tttt fake rate Nick Amin June 14, 2018 Overview Reminder Last - - PowerPoint PPT Presentation

tttt fake rate

Nick Amin June 14, 2018

• Reminder
• Last set of slides here
• Re-tuned multi-isolation WPs for 2017 to lower fake rate
• Fixed bug in process — muon and electron (ptratio,ptrel) cuts were

swapped in measurement region

• Muon FR was probably higher than it should have been
• Electron FR lower than should have been
• Want to now revisit closure with updated WPs and bugfix
• Reference links:
• old FR 1D/2D maps
• old FR closure
• new FR 1D/2D maps, new EWK fits
• new FR closure

Overview

2

• From "old" to "new",

QCD FR drops by ~40% as we expected

• Data still in

disagreement with QCD at 15<pT<40

FR vs pT

3 OLD NEW

• Previously, total closure was within a percent (luck?), but pred/obs high for muons and low for electrons
• Now, closure for electrons spot on (<0.1% — luck), but muons are a factor of 2 low

Closure (HT)

4 OLD NEW e+𝜈 𝜈 e

• Also compare match type (unmatched/light vs b vs c)
• Similar trends in both — under/over predict b fakes for 𝜈/e

Closure (type)

5 OLD NEW e+𝜈 𝜈 e

• Strange that muons are off by so much, but now I think we’ve

reduced two problems (muons, electrons) to one (muons)

• Doing some synch exercises between LeptonBabyMaker and FT/

SS babymaker to make sure IDs/ptrel/ptratio are consistent

• Found some inconsistencies at per mille level for

computations involving 4-momenta

• Found per mille issue with trigger emulation for electrons
• Fixing the above didn’t change anything

Next steps

6