Baosen Chen, Xin Chen, Mousumi Datta,

1
BR Measurement of B0?D-pp?, D-pp?, D0pp, D0pp
Decays

• Baosen Chen, Xin Chen, Mousumi Datta,
• Haibo Li, Bruce Mellado and Sau Lan Wu
• University of Wisconsin-Madison
• May 24,2004

2
Reconstruction Modes

• Signal MC
• B0-gtD-pp?, D--gtD0?-, D0-gtK-?,K-??-?,K-??0
• B0-gtD-pp?, D--gtK?-?-
• B0-gtD0pp, D0-gtD0?0, D0-gtK?-
• B0-gtD0pp, D0-gtK?-
• Bkg MC
• 1. B0B0 357.2 fb-1
• 2. BB- 349.7 fb-1
• 3. cc 128.0 fb-1
• 4. uds 100.7 fb-1
• Data
• 112.5 fb-1 of data taken during run 1-3

3
Pre-Selection

• Both Proton and anti-proton from pLhVeryLoose
• K (from D) from KMicroNotPion
• ? from GoodTracksVeryLoose
• ?0 from Pi0AllDefault
• ? (from B) from ChargeTracks
• D0 and D? mass window (charged modes) 40 MeV
• MESgt5.2 GeV and ?Elt0.4 GeV
• Vertex convergence for B0, D0 and D- candidates

4
Fit Model

• Nsigx(1-fscf)xPtru(mES, ?E) fscfxPscf(mES,
  ?E) NbkgxPbkg(mES, ?E)
• Nsig number of signal events
• Nbkg number of bkg events
• Pxxx PDFs of mES and ?E
• fscf Self-Cross-Feed(untruth-macthed signal)
  fraction

5
B0?D-pp?,D-?D0?-,D0 ?K-?
Channel 1

• Beta level eff is 19.55
• Pion IDfail KMicroVeryTight PidLHElectrons,
  muMicroVeryTight, pLhVeryTight
• Kaon ID pass KMicroTight
• p and p ID pass pLhTight
• D0 vertex probability gt 0.001 and B0 vertex gt 0.0
• 1.844 lt mass of D0 lt1.884
• deltaM lt 0.148
• ?Elt0.08, 5.23ltMESlt5.29 GeV
• -0.9ltCos(?TB)lt0.9
• R2alllt0.35
• Final signal eff is 6.22

6
Signal MC
SCF fraction is 19.11
7
Background MC
8
Signal Parameterization
9
Fit Result
10
Fit Result (Cont)
11
B0?D-pp?,D-?D0?-,D0 ?K-??-?
Channel 1

• Beta level eff is 6.55
• Pion IDfail KMicroVeryTight PidLHElectrons,
  muMicroVeryTight, pLhVeryTight
• Kaon ID pass KMicroTight
• p and p ID pass pLhTight
• D0 vertex probability gt 0.001 and B0 vertex gt 0.0
• 1.848 lt mass of D0 lt1.880
• deltaM lt 0.149
• ?Elt0.08, 5.23ltMESlt5.29 GeV
• -0.9ltCos(?TB)lt0.9
• R2alllt0.35
• Final signal eff is 0.81

12
Signal MC
SCF fraction is 21.72
13
Background MC
14
Signal Parameterization
15
Fit Result
16
Fit Result (Cont)
17
B0?D-pp?,D-?D0?-,D0 ?K-??0
Channel 1

• Beta level eff is 11.94
• Pion IDfail KMicroVeryTight PidLHElectrons,
  muMicroVeryTight, pLhVeryTight
• Kaon ID pass KMicroTight
• p and p ID pass pLhTight
• 0.01 lt photon LAT lt0.6
• Photon energy gt 50MeV
• 0.12 lt mass of ?0 lt 0.15
• D0 vertex probability gt 0.001 and B0 vertex gt 0.0
• 1.835 lt mass of D0 lt1.894
• deltaM lt 0.1485
• ?Elt0.08, 5.23ltMESlt5.29 GeV
• -0.9ltCos(?TB)lt0.9
• R2alllt0.35
• Final signal eff is 1.18

18
Signal MC
SCF fraction is 33.80
19
Background MC
20
Signal Parameterization
21
Fit Result
22
Fit Result (Cont)
Three modes combined
23
B0?D-pp?,D-?K?-?-
Channel 2

• Beta level eff is 20.59
• Pion IDfail KMicroVeryTight PidLHElectrons,
  muMicroVeryTight, pLhVeryTight
• Kaon ID pass KMicroTight
• p and p ID pass pLhTight
• D- vertex probability gt 0.001 and B0 vertex gt 0.0
• 1.853 lt Mass of D- lt1.88
• ?Elt0.08, 5.23ltMESlt5.29 GeV
• -0.9ltCos(?TB)lt0.8
• R2alllt0.35
• Final signal eff is 4.77

24
Signal MC
SCF fraction is 19.48
25
Background MC
26
Signal Parameterization
27
Fit Result
28
Fit Result (Cont)
29
B0?D0pp,D0?D0?0,D0 ?K?-
Channel 3

• Beta level eff is 26.95
• Pion IDfail KMicroVeryTight PidLHElectrons,
  muMicroVeryTight, pLhVeryTight
• Kaon ID pass KMicroLoose
• p and p ID pass pLhTight
• 0.1155 lt mass of ?0 lt 0.135
• D0 vertex probability gt 0.0 and B0 vertex gt 0.0
• 1.845 lt mass of D0 lt 1.884
• 0.135 lt deltaM lt 0.15
• ?Elt0.08, 5.23ltMESlt5.29 GeV
• -0.9ltCos(?TB)lt0.9
• R2alllt0.35
• Final signal eff is 6.72

30
Signal MC
SCF fraction is 46.60
31
Background MC
32
Signal Parameterization
33
Fit Result
34
Fit Result (Cont)
35
B0?D0pp,D0 ?K?-
Channel 4

• Beta level eff is 37.39
• Pion IDfail KMicroVeryTight PidLHElectrons,
  muMicroVeryTight, pLhVeryTight
• Kaon ID pass KMicroTight
• p and p ID pass pLhTight
• 0.1155 lt mass of ?0 lt 0.135
• D0 vertex probability gt 0.001 and B0 vertex gt 0.0
• 1.844 lt mass of D0 lt 1.885
• ?Elt0.08, 5.23ltMESlt5.29 GeV
• -0.9ltCos(?TB)lt0.9
• R2alllt0.35
• Final signal eff is 15.78

36
Signal MC
SCF fraction is 3.37
37
Background MC
38
Signal Parameterization
39
Fit Result
40
Fit Result (Cont)
41
Summary