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L2EM TRACK MATCH. Aim: decrease L2EM rate using track match Outline: Matching studies: Method Data Zee selection L1 calorimeter towers L2CTT Results, efficiency Rejection Data Measurement Conclusion. Sabine Cr é p é -Renaudin LPSC Grenoble. Method.
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L2EM TRACK MATCH • Aim: decrease L2EM rate using track match • Outline: • Matching studies: • Method • Data • Zee selection • L1 calorimeter towers • L2CTT • Results, efficiency • Rejection • Data • Measurement • Conclusion Sabine Crépé-Renaudin LPSC Grenoble Sabine Crépé-Renaudin November 4, 2003
Method • Select good electrons from Zee (TMB) • Get their characteristics from emreco • Get the L1 calo tower info for these events • Pick raw events corresponding to the Zee selected events • Get L2 CTT info from this raw file • Compare electron characteristics, L1 cal tower info and L2 CTT info • Study L1 cal tower and CTT match • Define good matching • Measure rejection on MP triggers Sabine Crépé-Renaudin November 4, 2003
Data and code versions • Data: • P14 2em NP skim (TMB from Ulla) • Reco: p14.03.01 and p14.03.02 • Run >= 179759 (to have CTT info) • Code: • D0ChunkAnalyze (p14.04.00) (thanks to Anne-Marie help): emparticle selection + L1 calo tower info • L2 CTT readout from raw (thanks to Jan) Sabine Crépé-Renaudin November 4, 2003
Zee (I) • P14 2em NP skim, TMB format • Select good emparticles: • ID 10 or 11 • Emfrac > 0.9 • Iso < 0.15 • Eta in fiducial zone • Plot invariant mass Sabine Crépé-Renaudin November 4, 2003
Zee (II) • Final selection: • 2 emparticles with track match: e1 and e2 • pT(e1) > 15 GeV, pT(e2) > 10 GeV • Hmx8(e) < 20 • No jets in 0.7 cone from e • Run >= 179759 • Select 1000 Zee in 75-110 GeV mass window • Select only good CFT runs : 980 Z, 1960 electrons Sabine Crépé-Renaudin November 4, 2003
Electron characteristics Sabine Crépé-Renaudin November 4, 2003
L1 calo tower info (I) • For each of the 980 selected Z: • All towers with Et(tower) > 2 GeV to cut noise Sabine Crépé-Renaudin November 4, 2003
L1 calo tower match with electron • For each of the 1960 selected electrons: • Match a L1 tower in eta-phi with d < 1 Sabine Crépé-Renaudin November 4, 2003
L1 calo matched tower info • For each of the 1960 selected electrons: match • 1948 matches found (99.4%) Sabine Crépé-Renaudin November 4, 2003
L2CTT output • For each of the 980 Z events look at CTT: • 25 events have no CTT tracks (2.5 %) • ~ 5 tracks in average Sabine Crépé-Renaudin November 4, 2003
L2CTT output • For each of the 980 Z events: Sabine Crépé-Renaudin November 4, 2003
Phi match (I) • Match L2 CTT with L1 calo tower in phi • L1 towers matched with electrons • All L1 towers Sabine Crépé-Renaudin November 4, 2003
Phi match (II) • Match in phi L2 CTT with L1 calo towers matched with electrons : • Match if : • Phi(tower)-phi(CTT) > - 0.10 • Phi(tower)-phi(CTT) < 0.15 Sabine Crépé-Renaudin November 4, 2003
pT match • Match L2 CTT with L1 calo tower: match in pT not feasible • L1 towers matched with electrons • All L1 towers Sabine Crépé-Renaudin November 4, 2003
Efficiencies • 980 Z selected -> 1960 electrons • in good CFT run list and run > 179759 to have CTT • 1948 (99.4 %) L1 towers matched to these electrons • Cut dr < 1 • 1380 matched L1 towers are in CFT fiducial zone • eta < 1.6 • 2.5 % of events have no CTT tracks • 69.2% CTT tracks are matched with: -0.10 < dphi < 0.15 • 91.9% CTT tracks are matched with: -0.10 < dphi < 0.15 and L1 tower in fiducial CFT zone (eta < 1.6) In CFT fiducial zone : 1380 of selected electrons have a match with a L1 calorimeter tower 1269 (91.9 %) of them have a CTT track match Sabine Crépé-Renaudin November 4, 2003
Rejection • Data: raw data from MP trigger using EM from Marco • SAM: --dim=‘appl_name elempraw and version triglistv12’ • Subset of ~4600 events • Method: • read CTT info at raw level as previously and add L1 calorimeter tower info • Select events wrt a trigger • Triggers studied (E4_ELE_MP, 5, 6, 8, 78) • Eventually select towers and tracks • ET(tower) > 2 GeV, 3 GeV, 6 GeV • PT(track) > 5, 10 GeV • Apply match in phi • -0.10 < phi(L1 tower) – phi(CTT) < 0.15 Sabine Crépé-Renaudin November 4, 2003
Rejection: results (I) • Ex: E6_ELE_MP trigger = TIS(1,10)CEM(1,6) • 300 events triggered, 299 have CTT tracks • 218 (72 %) are matched on L1 tower > 2 GeV => Rejection : 27 % • 163 (54 %) are matched on L1 tower >= 6 GeV => Rejection : 46 % • 110 (37 %) are matched on L1 tower > 2 with Pt(track) > 10 GeV => Rejection : 63 % • 87 (29 %) are matched on L1 tower >= 6 with Pt(track) > 10 GeV => Rejection : 71 % Sabine Crépé-Renaudin November 4, 2003
Rejection: results (II) • Ex: J/Psi • E78_ELE_MP trigger = TTK(2,3)CEM(2,3) + CEM(1,6) + TTK (1,5) • ~ 120 000 events from MP selection from Marco • Ask for E78_ELE_MP + AND/OR terms • => only 4 events selected, 1 match with L1 tower > 2 GeV • => not enough stat Sabine Crépé-Renaudin November 4, 2003
Rejection: results (III) Sabine Crépé-Renaudin November 4, 2003
Conclusion • Efficiency: • 980 Z selected -> 1960 electrons • In CFT fiducial zone : 1380 of selected electrons have a match with a L1 calorimeter tower • 1269 (91.9 %) of them have a CTT track match • Rejection: • Between 60 to 70 % if cut on tower and CTT similar to L1 conditions Sabine Crépé-Renaudin November 4, 2003