1. Questions to Physics Groups Information requested per analysis sub-groups For 5-10 representative analyses: – representing the core physics – providing representative examples of the full range of triggers used – including new areas or areas posing a particular challenge for triggering. Examples where the offline cuts are driven by the trigger thresholds. Questions are targeted at how to maximize physics while controlling rates (L1 and HLT) for luminosities 1-3x10 34 Questions: Physics impact of increasing thresholds? At what point does pre-scaling or end-of fill trigger become preferable? Possibilities for tightening/adding cuts: Compare online and offline selection cuts Impact of replacing single-object primary triggers by multi-object triggers e.g. will be very hard to keep single e trigger threshold in 25-30 GeV range Possibilities for Topological triggers e.g. mass cuts, angular cuts, scaler/vector E T or p T sums.... Advantages and disadvantages of single-object triggers with raised thresholds c.f. multi-object 1 What follows is a short summary provided by Physics group Trigger reps. Full answers are attached to Twiki: TriggerWorkshop2012TriggerWorkshop2012

2. Feedback from SM Soft QCD: – Topological trigger could be used for : (needs to be studied for 2015) Photon induced di-lepton proc. produced back-to-back with p T ~10-20GeV 2 Monika Wielers for SM Group Direct photons: – Same as 2012: cover spectrum in 20GeV steps using prescaled triggers – For di-photon σ the p T spectrum is similar to H->γγ, use same trigger – To be studied: photon + bjet trigger for photon + heavy flavour analysis Jets – Dijet cross section: use prescaled single jet triggers starting with 50 GeV offline jets (require trigger >99% efficient for given p T bin) – Topological trigger using Δη or Δϕ cuts might help for gap fraction and azimuthal decorrelation measurements – B-jet triggers could be used for di-bjet events (to be studied)

3. SM: Electroweak, W/Z(+jets) Diboson production – Most processes triggered by di-lepton (ee, mumu, emu) ok if dilepton trigger threshold is around 20GeV (efficient at 25GeV) – W/Z gamma will rely on e+  and  +  trigger – Most difficult Z(->νν)  : relies on single photon trigger, not clear we can do this VBF/VBS WW like sign production – Signature: WW+jj, W->e/mu+ν – Use dilepton trigger (?) – Could benefit from tagging jet trigger at L2 plus lepton (similar to VBF H->ττ) 3 W – Use single lepton trigger p T thresholds not exceeding 27-28 GeV Thresholds above this will strongly affect the W eff. – Possibility to move to tight selections – Non isolated trigger prescaled by 2-3 preferable to isolated triggers – Combination with Etmiss trigger not an option: Etmiss turn-on too slow W+jets : Investigate use of lepton + jet triggers (possibly common trigger with SUSY) Z+jets : Di-lepton trigger with threshold around 20GeV will work

4. Top Triggers at High Luminosity Single Lepton Triggers: – Most 2012 analyses use these for signal – Might still be preferable in future in some cases – Could possibly tighten e trigger selection – But can’t just rely on single lepton triggers Combined triggers: – Possible to use lepton+b-jet and/or lepton+MET triggers in the lepton+jets final states – Collecting fully hadronic ttbar events will be a big challenge, will have to use triggers with 2 b-jets, and possibly use end of fill triggers – Analyses with two leptons in final state will have a slightly easier time, just by using di-lepton triggers Boosted top signatures: can raise fat jet E T thresholds a little more, but will have to use a combination of triggers to cover a large invariant mass range. (Possibly use b-tagging on fat jets?) Muons from ttbar decay Attila Krasznahorkay for Top group 4

5. Stefano Rosati for Higgs group Already using di-lepton & combined triggers: Isolated single lepton triggers: 5

6. 6

7. Meff=MET + for MET & pT above cut. Anna Sfyrla for SUSY group Already relies on multi-object triggers: HT=scalar sum of jet p T MHT = neg. vector sum of Jet p T 7

