop-In Position/Profile Monitor In-Situ BPM/Intensity Monitor - Pointing determination from multiple BMP’s Source point jitter  Focal point jitter w/ focusing optics d) Wave-front Sensor - Back-propagating from radius of curvature measurement X-ray pulse timing jitter e) Electro-Optic Sampling (EOS) Device - Relative timing btw e-bunch & ref. probe laser X-ray pulse width variation EOS Device - Establishes upper limit Center wavelength variation LCLS e-energy calibration - X-ray wavelength cross-calibration is needed

Yiping Feng LUSI DOE Review July 23, 2007 Diagnostics (WBS 1.5)6 System Specifications Diagnostic ItemPurposesSpecifications* Pop-in intensity monitor (moderate-resolution) Coarse beam alignment/monitoring; Destructive; Retractable; Dynamic range 10 4 ; Per-pulse operation at 120 Hz; Relative accuracy < Pop-in position/profile monitor Coarse beam alignment/monitoring Destructive; Retractable; At 50  m resolution - 25x25 mm 2 field of view; At 10  m resolution - 5x5 mm 2 field of view In-situ Intensity monitor/BPM (high-resolution) Per-pulse normalization of experimental signals; High-resolution beam position monitoring Transmissive (< 5% loss); Dynamic range 10 6 ; Per-pulse operation at 120 Hz; Relative accuracy < In-situ Electro-optic sampling (EOS) device Measure relative timing between electron bunch (thus co- propagating x-ray pulse) and a probe optical laser pulse Non-intrusive to e-beam; Non-destructive; Per-pulse operation at 120 Hz; 20 fs resolution; In-situ Wave-front sensor Characterization of wave-front; Locating focal point of focused beam Destructive; Per-pulse operation at 120 Hz; 0.15 nm < < 0.3 nm * Must have high damage threshold Technically more challenging

Yiping Feng LUSI DOE Review July 23, 2007 Diagnostics (WBS 1.5)7 Pop-In Intensity Monitor (WBS 1.5.3) Coarse alignment of X-ray optics monochromators, mirrors, lens, etc. strategically placed in close proximity to optic Detection technique Pulse operation not photon counting Sensor type Si Diode (used successfully at SPPS) CVD Diamond Coarse alignment of X-ray optics monochromators, mirrors, lens, etc. strategically placed in close proximity to optic Detection technique Pulse operation not photon counting Sensor type Si Diode (used successfully at SPPS) CVD Diamond Destructive; Retractable; Moderate dynamic range 10 4 ; Relative accuracy < ; Per-pulse operation at 120 Hz; Si Diode stages FEL

Yiping Feng LUSI DOE Review July 23, 2007 Diagnostics (WBS 1.5)8 Pop-In Position/Profile Monitor (WBS 1.5.2) Destructive; Retractable; At 50  m resolution 25x25 mm 2 field of view; At 10  m resolution 5x5 mm 2 field of view; Coarse alignment of X-ray optics (beam finder) Optical imaging of fluorescence from a scintillating screen Positions in x, y 2D intensity profile Attenuation of beam may be required to avoid saturation Two modes of operation: low and high resolutions Coarse alignment of X-ray optics (beam finder) Optical imaging of fluorescence from a scintillating screen Positions in x, y 2D intensity profile Attenuation of beam may be required to avoid saturation Two modes of operation: low and high resolutions CCD Camera YAG Screen Mirror FEL stages

Yiping Feng LUSI DOE Review July 23, 2007 Diagnostics (WBS 1.5)9 In-Situ Intensity/Position Monitor (WBS 1.5.4) Transmissive (> 98% w/ 100  m 8 keV); High dynamic range 10 6 ; Relative accuracy < Position resolution < 5  m; Per-pulse operation at 120 Hz; Precise normalization of incident intensity to 0.1% Critical to XPP experiments where small change in diffraction intensity need to be resolved, i.e. Bi coherent phonon decay after photo-excitation Detection technique Compton back scattering from Be thin foil (up to 10 8 photons w/ in incident beam) Precise beam position calibration w/ use of array of sensors to < 5  m Commercial fluorescence monitor using similar design provides equal resolution but not viable due to damage considerations CVD diamond design more complex in fabrication Precise normalization of incident intensity to 0.1% Critical to XPP experiments where small change in diffraction intensity need to be resolved, i.e. Bi coherent phonon decay after photo-excitation Detection technique Compton back scattering from Be thin foil (up to 10 8 photons w/ in incident beam) Precise beam position calibration w/ use of array of sensors to < 5  m Commercial fluorescence monitor using similar design provides equal resolution but not viable due to damage considerations CVD diamond design more complex in fabrication Be thin foil FEL Quad- sensor

Yiping Feng LUSI DOE Review July 23, 2007 Diagnostics (WBS 1.5)10 Electro-Optic Sampling Device (WBS 1.5.6) Non-intrusive to e-beam; Non-destructive; Per-pulse operation at 120 Hz; Relative timing btw e-bunch & EOS-probe laser pulse  Inferring timing btw X-ray pulse & experimental probe laser Based on (linear) Pockels effect birefringence in strong E-field exerted by relativistic e-bunch in proximity 1-D Spatial encoding of timing for detection using CCD Single shot measurement EOS technique proven at SPPS 20 fs timing determination 200 fs resolution for e-bunch length Challenges Long distance btw EOS location (LTU) & experiments (NEH) 120 Hz operation requires real-time processing of EOS data Relative timing btw e-bunch & EOS-probe laser pulse  Inferring timing btw X-ray pulse & experimental probe laser Based on (linear) Pockels effect birefringence in strong E-field exerted by relativistic e-bunch in proximity 1-D Spatial encoding of timing for detection using CCD Single shot measurement EOS technique proven at SPPS 20 fs timing determination 200 fs resolution for e-bunch length Challenges Long distance btw EOS location (LTU) & experiments (NEH) 120 Hz operation requires real-time processing of EOS data EOS crystal Probe-laser footprint

