Small Angle GDH Meeting
December 06, 2002





    Alexandre Deur gave an update on the status for E97-110:
        The experiment will now run in April and May of 2003.  Alexandre went
    through a list of possible reasons for the Ice cone cell production problem.
    The production techniques were copied that were used for the production of
    cells for A1n and g2n.  The result was a 46 hour lifetime cell called Phubar.
    See the slides from Alexandre's talk for more detailed information.

        There are three good unused standard cells for two experiments, and 2 good
    Ice cone cells.  C1720 cells will be reserved for SAGDH, and the best GE180
    cells will be used for Duality.  Al Tobias brought two GE180 Ice cone reference
    cells.  But two GE180 standard reference cells need to be made, as well as
    C1720 Ice cone and standard reference cells.

     Al Tobias gave an update of the UVa target system:
       Three Ice cone cells have been filled since the last meeting, but the first
    one failed when the pumping chamber cracked during the pull-off.  A new
    holder was made to improve the pull-off.  Al discussed the changes made that
    are believed to have improved the cell production status.

    Al Gavalya discussed the design status:
        Joyce Miller is making modifications to the collimators and sieve slits.
    Modifications need to be made  for the gradient coil supports to eliminate
    interferences.

    Patricia Solvignon reported on target tests:
        Patricia gave a summary of the standard and ice cone cell performance
    characteristics.  Duke will be the first cell used during the Duality running
    period.  Duke has a lifetime of 53 hours and a max. polarization close to 47%.
    A new ice cone cell made at W&M, Veronica, had a max. polarization of ~ 24%
    without optimization.

    Vincent Sulkosky discussed the target lab status:
        From the lifetime and AFP loss tests from different parts of the cell, there was no
    significant difference in the cell lifetimes or AFP losses.

        Vince presented the results from the wall thickness measurements on Exodus and
    Veronica.  Exodus was sent to UVa to be characterized.

        Results from a crude field map in the target lab were presented.  No significant gradients
    were found.

    Todd Averett gave an update of the W&M target system:
        The most recent cell made was Veronica with a lifetime of 23 hours.  The next cell will
    be a GE180 40 cm cell with a small sphere attached to the string.  For the most recent cell,
    Todd used a cooler torch to chase the Rb.

        Todd showed the images from the glass samples that were taken with the Atomic
    Force Microscope.  The images need to be gone through, and  conclusions need to be
    drawn about what is being seen on the glass surface.

    Other issues and Manpower were discussed:
        The beam quality is a major issue for the experiment.  New harps have been installed
    in the Hall A line, but they have not been connected.  It is hoped that a few days will be
    available to test Hall A and C beam together before the Christmas break.  Aluminum
    covers maybe added to the ladder to prevent it from melting if the beam position is off.

        Todd Averett will also provide Nilanga with a Helium-4 lecture bottle to test the
    reference cell system for leaks.
 
 

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