8. Contransverse Mass: Di-jet MCT trigger: 8

9. Exotics Feedback Long-Lived Particles and Lepton-Jets – mostly concerned with L1 thresholds: Something like L1_3MU6 is needed for prompt and displaced muon-jets L1_TAU40 ->L1_TAU60 as seed to CalRatio trigger would kill the signal. Investigating alternatives. L1_EM18VH-> L1_EM28H as seed to monopole trigger (g_nocut_hiptrtL2)=>efficiency losses. Hope to be able to use a TRT FastOR trigger instead.  At HLT Higher single non-isolated thresholds =>significant efficiency loss for e-jets analysis. Medium trigger electron efficiency is poor could possibly live with di-electron triggers using looser HLT cuts. Top and 4th Generation  Usually follow the lead of the top group  Need higher p T non-isolated lepton triggers to regain efficiency losses.  Will rely on fat-jet triggers Emanuel Strauss for Exotics Group 9

10. Exotics Feedback Dibosons and Multi-leptons  Primarily used single electron and single muon triggers in 2011 and 2012 Inclusive searches: concerned about high thresholds for non-isolated lepton triggers. Further studies still needed determine sensitivity with di-lepton triggers. Resonance searches: OK as long as isolated lepton trigger p T cut is 25-30 GeV. 15-20 GeV di-lepton trigger should be OK, investigating impact on sensitivity.  Searches with jet final states:  generally OK with L1 menu, but HLT cuts determine sensitivity of highest di-jet mass range Dijet cuts or jet substructure could be used for lower mass ranges.  Searches with mET final states: ok as long as offline thresholds < 200 GeV. Lepton + X  Generally OK with L1 menu, but concerned about EF selection  Typically use looser object definitions than other groups  Z' → tau tau probably ok for had/mu and had/e channels. had/had channel where thresholds are higher than the current analysis offline cuts. 10

11. B-Physics Trigger - 1 2012 : Primary triggers are 2mu6_xxxxx (xxx=Jpsimumu, Upsimumu, Bmumu, Bmumux) Also have: 2mu4T_xxxx_Barrel, 2mu4T_xxxx_BarrelOnly, mu4Tmu6_xxxx_Barrel, mu4Tmu6_xxxxxx. In Delayed Bphysics Stream - except Bmumu and 10% of Jpsimumu (for reference). Progressively prescaled as lumi increased through the year. Future: L1 rate is main problem Current 1.e34 menu has no L1_2MU6, lowest unprescaled di-muon trigger is L1_2MU11 Significant impact on Bphysics! Hard to predict low pT di-muon rates (shat scaling probably doesn’t apply to these low energy collisions, poor MC statistics for predictions, effect of 25ns unclear) Best guess ~8kHz for L1_2MU6 Would L1_2MU6_BARRELONLY or L1_2MU6_MU10 have an acceptable rate? Investigate use of Topological L1 trigger DeltaPhi for Bsmumu signal Can do more at HLT Tighter mass cuts (e.g. Psi(2S) trigger for Onia) Lxy cuts for Bmumu or require prompt events for Onia For B->JpsiX look for exclusive decays BUT main problem is L1 rate Julie Kirk for B-Physics & B-signature groups 11

12. Bmumu Rare process, want as many events as possible Implies lowest thresholds Need reference channel (B+->JpsiK+) using similar trigger to signal B-Physics Trigger - 2 Different B sub-groups have different requirements for trigger: B->JpsiX Yield important but also precision for CPV meas. (better at higher p T, in barrel) Need to find best balance of yield/precision Will also look at effect of requiring extra lepton to improve B-flavour tagging. BsJpsiPhi analysisYield 2mu6100% mu6mu1056% 2mu6_BarrelOnly50% Onia Already lots of Jpsi/Upsilon data. In future will be looking at more unusual processes, e.g. very asymmetric events, Onia+Z Single high p T muon trigger probably better than mid-p T di-muon trigger Requiring 3 muons with one in barrel may also be possible, e.g. 3MU4T_MU4B. 12