General Meeting Summary 4/18/13

BACKGROUND STUDIES/DETECTOR

• Draft of proposal appendix in progress. The draft (in LaTeX format) and figures will be posted on the Wiki.

• Some discussion of choice of minimum angle magnet bore vs. acceptance for DVCS, advantage of horizontal fields for RCS, and radiation damage for PbF2. These points will be re-visited for the equipment proposal.

PROPOSAL PREPARATION

• SIDIS:

• discussion of initial proposal draft. It is still work in progress, needs work, e.g., text, figures, etc.

• WACS:

• Simulations were done for all kinematic settings assuming 10-cm long target, 6% radiator, beam energies 8.8 and 111 GeV, and beam current of 60 uA. Simulations show reasonable multiplicities and radiation damage. No curing will be needed during the experiment.
• Proposal draft will be available within a week

• DVCS:

• discussion of initial proposal draft
• Theory section was updated with new theoretical developments over the last five years.
• Since last week a more realistic model was implemented and updated simulations were done for all energies. The new model is from D. Mueller. The previous model used did not describe the DVCS experimental cross section data including those measured in Hall A. The updated projections are shown in the proposal draft for representative points from the kinematic settings for Rosenbluth separation, low-x, and high-Q2. The blue band denotes systematic uncertainty.
• For the high-Q2 setting a bug was fixed in the error calculation and points were re-binned in fewer bins.
• Discussion on additional model calculations, e.g., with VGG model
• DES pi0 production will be integrated in the proposal. Some discussion about text and projections. e.g., text should include role of regular and transversity GPDs.

ITEMS FOR NEXT MEETING:

• Updates from experimental proposal preparations

• DVCS/meson kinematics table with final currents/luminosities

• Post instrumentation appendix on Wiki

NEXT MEETING: THUR, 25 APRIL at 9AM (EDT)