...
Name | Purpose | Gamma Efficiency | Bkg Efficiency | Cut | ||
|---|---|---|---|---|---|---|
VetoHit1Cut | Reject events with best track pointing a struck tile/ribbon | 94.5% | 14.2% |
| ||
TotalTileEnergyCut | Reject events with excess ACD total energy | 86.5% | 2.44% |
| ||
VetoGap1Cut | Reject events in gaps of the ACD | 86.2% | 2.42% |
| ||
VetoHitCut | Reject events if other track points at hit tile | 86.1% | 2.35% |
|
Conclusions
Well, it doesn't seem like we are where we want to be (not a surprise). It looks like we would like to roughly double the background rejection (1/2 the efficiency) for the Pass 8 analysis with the AcdReconV2 variables. However, it appears that the simple cuts with AcdReconV2 are roughly comparable to those with the original AcdRecon, meaning that the degredation in background rejection is in part due to upstream reconstruction changes (which in any case are not yet complete).
Looking Forward
- Can we easily modify the AcdV2 cuts to increase background rejection with the current reconstruction?
- Right now AcdV2 is using the G4 propagated covariance matrix, which really isn't right for cosmic-rays (since it uses electron hypothesis). Would changing this make an improvement?
- How do the CalOnly events look? Can we develop some rough background rejection for them?
- Obviously this will improve as the upstream reconstruction improves. Can we provide any guidance for that?
- CTs are always the after-burner to get the boosted rejection power that we need.