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Tau HLTrigger Optimization

Mike B 13 th Nov. Tau HLTrigger Optimization. Samples. SIGNAL: Z tau tau hadronic sample 50 K events in CMSSW 1_6_0 QCD : 7 bins sample 50K events/bin and Cross Sections (pb) ‏ 0-15 GeV (5.52E10) 15-20 GeV (1.46E9) ‏ 20-30 GeV (6.32E8) ‏ 30-50 GeV (1.63E8) ‏ 50-80 GeV (2.16E7) ‏

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Tau HLTrigger Optimization

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  1. Mike B 13th Nov Tau HLTrigger Optimization

  2. M. Bachtis - UW Samples SIGNAL: Z tau tau hadronic sample 50 K events in CMSSW 1_6_0 QCD : 7 bins sample 50K events/bin and Cross Sections (pb)‏ 0-15 GeV (5.52E10) 15-20 GeV (1.46E9)‏ 20-30 GeV (6.32E8)‏ 30-50 GeV (1.63E8)‏ 50-80 GeV (2.16E7)‏ 80-120 GeV (3.08E6) 120-170 GeV(4.94E5)‏ These two are totally cut in L1 This has 20 events with same energies , eta and phi for jets ... MC fluctuation

  3. M. Bachtis - UW What do we have from last week Weights applied to the QCD samples according to bin cross sections The good tau is defined as an HLT tau that: is in acceptance and is matched to the MC is matched to a matched L1 tau that passed the L1 Trigger Matched to a corresponding off-line tau (this does not cut anything significant for now) All matching delta R cuts are on 0.5

  4. M. Bachtis - UW Clarifying the good tau for the L1 For the matching to the L1 trigger we match the L2 Tau to a L1 Tau that is matched to a MC truth tau that comes from Z... One more requirement is that this L1 tau must pass the L1 Trigger and especially one of the L2 Tau Paths (minimum threshold = 20 GeV)‏ So the event must pass the L1 trigger AND The L1 Tau must pass the L1 Trigger Recall that due to the corrections the L1 Tau will have 10GeV to pass the trigger.. I have access to the corrected Energy L1 Taus So I want this L1 Tau to have a corrected energy of 20 GeV to suppose that the L1 Tau passed the trigger...

  5. M. Bachtis - UW ECAL Fraction of energy cones Signal QCD

  6. M. Bachtis - UW ECAL Isolation Cut Investigation( Big cone 0.5)‏ Signal---------- ~63% < 1 GeV ~80% <2 GeV ~88% <3 GeV Signal QCD

  7. M. Bachtis - UW Stability of the ECAL Absolute Cut QCD Signal

  8. M. Bachtis - UW ECAL Standalone Cut Efficiency with ref to L1 Efficiency is defined with refference to the L1 (before and after the cut)‏ Sorry for the errorbars! (will be there next time)‏ Note that efficiency is not energy dependend-threshold like I would like it to be because we want the trigger to have quality purposes not only background reducing.. The global-cut that I add later does it ... QCD Rates 13%,33%,43% Let's hold from here that a cut on 3 GeV reduces QCD by a factor of 2 and leaves 90% of the signal(This is good) 3GeV 2GeV 1GeV

  9. M. Bachtis - UW HCAL Energy Fractions in cones Signal QCD

  10. M. Bachtis - UW General Jet Plots QCD Signal

  11. M. Bachtis - UW Jet Energy weighted variances Signal QCD

  12. M. Bachtis - UW JetI Info based Cut Info (Standalone)‏ Let's take as cut the fraction of the Jet Et divided by the Number of Towers with 90% of energy.. Seems to be good... Energy dependance so high energy taus pass. We like Higgs to tau tau so this is good On the other hand on QCD High energy means more towers usually... No more words the stability will be discussed on next slide Only that a good cut is for CUT >=4 we have 30% of QCD passing . The idea is to combine it with the loose ECAL Cut Signal QCD This is some Med-High Pt QCD mostly 50-80

  13. M. Bachtis - UW Energy Dependance for signal and background I believe that each nice line in this nice correlation plot (for signal) shows the distribution of energy on calotowers.. Two different lines show that one or more more towers were added to the jet so the slope becomes smaller and the towers concentrate energy. There is not for QCD so it is a good pattern ... We could try a diagonal cut .. Signal QCD

  14. M. Bachtis - UW Standalone Effciency of this cut This is a high pass filter and this is something that I think is good The average rates are 87%,74%,61% The QCD rates are 27% 17% 10% We can combine this trigger and the ECAL trigger to optimize a bit better ... One example follows Note that QCD rate increases with energy for Et <80 and then falls 4 5 6

  15. M. Bachtis - UW Combined Cut Let's take the loosest configurations of the ECAL and HCAL cuts ECAL cut<3 HCAL cut>4 Signal rate = 80% QCD weighted rate 19.3% In this cut QCD rate is monotonically decreasing as a function of Jet Et

  16. M. Bachtis - UW Conclusion/Next steps Conclusion Using combined cuts we can reduce QCD by a factor of 5 without significant losses A factor of 10 is possible with some signal losses The good point is that the cut lets good high energetic narrow jets to pass the trigger(it is quality dependent)‏ We can search it further for possibly smarter cuts One other issue is the finalization of the L1 Trigger which will define the input to this trigger Next Define the efficiency as a function of reco data PF gives higher reco efficiency than CaloTau This is not expected- I have to ask! That's why I said that matching to a matched PF tau does not cut a lot in the beginning

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