Skip to content

B2Jpsih_B2Jpsihh_noMuonIDCut

Mengzhen Wang requested to merge mengzhen_b2Jpsih_b2Jpsihh_noMuonID into master

This MR is for B->Jpsi K, B->Jpsi K pi, Bs->Jpsi phi selection lines with no Muon-station based MuonID cut. RICH-based MuonID cuts are still used.

Target on turbo stream. We need only the signal tracks and do not need persistReco.

If a peak is visible, we can use it to tag the muon performance when doing the Jpsi->MuMu Xsec study using early 2024 data (a first-order check of potential correlation between tag and probe in traditional muon-id calibration method). Should be promising to see the peak: rate a bit higher than the standard B2Jpsip line, but not too crazy; and efficiency is lower only with a factor of 30%.

MC samples for eff test:

sim+std://MC/Dev/Beam6800GeV-expected-2024-MagDown-Nu7.6-25ns-Pythia8/Sim10c/12143001/DIGI   (B2JpsiK)
sim+std://MC/Dev/Beam6800GeV-expected-2024-MagDown-Nu7.6-25ns-Pythia8/Sim10c/11144002/DIGI (B2JpsiKstar)
sim+std://MC/Dev/Beam6800GeV-expected-2024-MagDown-Nu7.6-25ns-Pythia8/Sim10c/13144011/DIGI (Bs2Jpsiphi)

Rate looks fine. Tested using 100000 events in mdf files at /eos/lhcb/wg/rta/WP3/bandwidth_division/Beam6800GeV-expected-2024-MagDown-nu7.6/hlt1_filtered/30000000. Use the current_without_UT configuration for hlt2 configuration.

--------------------------------------------------------------------------------------------------------------
Line:    Hlt2BandQ_Bp2JpsiKp_NoMuonIDDecision            Incl: 0.0342 +/- 0.0197 kHz,   Excl: 0.0342 +/- 0.0197 kHz
Line:    Hlt2BandQ_Bs2JpsiKpKm_NoMuonIDDecision          Incl: 0.0 +/- 0.0 kHz, Excl: 0.0 +/- 0.0 kHz
Line:    Hlt2BandQ_Bs2JpsiPhi_NoMuonIDDecision (disabled)          Incl: 0.0 +/- 0.0 kHz, Excl: 0.0 +/- 0.0 kHz
Line:    Hlt2BandQ_Bz2JpsiKpPim_NoMuonIDDecision         Incl: 0.0342 +/- 0.0197 kHz,   Excl: 0.0342 +/- 0.0197 kHz
Line:    Hlt2BandQ_Bz2JpsiKst_NoMuonIDDecision (disabled)          Incl: 0.0 +/- 0.0 kHz, Excl: 0.0 +/- 0.0 kHz

--------------------------------------------------------------------------------------------------------------

Rate of the standard B2JpsiK line as reference:

Line:    Hlt2BandQ_BpToJpsiKp_JpsiToMuMuDecision         Incl: 0.0114 +/- 0.0113 kHz,   Excl: 0.0114 +/- 0.0113 kHz

Hlt2BandQ_Bs2JpsiPhi_NoMuonIDDecision is a subsample of Hlt2BandQ_Bs2JpsiKpKm_NoMuonIDDecision, Hlt2BandQ_Bz2JpsiKst_NoMuonIDDecision is a subsample of Hlt2BandQ_Bz2JpsiKpPim_NoMuonIDDecision. Will keep only one in each group. Now the rate looks fine, will keep the full m(KPi) m(KK) spectrum lines. Other two kept as back-up choice if we need to reduce the rate.

For eff estimation I assume 100% hlt1 efficiency. See https://indico.cern.ch/event/1332271/contributions/5710654/attachments/2778230/4842174/HLT1_BW_Division_LHCb_UK_Update.pdf for N(hlt1)/Ntot. We have tight kinematic cuts in Hlt2, so the N(hlt1+hlt2)/N(hlt2) eff will be higher than N(hlt1)/Ntot.

Efficiency of B2JpsiK (with UT in Reco): 1129/5614 = 20%. The withMuonID line has eff = 1575/5614 = 28%. Similar values obtained if using current_without_UT configuration.

Efficiency of Bz2JpsiKpPim_NoMuonID line: 460/5611. = 8%

Efficiency of Bs2JpsiKpKm_NoMuonID line: 362./5373 = 7%

c.c. to Run3 Jpsi->MuMu team : @gcavalle @lan @zexu @cdong @squ @jialu

Edited by Mengzhen Wang

Merge request reports