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MIE Physics Requirements. Jerry Hastings. Outline. Experiment definition: the process and outcome User interactions: Oct 2004 Workshop Detector development Summary. Letters of Intent. User Program Schedule. Letters of Intent. Types Category A: Complete Endstation
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MIE Physics Requirements Jerry Hastings
Outline • Experiment definition: the process and outcome • User interactions: Oct 2004 Workshop • Detector development • Summary
Letters of Intent User Program Schedule
Letters of Intent • Types • Category A: Complete Endstation • Category B: Specific Science Goals • Category C: Technical Innovations • Response • Total of 32 received • 256 Independent investigators • 91 Institutions
Roger Falcone - UC Berkeley, USA, Chairperson Nora Berrah - Western Michigan University, USA Phil Bucksbaum - University of Michigan, USA Robert L. Byer - Stanford University, USA Hans Frauenfelder - LANL, USA Wayne Hendrickson - Columbia University, USA Stephen R. Leone - UC Berkeley, USA Margaret Murnane - University of Colorado-Boulder, USA Jochen R. Schneider - HASYLAB, Germany Francesco Sette - ESRF, France Sunil Sinha - UCSD, USA Dietrich von der Linde - University of Essen, Germany LCLS SAC
LCLS SAC Response • Draft Final Report • Identified 5 Thrust Areas • Atomic Molecular and Optical Physics • Pump/probe high-energy-density (HED) physics • Nano-particle and single molecule (non-periodic) imaging • Pump/probe diffraction dynamics • Coherent scattering at the nanoscale
LCLS SAC Response (cont’d) • All LoI’s were reviewed and fit into thrust areas • Supported Short pulse (beyond baseline) R&D • Will enable new science • LCLS efforts in AMO and detector development (endstation systems) important for early turn on
Femtochemistry Pump/probe diffraction dynamics Nanoscale Dynamics Coherent scattering at the in Condensed matter nanoscale Atomic Physics Atomic Molecular and Optical Physics Plasma and Warm Dense Matter Pump/probe high-energy- density (HED) physics Structural Studies on Single Nano-particle and single Particles and Biomolecules molecule (non-periodic) imaging FEL Science/Technology SLAC Report 611 Program developed by international team of scientists working with accelerator and laser physics communities First Experiments-SAC Response
Thrust areas: SSRL/LCLS Contact (1) Coherent scattering at G.B. Stephenson* S. Brennan the nanoscale K. Ludwig (2) Pump/probe diffraction K. Gaffney* A. Lindenberg dynamics D. Reis J. Larsson (3) High energy density R. Lee* J. B. Hastings (HED) physics P. Heimann (4) Nano-particle/single J. Hajdu* J. Arthur molecule(non-periodic) J. Miao imaging H. Chapman (5) Atomic, molecular, L. DiMauro* J. B. Hastings and optical science N. Berrah * Team leader
Team Responsibilities • Thrust area teams responsible for the science • Thrust area teams provide the specifications for the instruments • Collaborate on the conceptual design • As appropriate given responsibility for construction of specific components
Charge: Oct 25-26 Workshop • Review/refine science case as input to the conceptual design • Create a preliminary conceptual design • Review detector specifications; provide signal calculations to support rate, pixel size, area • Define space requirements • Laser specifications (associated space) • Identify CRITICAL R&D needs for the success of the conceptual design Teams will provide this information in 2-3 weeks
AMOS Equipments needs • Sub-10 fs amplified CEP laser system, crystal based harmonic source, • 10 mJ, Ti-S, for pumping tunable laser. • Monochromator for low hv (below 800 eV) • Lower photon energies (C edge) • Laser ablation system to generate metal clusters • Energy tunability 800-1000 eV, resolution of 10-4. • Ion source (ECR/EBIT?) • 2D and 3D detectors, multi-hit with energy resolution • He cryostat for cluster source (including metal clusters). • Streak camera
AMOS R&D Needs • LCLS Pulse characterization; energy, spectral, spatial and temporal • Support to Theorists for modeling and predictions • Imaging of fast (keV) electrons • High readout detectors. • Synchronization between laser and LCLS pulse (pump-probe) • Non-collinear/collinear X-ray delay line • Efficient imaging detections of particles (ions, cluster fragments….) • KB focusing pair (micron spot size, for soft x-rays) • X- ray Interferometers development (3-10)
