Tuesday, Jul 9, 2013 11:00am EDT
From Hall A Wiki
Logistic information
Phone number: 1-866-740-1260 Access code: 1978431#
Agenda
http://ace.phys.virginia.edu/MollerSpectrometer/259
Minutes
Attendance: Wouter, Seamus, Nilanga, David A., Rupesh, Mark P.
- Dave A.
- 4 GEMs, provide wiggle room for inefficiencies and failures
- Nilanga:
- ~95% efficiency - what we have measured so far
- GEMs need to be out of vacuum
- Need not worry about vacuum
- With GEMs we can have resolution of about 100 um or so.
- Can we improve th-th_rec by using 100 um instead of 500um
- David A./Seamus:
- We need to be using r/dr as cuts, not th
- David A.
- Mark P.
- The detector scans needed for Moller events, not ep
- David A.
- Interested in Moller asymmetries
- Collimator motions are important
- Maybe eps will be sensitive to small angles
- Mark P.
- Tolerances of positioning collimator hole
- Does this change the distribution of millers, eps at the detector?
- Things to do:
- Inner/out collimator motion
- p6. plots with GEM resolution much worse
- If 100um GEM res reduces the diff widths, then good,
else these widths are not determined by the tracking system.
- Seamus
- 5m between the first and last GEMs -> Move the first/second GEMs closer to downstream GEMs
- David A.
- Main purpose of good resolution is to verify that we have valid tracks
- The distributions that we have are not going to change very much with resolution, I suspect