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SBS Optics and Spin Transport. John J. LeRose. Technical Review of the Super BigBite Spectrometer November 17, 2008. This is what it looks like to me!. 1 st Order Optics. e.g. Etc.
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SBS Optics and Spin Transport John J. LeRose Technical Review of the Super BigBite Spectrometer November 17, 2008
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)
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.
Momentum Dependence of ΔΩ 8 GeV/c 1 GeV/c
Spin Transport Non-dispersive precession Dispersive precession Target Target to Reaction Plane Reaction Plane
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).
Still to do (optics wise anyway) • Finalize magnet and insert 3-D map into SNAKE • Repeat analysis described here • …