Questions to Physics GroupsInformation 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 1-3x1034

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 ET or pT sums....

• Advantages and disadvantages of single-object triggers with raised thresholds c.f. multi-object

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• What follows is a short summary provided by Physics group Trigger reps. • Full answers are attached to Twiki: TriggerWorkshop2012

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 pT~10-20GeV

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Monika Wielers for SM Group

• Direct photons:– Same as 2012: cover spectrum in 20GeV steps using prescaled triggers– For di-photon σ the pT 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 pT 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)

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+g and m+g trigger– Most difficult Z(->νν)g : 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)

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• W– Use single lepton trigger pT 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

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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 ET 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 fromttbar decay

Attila Krasznahorkay for Top group

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Stefano Rosati for Higgs group

Already using di-lepton & combined triggers:

Isolated single lepton triggers:

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7Meff=MET + for MET & pT above cut.

Anna Sfyrla for SUSY groupAlready relies on multi-object triggers:

∑ jet p T

HT=scalar sum of jet pT

MHT = neg. vector sum of Jet pT

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Contransverse Mass: Di-jet MCT trigger:

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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 pT non-isolated lepton triggers to regain efficiency losses. Will rely on fat-jet triggers

Emanuel Strauss for Exotics Group

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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 pT 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.

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B-Physics Trigger - 12012 : 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 problemCurrent 1.e34 menu has no L1_2MU6, lowest unprescaled di-muon trigger is L1_2MU11Significant 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

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• 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 - 2Different B sub-groups have different requirements for trigger:

• B->JpsiX • Yield important but also precision for

CPV meas. (better at higher pT, 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 analysis Yield

2mu6 100%

mu6mu10 56%

2mu6_BarrelOnly 50%

• 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 pT muon trigger probably better than mid-pT di-muon trigger

• Requiring 3 muons with one in barrel may also be possible, e.g. 3MU4T_MU4B.