Coherent Xray Imaging Instrument

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Coherent X-ray Imaging Instrument

• Sébastien Boutet
• CXI Instrument Scientist
• June 9, 2009

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Outline

• Update since the last FAC
• KB mirrors
• New CXI layout
• Sample Chamber/KB mirror integration for the 0.1
  micron focus

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Coherent Diffractive Imaging of Biomolecules
One pulse, one measurement
Particle injection
LCLS pulse
Wavefront sensor or second detector
Noisy diffraction pattern
Combine many measurements into 3D dataset
Combined Data Set
Reconstruction
Data Frames
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CXI Instrument Location
Near Experimental Hall
AMO
X-ray Transport Tunnel
SXR
XPP
CXI Endstation
XCS
Source to Sample distance 440 m
Far Experimental Hall
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Far Experimental Hall
CXI Control Room
Lab Area
XCS Control Room
Hutch 6
X-ray Correlation Spectroscopy Instrument
Coherent X-ray Imaging Instrument
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CXI Instrument Overview
Detector Stage (upstream position)
Particle injector
LCLS Beam
Sample Chamber
Precision Instrument Stand
Detector Stage (back position)
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CXI KB Mirrors

• CXI has two sets of KB mirrors to produce a 1
  micron beam and a 0.1 micron beam
• Discussed at last FAC
• Coating
• 45 degree geometry
• Update
• Apply single coating strip (SiC)
• But leave space for at least another strip for
  later
• The 45 degree geometry was abandoned
• Benefits were not worth the risks

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New CXI Layout

• Discussed at last FAC
• Put both sample chambers in series and have each
  KB system focus at different planes
• Put KB1 system first and focus past the KB0.1
  system
• Place Be lenses between the 2 sample chambers to
  refocus the 100 nm beam into the second sample
  chamber
• Keep ability to use the unfocused beam
• Update
• The new layout was implemented
• The unfocused beam can be used in the 1 micron
  Sample Chamber

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CXI with 1 micron and Unfocused Beam
Diagnostics/ Common Optics
Diagnostics Wavefront Monitor
1 micron Sample Environment
1 micron KB
Reference Laser
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CXI with 0.1 micron Beam
Diagnostics/ Common Optics
Wavefront Monitor
0.1 micron KB Sample Environment
1 micron KB
Reference Laser
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New Layout Advantages

• Allows serial experiment configuration
• Allows separation of mirror vacuum
• Allows the use of a thin window to separate KB0.1
  mirror vacuum from 0.1 micron sample chamber
• Allows the second chamber to be removed without
  disturbing the mirrors
• Allows a user chamber to be attached if needed

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CXI 0.1 µm KB Mirrors/Sample Environment

• Purpose
• Produce a 100 nm focus
• Focal lengths
• 0.9 m for M1
• 0.5 m for M2
• Requirements
• Identical to 1 micron KB System in every way
  except for the mirror curvature
• Integrated system with 0.1 micron Sample Chamber
  due to close proximity
• Extend vacuum enclosure by 600 mm for sample
  area
• Separate both parts of the vacuum enclosure with
  valve and window

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0.1 micron KB/Sample Chamber
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0.1 micron KB/Sample Chamber
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0.1 micron KB/Sample Chamber
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Custom Valves

• 2 custom valves will be used
• First one will hold vacuum in order to vent the
  Sample Chamber
• Second valve will have a very thin x-ray
  transmissive window to separate UHV in KB tank
  from poor vacuum (10-7 Torr) in Sample Chamber

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Summary

• The CXI KB mirrors will use a SiC coating strip
• Space will be left available for another coating
  strip once some LCLS experiments have occurred
• Use 2 sample chambers
• One for each KB mirror pair
• CXI abandoned the 45 degree KB mirror
  configuration
• Maintain the ability to use the direct unfocused
  beam into the 1 micron Sample Chamber
• The 0.1 micron KB/Sample Chamber System will
  utilize custom valves to allow venting of the
  Sample Chamber and a thin window to separate the
  vacuum of the mirrors from the sample