1. Some D0 Meeting November 2003 Muon Isolation Studies Ken Johns University of Arizona

2. Some D0 Meeting November 2003 Conclusions Isolation variables depend on event topology u Z vs Zj vs Zjj u Assumes Zj and Zjj samples are relatively pure  Current isolation criteria is inefficient u dR and Halo11/Pt(muon) better?  Matrix method in progress u Have signal efficiencies but need additional background events for background efficiencies u Apply to events outside Z mass region to estimate signal and background

3. Some D0 Meeting November 2003 Z, Zj, Zjj Data  Sample u Emily Z skim (2 muons, 1 loose, 1 matched track, other cuts?) u Cuts  Good vertex  2 muons with P T > 15 GeV/c  1 isolated muon  Same vertex  Muon phi (highest P T ) – metphi < 165 degrees  75 < dimu mass < 105 GeV/c 2  0, 1, >1 jets with E T > 20 GeV

4. Some D0 Meeting November 2003 Z, Zj, Zjj Data  Plots are for isolation variables for the second muon (no isolation requirement) u Trkpt u Halo11 u DCA u dR to closest jet u dedx u Trkdr u Rat11 == Halo11 / Pt(muon)

5. Some D0 Meeting November 2003 Z Data (Halo 11)

6. Some D0 Meeting November 2003 Zj Data (Halo 11)

7. Some D0 Meeting November 2003 Zjj Data (Halo 11)

8. Some D0 Meeting November 2003 Z Data (TrkPt)

9. Some D0 Meeting November 2003 Zj Data (TrkPt)

10. Some D0 Meeting November 2003 Zjj Data (TrkPt)

11. Some D0 Meeting November 2003 Zjj Data (Rat11)

12. Some D0 Meeting November 2003 ttmumu MC (Halo 11)

13. Some D0 Meeting November 2003 ttmumu MC (TrkPt)

14. Some D0 Meeting November 2003 ttmumu MC (dR)

15. Some D0 Meeting November 2003 ttmumu MC (Rat11)

16. Some D0 Meeting November 2003 Zjj Data (Emily skim) CutPassing Old isolation loose33 Old isolation tight17 New isolation loose (dR > 0.2 and Rat11 < 0.35) 29 New isolation tight28 New isolation loose (no dR)37 New isolation tight (no dR)35

17. Some D0 Meeting November 2003 Zjj Data (dimu skim) CutPassing Old isolation loose65 Old isolation tight44 New isolation loose76 New isolation tight61 New isolation loose (no dR)85 New isolation tight (no dR)76

18. Some D0 Meeting November 2003 bb Data (like sign) CutPassing Old isolation loose0 Old isolation tight0 New isolation loose0 New isolation tight0 New isolation loose (no dR)10 New isolation tight (no dR)1

19. Some D0 Meeting November 2003 bb Data (unlike sign) CutPassing Old isolation loose3 Old isolation tight0 New isolation loose1 New isolation tight0 New isolation loose (no dR)12 New isolation tight (no dR)4

20. Some D0 Meeting November 2003 Z, Zj, Zjj Data  Sample u Dimu skims u Cuts  Good vertex  2 muons with P T > 15 GeV/c  1 isolated muon  Same vertex  Muon phi (highest P T ) – metphi < 165 degrees  75 < dimu mass < 105 GeV/c 2  0, 1, >1 jets with E T > 20 GeV

21. Some D0 Meeting November 2003 bb Data  Sample u Dimu skims  Good vertex  2 muons with P T > 10 GeV/c  2 jets with E T > 20 GeV  Each muon is within dR < 0.5 of a jet  Same vertex  Muon phi (highest P T ) – metphi < 165 degrees  50 < dimu mass < 120 GeV/c 2  Sometimes only like sign muons are required

22. Some D0 Meeting November 2003 Zjj Data (dR)

23. Some D0 Meeting November 2003 Zj Data (dR)

24. Some D0 Meeting November 2003 Z Data (DCA)

25. Some D0 Meeting November 2003 Zj Data (DCA)

26. Some D0 Meeting November 2003 Zjj Data (DCA)

27. Some D0 Meeting November 2003 b-bbar Data (Halo 11)

28. Some D0 Meeting November 2003 b-bbar Data (TrkPt)

29. Some D0 Meeting November 2003 b-bbar Data (Rat11)

30. Some D0 Meeting November 2003 Zjj MC (Halo 11)

31. Some D0 Meeting November 2003 Zjj MC (TrkPt)

32. Some D0 Meeting November 2003 Zjj MC (dR)

33. Some D0 Meeting November 2003 Zjj MC (Rat11)