Agenda

1. Update on GEM efficiency map [Nathan and Bill]

2. Low energy photon implementation [Bill]

3. Sieve hole locations [Vassu and Kate][1]

Attendance

David, Vassu, Zuhal, Bill, James, Nathan, Kate

Nathan is working in implementing a simple "efficiency map" for the GEMs into remoll, to account for the active area and the expected efficiency "holes" at the HV ribs. Horizontal ribs incorporated for now. We should plan on including the correct thickness of frame material into remoll.
Still working on debugging of the low-energy photon physics list implementation for remoll.
Vassu/Kate: verified that we can still reconstruct v_z from the two foils using GEM_r and GEM_r' rather than using sieve_r and sieve_r'. Adjusted/optimized r values for the sieve holes. Used beam generator to look at whether the Moller electrons will provide an important background to the e-12C events for optics runs - do we have enough radial separation of the holes to prevent this? We see that the radial separation between e-12C and Moller events increases with increasing beam energy. Can clearly separate them for 2-pass and 3-pass data, but not at 1-pass. Reducing sieve hole diameter does not make much improvement, perhaps because of the increased relative importance of slit scattering. Probably have to rely on sectors with single hole for 1-pass measurement.

Meeting URL

Meeting ID: 972 5975 5403

Passcode: 4937