Goals

1. Goals • - Short term: • Finish merging the L1 trigger configuration files with the HLT. • When this is done, hopefully I will see that the signal increase for a given fake rate. In this way, we can see that the pixel upgrade is a worthwhile project. - Longer term: • Integrate the Long Barrel Geometry and Phase II definitions. We will have tracking for level 1 taus for the first time. • Look at the HLT in the same manner as above.

2. Tau Finding Algorithm Seed with a single tower: E.g. ET(1)>5 GeV Energy measurement in a 2x2 region (pick the one with highest sum ET):  e.g. ET(2x2)>10 GeV Shape requirement in eta-direction:  Has to be very local (or will blow up with PU): e.g. Max(ET(3x2)-ET(2x2))< 5

3. Pixel Upgrade Opportunities for Upgrade • Remove radiation damage • Lower/move mass • Bpix • Add 4th layer • Move layer 1 closer to IP • Alter pitch • Fpix • Add 3rd disk • Alter disk configuration • Streamline sensor design Improved “3 out of 4” pixel seeding has implications for the HLT that are not well understood.

4. HLT Predictions • Due to the new pixel tracks, we expect • Higher efficiency • We will find more tracks pointing to the calorimeter • Lower fake rate • With the more accurate tracks, we will be able to see if the track is really pointing to our cluster or rather in the isolation region.

5. Requirements at L1 • Level 1 • Cluster threshold 2 • Tauseedtower 10 • IsolationTauA 10000 • IsolationTauB 10000 • Isolation threshold tau 6

6. Jan 17. 2011 Requirements at L2 • SLHChltL2TauJets • Unpacks list of taujet EtMin=15 • Iterative cone algorithm with Δr=0.2 • SLHChltL2TauNarrowConeIsolationProducer • ECAL isolation, inner cone 0.15, outer cone 0.5 • ECAL clustering, cluster radius 0.08 • Tower Isolation, inner cone 0.2, outer cone 0.5 • SLHChltL2TauRelaxingIsolationSelector • MinJetEt 15, isolation Still working through this calculation

7. Requirements at L2.5 SLHChltL25TauConeIsolation - at least two pixel hits associated with the track conesize .5 - at least 5 hits in total (pixel plus strip) associated with the track - the transverse impact parameter does not exceed 300 μm - the minimum transverse momentum 1 GeV/c - the normalized chi-squared of the track fit below 100 - matching cone .2 - signal cone 0.15 - isolation cone 0.5 - minimum transverse momentum in isolation ring 1 GeV/c - maximum number of tracks in isolation ring 0 SLHChltL25TauLeadingTrackPtCutSelector - Min leading track pt > 5 SLHChltL25TauConeIsolation - at least two pixel hits associated with the track conesize .5 - at least 5 hits in total (pixel plus strip) associated with the track - the transverse impact parameter does not exceed 300 μm - the minimum transverse momentum 1 GeV/c - the normalized chi-squared of the track fit below 100 - uses a fixed cones size: signal cone 0.15, isolation cone 0.5 - min leading track pt 5.0 SLHChltL25TauConeIsolation - at least two pixel hits associated with the track conesize .5 - at least 5 hits in total (pixel plus strip) associated with the track - the transverse impact parameter does not exceed 300 μm - the minimum transverse momentum 1 GeV/c - the normalized chi-squared of the track fit below 100 - uses a fixed cones size: signal cone 0.15, isolation cone 0.5 - min leading track pt 5.0

8. Requirements at L3 • SLHChltL3TauConeIsolation • At least 2 pixel hits associated with the track • At least five hits in total (pixel plus strip) associated with the track • The transverse impact parameter does not exceed 300μm • The pt must exceed 1 GeV/c • The normalized chi-squared of the track fit below 100 • Matching cone 0.2, signal cone 0.15, isolation cone 0.5 • 0 tracks in isolation ring • Min pt in isolation ring 1 Gev/c • SLHChltL3TauIsolationSelector • Min pt leading track 5 GeV/c • SLHChltL1HLTSingleIsoTau30JetsMatch • Matches to a level 1 tau ΔR < 0.5