Endcap Geometry update (2009)

EEMC geometry v6.0

Proposed name for the geometry file: pams/geometry/ecalgeo/ecalgeo1.g

List of changes

• CAir bug fixed
• Increased size of mother volume containing SMD strips
• Added material to front and back of SMD planes (material wrapping SMD planes)
• Added SMD spacer layers
• Introduced sector overlaps closer to the "as build" geometry
• Birk's law constants for SMD strips corrected
• Some dimention paramaters tuned to that in real geometry
• Code reorganized and commented

Note:
Lead alloy mixtures are not implemented
due to the problem with mixture in GSTAR/Geant (see below)

Resulting improvements in the simulated EEMC response

• Geometry configuration is closer to the "as build" geometry
• Correct simulation of the transverse shower shape profile
• Realistic (close to 5%) sampling fraction
• More realistic simulation of the tower energy profile (with LOW_EM option)

Supporting materials

EEMC sampling fraction nonlinearities and CAir bug

• Hal's talk at Analysis Meeting
• Keith's blog page with CAir find
• The bug report

EEMC geometry reshape

• Jason's plenary talk at LBNL collaboration meeting
• Jason's SPIN-PWG talk at LBNL Collaboration meeting (EEMC geometry revision)

Issue with mixture in GSTAR/Geant

• Lead issue (Ilya's post)
• Lead issue (Alice's post)
• Lead issue report to STARsoft-hn list

Jason's tests and studies

1. Validation of EEMC MC Geometry
2. SMD Problems at the sector boundary
3. EEmc MC Geometry version 5.21
4. Rough cut of EEMC SMD spacer geometry
5. Check of material in corrected EEMC geometry
6. Linearity Check in fixed ecalgeo.g, take II
7. Linearity Check in fixed ecalgeo.g
8. List of small, almost trivial, problems with the Monte Carlo
9. EEMC simulation study: mockup of CDF testbeam experiment
10. Verify that the fast simulator sees all of the energy deposited in geant
11. Energy dependence of the sampling fraction in the EEMC
12. EEMC simulation studies (spin-pwg-simulations-report-07-30-2009.pdf)

Ilya's tests and studies

1. new EEMC geometry: Pure lead and new SMD layers
2. Jason EEMC geometry: Effect of ELED block change
3. Jason EEMC geometry: results with and without LOW_EM options
4. Jason EEMC geometry: Jason with ELED block from CVS file
5. Jason EEMC geometry: comparison without LOW_EM option
6. Jason EEMC geometry: effect of removing new SMD layers
7. Jason vs. CVS EEMC: removed SMD layers
8. Sampling fraction problem: full STAR vs. EEMC stand alone geometry
9. Jason geometry file: Full STAR simulations (sampling fraction, shower shapes)
10. Jason geometry tests: SMD energy, number of strip vs. thrown photon position
11. Effect of added layers in Jason geometry file
12. Volume id fix in Jason geometry file
13. Jason vs. CVS EEMC geometry: sampling fraction and shower shapes
14. Test of corrected EEMC geometry: LOW_EM cuts
15. EEMC geometry tests: on-off SVT detector and EEMC slow-simulator
16. Single particle MC with corrected geometry vs. eta-meson from data
17. Corrected EEMC geometry: shower shapes
18. Corrected EEMC geometry (bug 1618)

Alice's tests and studies

1. Summary of Lead Problems
2. Further tests with lead
3. Testing changes to cvs geometry file
4. Some geometry tests