Optics Meeting Mar 22 2022 230PM ET
From Moller Wiki
- Brief introduction to the needs for the Sieve and Blocker collimators (David) 
- engineering considerations?
- Optics matrix elements algorithm (Hanjie, et al.)
- GEMs into remoll (Bill and Vassu, et al.)
- Dimension and configuration (Bill): 
- GEM tracker into Remoll (Vassu).
- Efficiency Table (Brynna).
David A., Bill L., Kate E., Wouter D., Ernie I., Jason B., Ciprian G., Danielle P., Chandan G., Vassu D., Hanjie L., KK, Brynna M.
- Sieve hole diameters of 1-2 mm would be hard to manufacture if we assume 9 cm length. An aspect ratio (length/diameter) of > 20 is difficult. Could possibly do using inserts. Not clear this small a diameter is needed (Hanjie has been using 10 mm diameter). HRS sieve collimator holes are 2 mm, but our requirements are different. We need to see if 5 mm diameter (or larger) can do all we need.
- "Full" blocker (annulus) is easier to build and easier to cool, so unless there are physics reasons we haven't considered, we should go for that. Less possibly of "slit scattering" problems also. Rough estimate from Jason indicates that with 300 W of deposited power for 30 min the temp rise for non-water-cooled blocker would be 150 C. Full blocker at 85 muA on lH2 target would deposit 1600 W. Likely go with a cooled "full" blocker.
- If need be for engineering/cooling, could consider Cu for blocker instead of W; would need to run simulations.
- Present G4 simulated blocked is pure W, engineering would require 90/10 W/Cu alloy; Kate should repeat G4 simulations with 90/10. Likely means that 90 mm becomes 100 mm thick.
- Engineering might prefer blocker/sieve closer to collimator 1 in Z.
- Hanjie's machine learning optics fitting code produces good results for target theta using r,r' at the GEMs as input. This is promising.
Meeting ID 970 3027 1000