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Ptrel fits and SF c. Daniel Bloch , B. Cl ément, D. Gel é, S. Greder, I. Ripp-Baudot (IReS Strasbourg). Refreshing of the Ptrel fits with JLIP How to estimate SF c or SF . Ptrel fits.
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Ptrel fits and SFc Daniel Bloch, B. Clément, D. Gelé, S. Greder, I. Ripp-Baudot (IReS Strasbourg) • Refreshing of the Ptrel fits with JLIP • How to estimate SFc or SF D. Bloch (IReS Strasbourg)
Ptrel fits Reminder: for each light/c/b, have templates in bins of pt(mu) : 4-6, 6-10 (or 8-10), >10 Et(jet) : 15-35, 35-55, >55 see clued0:~bloch/ptrel/ ptrel_p1403_trigjet_corr.root ptrel_p1403_z+ttbar_corr.root and fit muon-in-jet data (with pt(mu)>8) with these templates In the “Old“ (p14 certification) analysis : used the 6-10 and >10 pt(mu) bins Now: use the 8-10 and >10 pt(mu) bins D. Bloch (IReS Strasbourg)
Ptrel fits (cont) • Discard from the ptrel fits those results which have less than 20% b-fraction: they are not stable… • Example: muon-in-jet with Et(jet)>55 GeV no-tag JLIP loose 84±6% b b-tag efficiency = 82±14% ? 16±3% b 8<pt(mu)<10 pt(mu)>10 66±4% b b-tag efficiency = 95±15% ?? 11±2% b D. Bloch (IReS Strasbourg)
Ptrel fits : loose cut Better agreement between ptrel fits and SystemD ! (but anyway just qualitative : it is SystemD which is used for b-tag efficiency computations) Old New D. Bloch (IReS Strasbourg)
Ptrel fits : medium cut Old New D. Bloch (IReS Strasbourg)
Ptrel fits : tight cut Old New D. Bloch (IReS Strasbourg)
Estimate of SFc • Idea: SFb is computed as the ratio of the b-tag efficiencies in muon-in-jet data and in the b(c) MC • An SFlight can be evaluated as the ratio of mistags in emqcd data (modulo a QCD MC correction ~0.9-1) and the tagger efficiency for light jets in QCD MC • Then SFc can be estimated by extrapolating between SFb and SFl : SFc / SFb = SFl / SFb + (1 – SFl / SFb) (εc-εl) / (εb-εl) where the εi are the MC tagging efficiencies for light, c and b. • Could do the same for SF D. Bloch (IReS Strasbourg)
SFc estimate : example D. Bloch (IReS Strasbourg)
SFc estimate : all results SFc/SFb is flat in Et : tight = 0.85±0.02 medium = 0.86±0.02 loose = 0.90±0.01 but increases with η take into account the η dependance and use as uncertainty the half-difference with 1: tight 7.5/85 = ±9%medium 7/86 = ±8%loose 5/90 = ±6% D. Bloch (IReS Strasbourg)
Summary • Better agreement on b-tag efficiency between Ptrel fits and SystemD results (just qualitative in fact) • SFc/SFb can be (indirectly) estimated on data : ~0.85-0.90 with an η dependance, and with an uncertainty of tight = ±9%, medium = ±8%, loose = ±6% • can do the same for SF (very close from SFlight) D. Bloch (IReS Strasbourg)
SFc estimate : example (cont) D. Bloch (IReS Strasbourg)