some d0 meeting november 2003 muon isolation studies ken johns university of arizona

Some D0 MeetingNovember 2003

Muon Isolation Studies

Ken JohnsUniversity of Arizona

Some D0 MeetingNovember 2003

Conclusions

Isolation variables depend on event topology Z vs Zj vs Zjj Assumes Zj and Zjj samples are relatively pure

Current isolation criteria is inefficient dR and Halo11/Pt(muon) better?

Matrix method in progress Have signal efficiencies but need additional

background events for background efficiencies Apply to events outside Z mass region to

estimate signal and background

Some D0 MeetingNovember 2003

Z, Zj, Zjj Data

Sample Emily Z skim (2 muons, 1 loose, 1 matched

track, other cuts?) Cuts

Good vertex 2 muons with PT > 15 GeV/c 1 isolated muon Same vertex Muon phi (highest PT) – metphi < 165

degrees 75 < dimu mass < 105 GeV/c2

0, 1, >1 jets with ET > 20 GeV

Some D0 MeetingNovember 2003

Z, Zj, Zjj Data

Plots are for isolation variables for the second muon (no isolation requirement) Trkpt Halo11 DCA dR to closest jet dedx Trkdr Rat11 == Halo11 / Pt(muon)

Some D0 MeetingNovember 2003

Z Data (Halo 11)

Some D0 MeetingNovember 2003

Zj Data (Halo 11)

Some D0 MeetingNovember 2003

Zjj Data (Halo 11)

Some D0 MeetingNovember 2003

Z Data (TrkPt)

Some D0 MeetingNovember 2003

Zj Data (TrkPt)

Some D0 MeetingNovember 2003

Zjj Data (TrkPt)

Some D0 MeetingNovember 2003

Zjj Data (Rat11)

Some D0 MeetingNovember 2003

ttmumu MC (Halo 11)

Some D0 MeetingNovember 2003

ttmumu MC (TrkPt)

Some D0 MeetingNovember 2003

ttmumu MC (dR)

Some D0 MeetingNovember 2003

ttmumu MC (Rat11)

Some D0 MeetingNovember 2003

Zjj Data (Emily skim)

Cut Passing

Old isolation loose 33

Old isolation tight 17

New isolation loose(dR > 0.2 and Rat11 < 0.35)

29

New isolation tight 28

New isolation loose (no dR)

37

New isolation tight (no dR)

35

Some D0 MeetingNovember 2003

Zjj Data (dimu skim)

Cut Passing

Old isolation loose 65

Old isolation tight 44

New isolation loose 76

New isolation tight 61

New isolation loose (no dR)

85

New isolation tight (no dR)

76

Some D0 MeetingNovember 2003

bb Data (like sign)

Cut Passing

Old isolation loose 0

Old isolation tight 0

New isolation loose 0

New isolation tight 0

New isolation loose (no dR)

10

New isolation tight (no dR)

1

Some D0 MeetingNovember 2003

bb Data (unlike sign)

Cut Passing

Old isolation loose 3

Old isolation tight 0

New isolation loose 1

New isolation tight 0

New isolation loose (no dR)

12

New isolation tight (no dR)

4

Some D0 MeetingNovember 2003

Z, Zj, Zjj Data

Sample Dimu skims Cuts

Good vertex 2 muons with PT > 15 GeV/c 1 isolated muon Same vertex Muon phi (highest PT) – metphi < 165

degrees 75 < dimu mass < 105 GeV/c2

0, 1, >1 jets with ET > 20 GeV

Some D0 MeetingNovember 2003

bb Data

Sample Dimu skims

Good vertex 2 muons with PT > 10 GeV/c 2 jets with ET > 20 GeV Each muon is within dR < 0.5 of a jet Same vertex Muon phi (highest PT) – metphi < 165

degrees 50 < dimu mass < 120 GeV/c2

Sometimes only like sign muons are required

Some D0 MeetingNovember 2003

Zjj Data (dR)

Some D0 MeetingNovember 2003

Zj Data (dR)

Some D0 MeetingNovember 2003

Z Data (DCA)

Some D0 MeetingNovember 2003

Zj Data (DCA)

Some D0 MeetingNovember 2003

Zjj Data (DCA)

Some D0 MeetingNovember 2003

b-bbar Data (Halo 11)

Some D0 MeetingNovember 2003

b-bbar Data (TrkPt)

Some D0 MeetingNovember 2003

b-bbar Data (Rat11)

Some D0 MeetingNovember 2003

Zjj MC (Halo 11)

Some D0 MeetingNovember 2003

Zjj MC (TrkPt)

Some D0 MeetingNovember 2003

Zjj MC (dR)

Some D0 MeetingNovember 2003

Zjj MC (Rat11)