Hlt2 Inclusive muon and muon+track triggers

1. Hlt2 Inclusive muon and muon+track triggers Antonio Pérez-Calero HLT2 + Physics Meeting May-19th-09

2. Overview • Robust triggers • Single muon and muon+track in details • Performance for tested scenarios • Global HLT2 Inc. Muon rates • TIS on B→hh • Summary & To Do’s Inclusive Hlt2 mu(+track) triggers - Antonio Pérez-Calero

3. Introduction • Channels to trigger on: • Bs→mm • Bd→K*mm • Bs→J/y(mm)f (with lifetime biased or unbiased selection) • Plus semileptonics, control channels, TIS, etc. • Single muon is a robust trigger that can be used for the channels above: • Simple to test and commission • Provide robustness against intrinsic muon chambers inefficiencies • The addition of the extra track provides more info to retain efficiency while reducing output rate: • Can use low momentum muons (track can be a muon) • Also use extra particles present in the decay (track can be a pion or kaon) Inclusive Hlt2 mu(+track) triggers - Antonio Pérez-Calero

4. In details: • Single Muon: Filter Hlt2 Muons cutting in the properties of muon track • Muon+track: • Combine Hlt2 Muons with Hlt2 NoCutsPions (essentially a track, no RICH or any PID applied ) • Use both same and opposite charge combinations • We should first use robust variables, avoiding cuts on significances: • Tracks (particles): pT, IP and c2 cuts (from Hlt2 initial global reconstruction, no refit applied) • Vertices (combination): Doca, Dz, Di-Muon Inv. Mass and Pointing. • Final particle: p, pT. Inclusive Hlt2 mu(+track) triggers - Antonio Pérez-Calero

5. First scenarios We must consider several scenarios for different possible available output rates. Working points chosen to illustrate performances: • Single muon: • pT>3 GeV, |IP|> 200mm, c2/Ndof<10 • pT>3.5 GeV, |IP|> 200mm, c2/Ndof<10 • Muon + track: • Muon pT>1.5 GeV, |IP|> 200mm and c2/Ndof<30 Track pT>0.6 GeV, |IP|> 100mm and c2/Ndof<30 Combination DZ>2mm, DOCA<100mm, Inv. Mass [0.5, 6] GeV and Pointing<0.4 • Muon pT>2 GeV, |IP|> 200mm and c2/Ndof<30 Track pT>0.6 GeV, |IP|> 150mm and c2/Ndof<30 Combination DZ>2mm, DOCA<100mm, Inv. Mass [0.5, 6] GeV and Pointing<0.35 Inclusive Hlt2 mu(+track) triggers - Antonio Pérez-Calero

6. Performance study conditions • DaVinci 23r0p1 • 15k Min. Bias L0xHLT1 stripped events • 1000 offline selected events per channel Inclusive Hlt2 mu(+track) triggers - Antonio Pérez-Calero

7. Results on muon channels • Output rates and efficiencies for each scenario • Efficiencies definition: Final eff. (Eff. Relative to L0xHLT1) • Work ongoing: • Higher efficiencies seem feasible for muon+track (for equivalent rates), using harder mass cuts, at the cost of biasing inv mass distribution of muon pair in Bd → K*mm. • Low rate muon+track for Bs → mm with strong mass cuts • Hlt2 muon+track lifetime unbiased for Jpsi channels also under study Inclusive Hlt2 mu(+track) triggers - Antonio Pérez-Calero

8. Global results for inclusive muon triggers Consider two rates scenarios per inc. trigger (except for the biased dimuon, which has lower rates) • Rates and final eff. per line • Rate, final eff. and eff. To L0xHLT1 for the OR of all inclusive muon triggers • Note B purity quoted for filtered MinBias events • High rates • Mid rates Inclusive Hlt2 mu(+track) triggers - Antonio Pérez-Calero

9. Global results for inclusive muon triggers • Unbiased dimuon works almost as good at half the rate, providing most of eff. for both Bs→J/y. selections. • But single muon and muon+track at higher rate add robustness in all channels and higher efficiency on Bd→K*mm. • High rates • Mid rates Inclusive Hlt2 mu(+track) triggers - Antonio Pérez-Calero

10. B→HH TIS • Hlt2 Inclusive muon lines also trigger (TIS) hadronic channels. • Useful for extraction of trigger efficiencies • Example, B→HH control channel for Bs→mm. (8k selected B→Kpi ) Inclusive Hlt2 mu(+track) triggers - Antonio Pérez-Calero

11. Summary & TODO’s • Presented description and status of single muon and muon+track inc. selections in two rate scenarios using cuts on robust variables (“HLT2 A” style) • Results obtained with new L0xHlt1 settings: muon +track can provide higher eff than single muon at the same rate (expected) • Two rate rates scenarios considered for global performance of HLT2 inclusive muon lines: • first probably only feasible if considered as a first stage of filtering (“HLT2 A”), and then Kalman fit plus “HLT2 B” (or pre-scaled) • second with almost same results except for Bd →K*mm TO DO: • Additional muon+track lines under study to help when used on their “proper channels” (high mass for Bs→mm and unbiased for Bs→J/yf) • Try both strategies: “Hlt2A” at mid to low rate (robust and faster) and “Hlt2 A+B” (higher eff) • For both cases, start with single muon and muon+track at higher rates than dimuons Inclusive Hlt2 mu(+track) triggers - Antonio Pérez-Calero