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JetMET Triggers for L=2e30 and L=2e31

JetMET Triggers for L=2e30 and L=2e31. JetMET/QCD Task Force Leonard Apanasevich (UIC) Jochen Cammin (Rochester) Rob Harris (Fermilab) Greg Landsberg (Brown) Nikos Varelas (UIC). Introduction. Review proposal from Trigger Studies Group for new 2e30 and 2e31 trigger menus

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JetMET Triggers for L=2e30 and L=2e31

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  1. JetMET Triggers for L=2e30 and L=2e31 JetMET/QCD Task Force Leonard Apanasevich (UIC) Jochen Cammin (Rochester) Rob Harris (Fermilab) Greg Landsberg (Brown) Nikos Varelas (UIC)

  2. Introduction • Review proposal from Trigger Studies Group for new 2e30 and 2e31 trigger menus • Recommendations from the JetMET/QCD trigger task force: • Single jets • Dijet balance • Missing ET • Photons JetMET meeting

  3. Proposed 2x1030 HLT Menu From Wesley’s talk yesterday JetMET meeting

  4. Proposed 2x1031 HLT Menu JetMET meeting

  5. Proposed Jet Thresholds Total: 49.2 Hz Total: 30.8 Hz 1e32 rates obtained by scaling 2e31 rates JetMET meeting

  6. Level-1 Turn-On Curves CMSSW 160 • L=1e32 menu had L1 threshold at 30 GeV for HLT path with 60 GeV threshold • Should be save to use pT = 50 GeV threshold at HLT with L1 threshold at 30 GeV • Also considering pT=180 GeV threshold at HLT instead of 200 GeV with L1 threshold at 150 GeV • Curves obtained using dijet MC samples with 15 < pT hat < 300 GeV • may bias lowest threshold plot somewhat • L1 energy scale a bit off due to correction being derived in CMSSW 13x JetMET meeting

  7. Recommendations for Jets Red highlights indicate new paths Green highlights indicate updated prescale values JetMET meeting

  8. Dijet Balance Triggers K. Kousouris Single Jet Trigger (110 GeV) Dijet Triggers Single jet triggers can be used, but most events get thrown away. Better to trigger on the quantity you’re binning in: pTDijet = (pTProbe + pTControl) / 2 JetMET meeting

  9. Dijet Balance Triggers (ii) K. Kousouris • Dijet balance triggers use same L1 trigger bits as single jet triggers • HLT selects on ave. pt of uncorrected jets: pTDijet = (pTProbe + pTControl) / 2 • Extra rate accounted for by lowering some prescale factors in single jet paths JetMET meeting

  10. Recommendations for Missing ET • Can run L1_ETM45 unprescaled at 1e32 (~0.5 kHz) • Need only 3 unique L1 bits to cover luminosities to 1e32 cm-2s-1 • Important since L1 bits are somewhat precious • Probably can combine HLT prescale with L1 prescale for most of these paths JetMET meeting

  11. Single Photon Thresholds • Level-1 e/γ algorithms require that h/e in the hit tower is less than 0.5% • Dangerous at startup since the noise levels will probably not be well known • Similar concern for the tightness of the fine grain requirement • See next slide JetMET meeting

  12. Level-1 EM Trigger Algorithm • E/γ (Hit Tower + Max) • 2-tower ET > threshold • Hit tower H/E < 5% • Hit tower 2x5-crystal strips >90-95% of tower ET in 5x5 (Fine Grain) • Isolated E/γ (3x3 Towers) • Quiet neighbors: all towerspass Fine Grain & H/E • At least one of the 5-tower corners has ET < threshold (~1 GeV) Sum ET of the central hit tower (pink) andthe nearest neigbor w/ the highest ET (one of the yellow towers) JetMET meeting

  13. Request one L1 “pass-through” trigger for the lowest threshold paths for Jets, MET and Photons to measure lowest threshold HLT turn-on Use min. bias to measure lowest threshold L1 turn-on Remove redundant pT=40 and pT=60 GeV jet thresholds from menus Introduce realistic thresholds for dijet balance paths Need low threshold missing ET paths even at startup to help understand the trigger Prescale away if rate is too large Concern about L1 e/γ algorithm’s e/h and fine grain requirements being too tight at startup Summary JetMET meeting

  14. Backups JetMET meeting

  15. HLT Selection of Photons and Electrons • Electrons: • Supercluster matched with L1 triggers with energy satisfying the L1 trigger threshold • HCAL Energy within ΔR<0.15 from the candidate less than a threshold • Pixel match (or inner SiStrip matching) • E/P for single electron trigger • Pt Tracks with 0.02< ΔR<0.2 divided by Pt electron less than a threshold • Photons: • Supercluster matched with L1 triggers with energy satisfying the L1 trigger threshold • ECAL Energy within ΔR<0.3 from the candidate less than a threshold (excluding the super-cluster itself) • HCAL Energy within ΔR<0.3 from the candidate less than a threshold • Number of tracks with ΔR<0.3 from the photon candidate less than a threshold JetMET meeting

  16. HLT Selection Requirements • HCAL isolation criteria changed from EHcal < 3 GeV to EHcal<3 GeV .OR. EHcal < 0.5 * EEcal • The E/p cut is to be replaced by |1/E -1/p|. Probably will not be applied at the start-up or for low luminosity (below 1032 cm2s-1) running JetMET meeting

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