SBS Optics and Spin Transport

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SBS Optics and Spin Transport

• John J. LeRose

Technical Review of the Super BigBite
Spectrometer November 17, 2008
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This is what it looks like to me!
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1st Order Optics
e.g.
Etc.
Subsequently If you know how well you can
measure x, x, y, and y, you know how well you
can determine the target parameters (provided
xtar 0)
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Projected Errors
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Higher Order Effects?

• Strategy
• Use SNAKE to create a database of trajectories
  and then fit the reconstruction tensor. (higher
  order terms)
• Use the reconstruction tensor in a Monte-Carlo
  fashion to evaluate the errors.

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(No Transcript)
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Momentum Dependence of ?O
8 GeV/c
1 GeV/c
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Spin Transport
Non-dispersive precession
Dispersive precession
Target
Target
to Reaction Plane
Reaction Plane
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Spin Transport
Because of Pl - Pt mixing, the non-dispersive
bend angle contributes a factor 100 to the FF
ratio systematic error. However, it is very
small 1.1 mrad (FWHM) and can be reconstructed
with high precision (0.1mrad).
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Still to do (optics wise anyway)

• Finalize magnet and insert 3-D map into SNAKE
• Repeat analysis described here