Line width: ~ 1 mrad Van Hamos crystal spectrometer [curved] CCD active area: 0.2 rad 0.2 rad Wavelength 10 cm 10 cm Improvements of the x-ray detector will allow scattering with <1012 photons IV. Collected fraction: 0.1 rad 1 mrad 1% / 4 ≈ 10-7 Solid angle along spectral line Solid angle of spectral line CCD efficiency Assume 1012 photons at the sample [1/300] Improve collection fractions with efficient CCD [1% 60%] Improve solid angle using Van Hamos crystal [0.1 rad 0.2 rad] Photons collected: 1012 3x10-3 10-5 ≈ 30,000 Flat crystal spectrometer Line width: ~ 1 mrad CCD active area: 0.1 rad 0.2 rad Wavelength 10 cm 10 cm
PUMP-PROBE DIFFRACTION Experimental Needs (1) Modular design: 1) necessary to facilitate off-line experimental preparation 2) allows insertion of optical set-ups constructed off-site 3) uncertain how this should be accomplished Movable sample manipulation and x-ray detection 1) sustains alignment – requires facility determined x-ray positioning control 2) allows access to x-ray hutch to prepare for experiments
PUMP-PROBE DIFFRACTION Experimental Needs (2) Assumed baseline parameters to be addressed in the LCLS design 1) x-ray beam position and intensity profile 2) x-ray spectrum – spikes? 3) relative timing diagnostics and phase locked Ti:sapphire seed pulses X-ray optics 1) a mirror and a monochromator to get rid of the background radiation 2) focusing optics for variable fluence – will not change k-resolution 3) focusing optics for small protein crystals laser performance 1) 1 mJ per pulse tuneable laser light: 1 eV to 6 eV in 30 fs FWHM pulses 2) adjustable laser band width pulse duration – stretcher design? 3) pulse shaping capability – critical to coherent phase transition experiments 4) H2O and CO2 free air should be want to generate mid-IR laser light sample manipulation 1) variable thickness liquid jet – capillary as back-up 2) protein crystallography goniometer – compatible with fast multiplexing of very small crystals
Experimental Needs (3) 3rd harmonic or multiple detectors Liquid Scattering annular detectors advantageous – Development at APS will saturation of Bragg peaks make it difficult to determine width change? Diffuse Scattering
IMAGING LOW FLUENCE INSTRUMENT SCIENCE: Imaging of nanocrystalls and non-periodic nanomaterials, using multiple exposures • Pulse length not critical for imaging, • Large diameter beam (150 micron-1 micron) with large transverse coherence length, • Semi-macroscopic samples, • Automatic sample changer, • Semi-conventional sample environment (Cryo-EM sample holder/diffractometer), • Monochromator (delta lambda/lambda = 10-4), • Medium high vacuum (~10-4 mbar) or wet He atmosphere, • Lasers for reaction initiation, • Video microscope for sample alinement, looking down the beam. • Detectors: • - 1/ Area detector (2k x 2k, ~100 mm x 100 mm), 50-100 micron pixels, (dynamic range >104), • 2/ Large area detector (commercial, ~300 mm x 300 mm), 50-100 micron pixels, (dynamic range ~105), LOCATION in the far hall: large and highly coherent beam (need large optics)
IMAGING HIGH FLUENCE INSTRUMENT Single shot experiments • Extremely short pulses (1-50 fs), • Tightly focused beam (100-5000 nm Ø), • Single shot experiments on nanocrystals, particles and biomolecules, • Small area detector near the sample (dynamic range >104), • Sample injector and cryo-EM sample holder, • High vacuum (10-6-10-8 mbar), • Extended diagnostics (mass spec, ion and electron spectrometer, fluorescence detector) • Lasers sample manipulation, reaction initiation • Detectors: • Dual Area detector (≥ 1k x 1k, ~50 mm x 50 mm), 50-100 micron pixels, (dynamic • range ≥104 per detector) LOCATION in the near hall: intense beam, small beam size, small optics (low Z)
XPCS Detector Specifications Detector #1: 6 - 12 keV (monochromatic) Angular resolution: 4 microradians Sample to detector: 5 m (depends on hutch) Pixel size/spatial resolution: 20 microns Area: ~100 modules each of ~106 pixels; small dead space between modules in one dimension DQE: >0.5 Typical signal rate: average 0.01 count per pixel per pulse Noise: Need to discriminate pixels with one photon, two photons, and more photons. Error rate in determining double hits less than a few percent. Pre-processing: Algorithm to locate photon positions Max signal rate: ~100 photons per pixel per pulse Frame rate: 120 Hz, although not highest priority
