A1n Analysis Meeting

    Xiaochao Zheng reported on the status of the A1n analysis:

- The second round of analysis has been completed with beam trips
    and EPR measurements removed from the runs
- The detector calibration has been checked
- Target analysis:  the average of the EPR and NMR measurements is
    used to interpolate the polarization for each run
- Seonho has confirmed the preliminary result
- Acceptance cut and PID dependence studies underway
- Radiative corrections have been started
    Xiaochao reported the following issues:

        - There is a 2sigma effect in both the acceptance and PID cuts, which could
            be a statistical, systematic, or software problem
        - For the x = 0.61 kinematics, there is a difference in the first (pseudo-random)
            and second (toggle) periods for the electron and pion asymmetries
        - In ESPACE, bad events were reconstructed back into acceptance
        - For the synchronization of event time and the scalar clock, ~ 15 runs are off
            by 2 seconds in the last few days of the experiment.  The change in the DAQ
            system needs to be understood for the two periods.

    In the following months Xiaochao will work on:

        - ESPACE check
        - Continue cut dependence studies
        - Radiative corrections

    Xiaochao's long-range plans are

        Target Analysis, BPM and raster corrections, Analysis on nuclear effects,
        cross section study, and extact g1 and g2.

    Nilanga Liyanage reported on the A1n analysis:

        - For ESPACE, CWN ready for both experiments, problems fixed,
           and Beta and ev_time were added to the ntuples
        - Nilanga optimized:  Beta for 2 periods of A1n, the spectrometer detector offsets,
            the VDC and scintillators
        - The absolute momentum is good to < 5 x 10^-4
        - Presently optics for the cross sections is being improved (Al Nathan's student)

    Seonho checked Xiaochao's results:

        - Seonho used the same runs as Xiaochao with the following results:

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