Standardized CCD and MCT detector mounting configurations

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Standardized CCD and MCT detector mounting
configurations

• B. C. Bigelow, UM Physics
• 2/2/05

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SiC Focal Plane Concept

• Consider SiC for focal plane baseplate
• SiC superior to Moly in virtually all material
  properties
• SiC has 5 times the specific stiffness, and 1/3
  the density of Moly
• Standard detector packages with spring preload
  mountings allow use of current detector package
  materials
• No thermal compensator / flexure mounts required
• Space heritage for SiC material, and optically
  flat mirrors established
• Substantial weight savings for focal plane
  assembly, bipods, etc.

3
SiC Focal Plane Concept

• Consider SiC for focal plane baseplate

Material Properties Molybdenum SiC (CVD)
E (GPa) 330.0 466.0
Yield (MPa) 415.0 470.0
Density (kg/m3) 10220 3210
CTE (RT, PPM/K) 5.35 2.20
K (RT, W/mK) 138 300
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Focal Plane Concept

• CTE comparison (courtesy of Pat Jelinsky)

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SiC Focal Plane Concept
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SiC Focal Plane Concept
7
SiC Focal Plane Concept

• Conclusions
• SiC is a viable option for focal plane baseplate
• Standardized detector packages are compatible
  with SiC
• Substantial weight savings are possible
• Lots more to do if SNAP project is interested in
  SiC
• Add spectrograph, guider detectors, BITE optics,
  etc.
• Add cold shield, concentrator electronics,
  radiator interface, etc.
• Detailed design of baseplate
• FEA of baseplate