Detector Specifications Cont’d Detector #2: 12 - 24 keV (monochromatic) Angular resolution: 2.3 microradians Sample to detector: 5 m (depends on hutch) Pixel size/spatial resolution: 12 microns Area: ~100 modules of ~106 pixels; small dead space between modules in one dimension DQE: >0.5 Typical signal rate: average 0.01 count per pixel per pulse Noise: Need to discriminate pixels with one photon, two photons, and more photons. Error rate in determining double hits less than a few percent. Pre-processing: Algorithm to locate photon positions Max signal rate: ~100 photons per pixel per pulse Frame rate: 120 Hz, although not highest priority
XPCS Conceptual Design: Beamline Layout Far exp. hall Hutch Defining apertures Detectors Pulse Splitter Focusing Optics Alcove Horiz. offset monochromator 10 m 5 m Transmitted Beam Sample ~100 m
2d- X-ray Detector Pump/probe diffraction dynamics Coherent scattering at the nanoscale Atomic Molecular and Optical Science (soft x-ray) Pump/probe high-energy-density (HEDS) science Nano-particle and single molecule (non-periodic) imaging
Time schedule • By Oct. 15, 2004 Specifications to LoI groups • Dec. 15, 2004 Detailed proposals due addressing: • R&D • Construction • Integration (software and hardware) • Jan-Feb 2005 Review by external advisory committee
LCLS Detector Advisory Committee (LDAC) • Advise both LCLS and the MIE on detector development • Meets on a regular basis to evaluate progress on R&D and construction • Membership • Dr. Gareth Derbyshire, RAL Chair • Prof. Y. Amemiya, Univ. of Tokyo • Prof. Dr. A. Walenta, U. of Siegen • Prof. Dr. L. Strüder, MPG • Dr. E. Eikenberry, PSI • E. Heijne, CERN
‘General’ Specifications for imaging and pump-probe diffraction
Proposals • Denes et.al. Imaging/p-p diffraction • Westbrook et.al. Imaging/p-p diffraction • Rehak et.al. Imaging/p-p diffraction XPCS • Gruner et.al. Imaging/p-p diffraction (LCLS)
LDAC Recommendations and general observations Costings of data correction, reduction (where appropriate) and manipulation: Identify where funding / responsibility for this important aspect. For each funded project there should be: Detailed set of deliverables including timescales, spend profile and major milestones. LCLS staff assigned to ensure that the detector system interfaces with the LCLS experimental program. The software requirements need to be specified for the detector system together with an interface specification to transfer data to LCLS data acquisition. A set of calibration and test procedures needs to be identified and specified within each funded project to ensure final performance is measured against original specification.
The Committee would be happy to receive 6 monthly reports from the funded proposals and to meet once a year to review progress. All proposals that include direct detection of X-rays did not address the spreading of charge between pixels that would decrease the overall signal to noise performance. This is normally made worse with thicker silicon (diffusion time related). Assign the detector development projects to experiments. This will provide detailed experiment dependent detector specifications
The thinking of the Committee was that the BNL proposal looked like a cost effective way of producing X-ray Detector 1 and went a significant way to producing a solution for X-ray detector 2. The full specification for X-ray detector 2 appeared to be limited by the fabrication facilities currently available at BNL. If enhancement of fabrication facilities allowed the production of X-ray detector 2, and the cost was not too high, this may form the most cost effective solution for a suite of detectors for LCLS. The LCLS should encourage and support BNL to improve their facilities.
Summary • Experiments chosen through an open process • Teams and team leaders are chosen • Workshop in Oct. 2004 began the definition of specifications • LCLS Detector Advisory Committee has advised on the path forward for 2d x-ray detector development