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Muon reco . efficiency status: from J/psi to Z T&P. Giovanni Petrucciani (UCSD). Outline. Introduction Results for the “Run2010A” period (before the last technical stop; about 3/pb) Turn on curves from J/Psi Efficiency on the plateau from Z
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Muonreco. efficiency status: from J/psi to Z T&P Giovanni Petrucciani (UCSD)
Outline • Introduction • Results for the “Run2010A” period(before the last technical stop; about 3/pb) • Turn on curves from J/Psi • Efficiency on the plateau from Z • New results for the “Run2010B” period(last week of running; integrated luminosity about 2/pb for Z and 1/pb for J/Psi) G. Petrucciani (UCSD)
Introduction The Tag & Probe method allows to measure the muon reconstruction efficiencies using di-muons from resonances like J/Psi and Z(see Zoltan’s talk Monday at this workshop) In this talk, I will discuss about the offline muon reconstruction and id. efficiencies. G. Petrucciani (UCSD)
Reconstruction efficiencies The efficiency to reconstruct a muon using also the inner tracker can be parametrized as eff(mu) = eff(inner track) * eff(track -> mu) The efficiency to reconstruct the inner track is approx. 100% for all muons from J/Psi and Z, so we will measure only eff(track -> mu) The measurement of the standalone reco. efficiency is more complex, as one has to handle the matching. Studies are ongoing (D. Trocino) G. Petrucciani (UCSD)
Triggers and selections • In order to collect (muon + track) pairs in an unbiased way: • For Z, we just require that the muon fires the Mu9 trigger (still unprescaled in the 2E31 menu) • For J/Psi, the situation is more difficult: At trigger level, use Mu5_Track0_Jpsi trigger At offline level, require the track to be a calo muon in order to reduce the background from muon + hadron pairs G. Petrucciani (UCSD)
Results from Run2010A era Barrel Endcaps Global muon reconstruction efficiencies G. Petrucciani (UCSD)
Results from Run2010A era Endcaps Barrel Arbitrated tracker muon id. efficiencies G. Petrucciani (UCSD)
Results from Run2010A era Barrel Endcaps Tracker muon LastStationAngTight efficiencies G. Petrucciani (UCSD)
Results from Run2010A era Barrel Endcaps Tight (VBTF) muon id. efficiencies G. Petrucciani (UCSD)
Results from Run2010A era Average Effiency Data: 98.8 ± 1.1 % MC: 98.79 ± 0.04 % PT > 20 GeV Global muon reconstruction efficiencies G. Petrucciani (UCSD)
Results from Run2010A era Average Effiency Data: 100.0 − 0.8 % MC: 99.52 ± 0.02 % PT > 20 GeV Arbitrated tracker muon id. efficiencies G. Petrucciani (UCSD)
Results from Run2010A era Average Effiency Data: 96.3 ± 1.2 % MC: 95.99 ± 0.07 % PT > 20 GeV Tight (VBTF) muon id. efficiencies G. Petrucciani (UCSD)
New results from Run2010B era Disclaimers: • These runs have not yet been certified yet.What I’ve used is: • DCS status flags of all subdetectors • Manual certification flag for Muon only(DPG flags were sometimes inconsistent beween between online and offline flags) • I didn’t process 3.8.X MC yet, so I’ll show only plots of Run2010A data vs Run2010b data G. Petrucciani (UCSD)
Run2010B vs Run2010A Barrel Endcaps Global muon reconstruction efficiencies G. Petrucciani (UCSD)
Run2010B vs Run2010A Endcaps Barrel Arbitrated tracker muon id. efficiencies G. Petrucciani (UCSD)
Run2010B vs Run2010A Barrel Endcaps Tracker muon LastStationAngTight efficiencies G. Petrucciani (UCSD)
Run2010B vs Run2010A Barrel Endcaps Tight (VBTF) muon id. efficiencies G. Petrucciani (UCSD)
Run2010B vs Run2010A Average Effiency New: 98.7 ± 1.1 % Old: 98.8 ± 1.1 % PT > 20 GeV Global muon reconstruction efficiencies G. Petrucciani (UCSD)
Run2010B vs Run2010A Average Effiency New: 99.8 ± 0.2 % Old: 100 − 0.1 % PT > 20 GeV Arbitrated tracker muon id. efficiencies G. Petrucciani (UCSD)
Run2010B vs Run2010A Average Effiency New: 96.3 ± 1.2 % Old: 96.3 ± 1.2 % PT > 20 GeV Tight (VBTF) muon id. efficiencies G. Petrucciani (UCSD)
Run2010B vs Run2010A • In general, good agreement between Run2010A (3.6.X) and Run2010B (3.8.X).Two visible differences: • Large increase in tracker muon efficiency in the endcaps for pT = 1-2 GeV (?) • Improvement in the turn on curve for tight muon efficiency (plateau value on Z unaffected) G. Petrucciani (UCSD)
Conclusions Muon reconstruction efficiencies have been measured on data using J/Psi and Z. At the current luminosities, a few days of data-taking are enough to get good quality measurements of the turn on and plateau. In general, there is good agreement between new data (3.8.X), old data (3.6X) and MC.Some differences for soft tracker muons, but in the good direction (3.8.X > 3.6.X > MC) G. Petrucciani (UCSD)