Xiaochao Zheng discussed her progress on A1n Analysis:

•  Xiaochao gave an overview of A1n theories
•  The collaboration suggested that Xiaochao ask the
          theorists what region they feel that their theory comfortably
          predicts A1n behavior and for error bars on the theory
•   Xiaochao gave an update on Nuclear Corrections which include
          EMC W. Melnitchouk and effective nucleon polarization P_p, P_n
•  For A1n errors, statistical error for A1n at x = 0.61 is 5%.  The
         biggest systematic error is from the nucleon polarization
•  Made improvements on g1/F1 Fit

•  Preparation for final analysis:  Database optimization, check beam energy,
         bpm correction etc. (1 week)
•  New (final) round of asymmetry analysis (3~4 weeks)
•  Elastic analysis, N₂ dilution - (start end of July)
•  Cross section analysis, g₁, g₂ (2 months?)

    Xiaochao gave an update of the EPR analysis:

•  Analysis issues:
•  Holding field (H0) from field calibration, or from Rb
         resonance frequency
•  Note: field magnitude from EPR between 23.7 - 24.9 Gauss
•  Extract target polarization from polarization gradient
•  P_t from EPR
•  Equilibrium solution:  P_t and P_p are in equilibrium at time of
         EPR measurement
•  Dynamic solution:  For E99-117 usually 2 of 3 lasers were off.
         P_t and P_p are not necessarily in equilibrium (Gore)
•  Comparison of the two solutions show that they are close
•  The small difference between the two are probably from a
         drop in P_p due to 2 lasers being off
•  Extract P_Rb to check T_p:
•  Gordon Cates stated the the Rb polarization should be ~ 90%
•  For Gore, Tp is very precise
•  For Tilghman, Tp is different by +/- 5 degrees C
•  Xiaochao will look into her calculation, since the spin-exchange rate
         appears to be incorrect
 
• List to do:
•  Study AFP loss
•  Understand Tilghman P_Rb - T_p ?
•  Understand H0
•  Compare with NMR

•  For the old database, the central foils were ok, but the side foils
         were off by a few mrad
•  This can change the cross sections by a few percent
•  Database optimization code is almost complete (~ 1 week)
•  After optimization, foils should look normal

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