Atautau  lh Carlos Solans TileCal Valencia meeting 20th September 2007

TileCal Valencia meeting, 20th September 2007Carlos Solans2 Overview Many progress since last review Correct particle identification Exercises tryout Tau reconstruction efficiency Delta phi of tau tau candidates Data samples Cut flow

TileCal Valencia meeting, 20th September 2007Carlos Solans3 Particle identification Taus Pt > 30 GeV && |Q|=1 && |η| < 2.5 (inside LAr) #tracks=1 | 3 ΔR > 0.2 with electron or muon Likelihood > 4 (for TauRec) Districut=1 (for Tau1p3p) Electrons (EG) Pt > 25 GeV && |Q|=1 && |η| < 2.5 (inside LAr) IS_EM & 0x30F = 0 Has associated track Isolation < 0.1 (Et (cone 2.0) /Pt) Muons (Muid) Pt > 20 GeV && |Q|=1 && |η| < 2.5 (inside LAr) Isolation < 0.1 (Et (cone 2.0) /Pt) 0 < χ2 < 20

TileCal Valencia meeting, 20th September 2007Carlos Solans4 Tau reconstruction efficiency Definition Efficiency = (identified tau) / (truth hadronic tau) Plot magnitudes N(identified tau) Pt,truth / N(truth hadronic tau) Pt,truth Results The distribution looks ok (ATL-COM-PHYS )ATL-COM-PHYS Tau 1p3p has less reco efficiency but does it have less fakes?

TileCal Valencia meeting, 20th September 2007Carlos Solans5 Delta Phi Using the same particle identification. Identify candidates Hadronic tau and leptonic tau Sample has Δφ cut (0 < Δφ < 2.9) Plot delta Phi Little statistics We see the delta Phi cut.

TileCal Valencia meeting, 20th September 2007Carlos Solans6 Data samples Signal sample 25k events full simulation. MA = 150 tanb=10 with deltaPhi cut New sample full simulation. MA = 150 tanb=45 Background Ztautau: 200k events full simulation missing EF information ttbar: 200k events full simulation Would like to run over J3, J4 samples 70GB required in valtical15

TileCal Valencia meeting, 20th September 2007Carlos Solans7 Cut Flow Visible Mass Sum of 4momentums of candidates and MET Tau Reco Non back to back (cos(Δφ) > -0.9) Collinear approximation of momentum fraction carried by hadronic tau and leptonic tau 0 < xTau < 1 0 < xLep < 0.75 Preliminary results: ε(cut) ~ 1.5% #events% EF_Trigger mu20i || e25i Lepton candidate (EG, Muid) Tau candidate (TauRec)13455 MET > Tau Reco Electrons 1% Muons 0.5%

TileCal Valencia meeting, 20th September 2007Carlos Solans8 Visible Mass ttbar backgroundsignal These plots contain all momentum fractions

TileCal Valencia meeting, 20th September 2007Carlos Solans9 Expectation for 100pb -1 Normalization N = σ(sample, generator, athena) x ε(cut) x L Background ttbar sample: σ = 461pb  N~46k Signal sample (M A =150 tanβ=10): σ = 11pb  N~1k