1. Preliminary Results of D0 Dalitz Plot Analysis
Kalanand Mishra,
G. Mancinelli, Brian Meadows, Mike Sokoloff
University of Cincinnati
Charm AWG, 6/08/06

2. Efficiency-corrected Dalitz plot
~ 4 % bkg
m2(K-π0)
m2(K-K+)
m2(K+π0)

3. CLEO used only K*(892),  and NR terms to fit the data
CLEO Fit (prelim. result presented at FPCP 2006)
CLEO had 600
events with 33 % background
We have 6800
events with 4 % background
CLEO used only K*(892),  and NR terms to fit the data

4. Bgd Dalitz HistPdf taken from the mD sideband
Data Fit with CLEO PDF
Bgd Dalitz HistPdf taken from the mD sideband
1 Nonres_amp e e-02 (5.6 in CLEO results)
2 Nonres_phase e e+00 (220 in CLEO results)
3 K*- amp e e-02
4 K*-_phase e e+00
5  amp e e-02
6  phase e e+00
2 /nDOF =

5. Unlikely to be due to background
There isn’t much background
According to MC, bgd distributions in SR and SB agree
Data and MC agree in the SB

6. Try adding more resonances
(1020)
K*(892)+
K*(892)- NR
K*(1410)+
K(1410)*-
Kappa+
Kappa-
P-wave NR(+)
P-wave NR(-)
P-wave NR(0)
K*0(1430)+
K*0(1430)-

7. Fit with K*,,K*(1410),NR Fit Fractions 2 /nDOF = 1.27373
Phi :
K* :
K* :
Nonres :
1 K*-_amp e e-02
2 K*-_phase e e+00
3 K*1410+_amp e e-01
4 K*1410+_phase e e+00
5 K*1410-_amp e e-01
6 K*1410-_phase e e+00
7 Nonres_amp e e-02
8 Nonres_phase e e+00
9 Phi_amp e e-02
10 Phi_phase e e+00
2 /nDOF =

8. Fit with K*,,Kappa,NR Fit Fractions 2 /nDOF = 1.16075
Phi :
K* :
Kappa- :
Nonres :
1 K*-_amp e e-02
2 K*-_phase e e+00
3 Kappa+_amp e e-02
4 Kappa+_phase e e+00
5 Kappa-_amp e e-02
6 Kappa-_phase e e+00
7 Nonres_amp e e-01
8 Nonres_phase e e+00
9 Phi_amp e e-02
10 Phi_phase e e+00
2 /nDOF =

9. Fit with K*,,Kappa Fit Fractions 2 /nDOF = 1.35428 Kappa+ : 0.15881
Phi :
K* :
Kappa- :
K*(1410)- :
1 K*-_amp e e-02
2 K*-_phase e e+00
3 K*1410+_amp e e-01
4 K*1410+_phase e e+01
5 K*1410-_amp e e-01
6 K*1410-_phase e e+00
7 Kappa+_amp e e-02
8 Kappa+_phase e+02
9 Kappa-_amp e e-02
10 Kappa-_phase e e+00
11 Phi_amp e e-02
12 Phi_phase e e+00
2 /nDOF =

10. Try including p-wave NR
1 K*-_amp e e-02
2 K*-_phase e e+00
3 K*1410+_amp e e-01
4 K*1410+_phase e e+00
5 K*1410-_amp e e-01
6 K*1410-_phase e e+01
7 Kappa+_amp e e-01
8 Kappa+_phase e e+01
9 Kappa-_amp e e-01
10 Kappa-_phase e e+01
11 NRPW_P_amp e e+00
12 NRPW_P_phase e e+01
13 NRPW_M_amp e e+00
14 NRPW_M_phase e e+01
15 NRPW_0_amp e e+00
16 NRPW_0_phase e e+01
17 Nonres_amp e e-01
18 Nonres_phase e e+00
19 Phi_amp e e-02
20 Phi_phase e e+00
Fit Fractions
K* :
K* :
Kappa+ :
P-wave NR+ :
Phi :
P-wave NR0 :
K* :
K* :
Kappa- :
P-wave NR- :
Nonres :
2 /nDOF =

11. Fit with everything (except p-wave NR)
2 /nDOF =

12. Fit with everything
Data
Fit
(Data-Fit)/Poisson

13. Fit results FIT FRACTIONS: 2) K*1410+ : 0.0080731 3) Phi : 0.20659 C
NO. NAME VALUE ERROR
1 K*- amp e e-02
2 K*- phase e e+00
3 K*1410+ amp e e-01
4 K*1410+ phase e e+01
5 K*1410- amp e e-01
6 K*1410- phase e e+00
7 Kappa+ amp e e-01
8 Kappa+ phase e e+00
9 Kappa- amp e e-01
10 Kappa- phase e e+01
11 Nonres amp e e-01
12 Nonres phase e e+00
13 Phi amp e e-02
14 Phi phase e e+01
FIT FRACTIONS:
1) K*+ :
2) K*1410+ :
3) Phi : C
4) K*- :
5) K*1410- :
6) Nonres :
7) Kappa+ :
8) Kappa- :

14. To do Try to continue improving the fit
Fit systematics and the robustness of the fit:
Generate and fit several hundred toy MC samples
Repeat the fit with several independent data sub-samples
Try to fit with different possible combinations of resonances and NR terms
Other suggestions?
Finally, start looking for CP asymmetry