Yiping Feng LUSI DOE Review July 23, 2007 Diagnostics (WBS 1.5)11 Hartmann Wave-front Sensor (WBS 1.5.5) Characterization of wave-front of focused X-ray FEL is a challenge Critical to CXI experiments if atomic resolution is ultimately to be achieved Common scanning or direct imaging techniques made at focus not viable due to FEL high peak power Hartmann Wave-front Sensor technique is viable Measurement made far from focus Focal point determination calculated from radius of curvature measurement Wave-front distortion obtained by back-propagation of diffracted wave-front determined at mask plane Commercial Hartmann wave-front for long wavelength Successful in optical applications (adaptive optics, etc.) For X-ray applications, X-EUV sensor for energy up to 4 keV Needs modification for higher energies and 120 Hz operation Characterization of wave-front of focused X-ray FEL is a challenge Critical to CXI experiments if atomic resolution is ultimately to be achieved Common scanning or direct imaging techniques made at focus not viable due to FEL high peak power Hartmann Wave-front Sensor technique is viable Measurement made far from focus Focal point determination calculated from radius of curvature measurement Wave-front distortion obtained by back-propagation of diffracted wave-front determined at mask plane Commercial Hartmann wave-front for long wavelength Successful in optical applications (adaptive optics, etc.) For X-ray applications, X-EUV sensor for energy up to 4 keV Needs modification for higher energies and 120 Hz operation

Yiping Feng LUSI DOE Review July 23, 2007 Diagnostics (WBS 1.5)12 Hartmann Wave-front Sensor (con’t) Image obtained from Imagine Optics, Ltd Challenges Working at 8 keV Tighter technical specs at shorter wavelength Mask must allow ray-optics approximation New 8 keV version being developed & tested now Mask materials must be compatible with FEL application 120 Hz operation will require customization Imaging sensor readout rate not sufficient Use pixelated detector capable of 120 Hz operation Integrate with Controls/Data systems Challenges Working at 8 keV Tighter technical specs at shorter wavelength Mask must allow ray-optics approximation New 8 keV version being developed & tested now Mask materials must be compatible with FEL application 120 Hz operation will require customization Imaging sensor readout rate not sufficient Use pixelated detector capable of 120 Hz operation Integrate with Controls/Data systems Algorithm Divergent wavefront

Yiping Feng LUSI DOE Review July 23, 2007 Diagnostics (WBS 1.5) WBS 1.5 Diagnostics Physics Support Eng. Integration Pop-in Position Monitor Engineering & 1 st article const XPP CXI XCS Pop-in Intensity Monitor Engineering & 1st article const XPP CXI XCS In-situ Intensity Monitor Engineering & 1st article const XPP CXI XCS In-situ Wave-front Sensor Engineering CXI In-situ EOS Device Engineering XPP

Yiping Feng LUSI DOE Review July 23, 2007 Diagnostics (WBS 1.5)14 Diagnostics Schedule in Primavera 3.1

Yiping Feng LUSI DOE Review July 23, 2007 Diagnostics (WBS 1.5)15 Diagnostics Milestones CD-1 Aug 01, 07 Conceptual Design Complete Oct 24, 07 CD-2a Dec 03, 07 CD-3a Jul 21, 08 Phase I Final Design Complete Oct 24, 07 EOS monitor complete Oct 20, 08 Pop-in position/profiler 1 st article Nov 25, 08 In-situ intensity/position 1 st article Jan 21, 09 Pop-in intensity 1 st article Apr 15, 09 Phase I Installation Complete Aug 21, 09 CD-4a Feb 08, 10 CD-1 Aug 01, 07 Conceptual Design Complete Oct 24, 07 CD-2a Dec 03, 07 CD-3a Jul 21, 08 Phase I Final Design Complete Oct 24, 07 EOS monitor complete Oct 20, 08 Pop-in position/profiler 1 st article Nov 25, 08 In-situ intensity/position 1 st article Jan 21, 09 Pop-in intensity 1 st article Apr 15, 09 Phase I Installation Complete Aug 21, 09 CD-4a Feb 08, 10

Yiping Feng LUSI DOE Review July 23, 2007 Diagnostics (WBS 1.5)16 Diagnostics Cost Estimate

Yiping Feng LUSI DOE Review July 23, 2007 Diagnostics (WBS 1.5)17 Summary Concepts of all diagnostic devices are well developed Frequent design discussions amongst LUSI and LCLS scientists EOS device was successfully deployed at SPPS 1 st articles will help LCLS commissioning/operation and early sciences on LUSI instruments LUSI EOS will aid LCLS e-beam diagnostics LUSI BPM could aid LCLS e-beam fast feedback system Ready to proceed with baseline cost and schedule development Concepts of all diagnostic devices are well developed Frequent design discussions amongst LUSI and LCLS scientists EOS device was successfully deployed at SPPS 1 st articles will help LCLS commissioning/operation and early sciences on LUSI instruments LUSI EOS will aid LCLS e-beam diagnostics LUSI BPM could aid LCLS e-beam fast feedback system Ready to proceed with baseline cost and schedule development