General Meeting Summary 3/28/13

BACKGROUND STUDIES/DETECTOR

• Exclusive experiments require the small beam pipe assembly allowing HMS to reach angles >=10.5 degrees. Though there may be solutions for kinematics with >=13 degrees these could only be achieved at the cost of changing kinematics and reducing the range of lever arm in Q^2. Thus dropping these smaller angles would lead to an important loss of physics.

• From WACS point of view a bigger beam pipe could be preferable depending on the relative contribution of backgrounds from target and beam pipe components.

• Scattering Chamber information:

• outer diameter = 45 inches
• inner diameter = 43.125 inches
• distance beam line to SHMS window = 1.25 inches

• So for a point target, the minimum angle is 58 mr or 3.4 degrees. For an extended target you will need to adjust, it becomes about 4 degree for a 15 cm target. So assume 3.5 degrees as rough number.

• Discussion on degradation of crystals (see Hamlet's presentation from January)

DVCS/MESON KINEMATICS

• Review and finalize kinematics table. Special meeting set up for Tuesday 2 April.

PROPOSAL PREPARATION

• Proposal submission due date is Monday, 6 May, at 8 AM.

• WACS is planning to circulate draft proposal for collaboration sign up around 20 April.

• Some discussion on the core list of collaborators for each proposal (perhaps good start is [the list of collaborators] listed on Wiki?)

• Decided on LaTeX as official :-) language for proposal writing

ITEMS FOR NEXT MEETING:

• Evaluate the fraction of background from target vs. beam line components.

• DVCS/meson final kinematics

• Based on previous proposal(s) prepare list of requests for information on technical aspects of the detector, e.g., paragraphs, figures etc. needed for the proposal instrumentation section

NEXT MEETING: THUR, 4 APRIL at 9AM (EST)