Violation in Mixing

7.7 The maximum likelihood analysis 179
Events / 0.0022375 GeV/c 2
600
500
400
300
200
100
38.32 / 33
P1 89.69 2.623
P2 1482. 40.70
P3 5.280 0.
P4 0.2624E-02 0.6195E-04
0
5.2 5.22 5.24 5.26 5.28 5.3
Energy substituted mass dataset:mes
Nent = 11938
400
Mean = 5.24
RMS = 0.02419
350
300
250
200
150
100
50
c = -21.09 ± 1.02
Energy substituted mass (GeV/c 2)
0
5.2 5.21 5.22 5.23 5.24 5.25 5.26 5.27 5.28
Events / 0.0022375 GeV/c 2
250
200
150
100
50
47.27 / 32
P1 21.61 1.292
P2 655.4 26.45
P3 5.280 0.
P4 0.2609E-02 0.8669E-04
0
5.2 5.22 5.24 5.26 5.28 5.3
mES pi+
Energy substituted mass dataset:mes
Nent = 5963
Mean = 5.24
200
RMS = 0.02426
180
160
140
120
100
80
60
40
20
c = -20.93 ± 1.44
Energy substituted mass (GeV/c 2)
0
5.2 5.21 5.22 5.23 5.24 5.25 5.26 5.27 5.28
Figure 7-5. Top plots: distributions of Ñ�Ë for � � � � decays in Run 1 (left) and Run 2 (right).
Bottom plots: distributions of Ñ�Ë for Run 1 (left) and Run 2 (right) on-resonance data in the region � �
�¡�� � �� ��Î.
The signal Fisher discriminant distribution is obtained from signal � � Monte Carlo and cross-checked
with the � � control sample. After tightening the cut on Ó× �Ë relative to the branching fraction analysis
we find that the signal Fisher shape is a pure Gaussian. Top plots in Fig. 7-7 shows the combined Run 1 + 2
sample and the signal Monte Carlo. We use the latter distribution for both Run 1 and Run 2, with the � �
sample used to estimate the systematic error. The background Fisher shape is the usual double Gaussian
whose parameters are left floating in the fit. Bottom plots in Fig. 7-7 shows the Fisher distribution in the
side-band region. For the background common parameters for the entire dataset are floated in the fit.
The � ��Ö�Ò�ÓÚ angle pulls for pions and kaons are determined in a high-statistics data sample of � £ � � �,
� � � decays, where the same PDFs are used for signal and background. We also use the same
parameterization for positive and negative tracks. The pulls are defined as � � �ÜÔ Ó«×�Ø ��� ,
where � �ÜÔ is the expected angle for a pion or kaon with the given momentum (corrected for energy
loss) and the offsets and resolutions depend on track polar angle. Left plots in Fig. 7-8 show the offset
ANALYSIS OF THE TIME-DEPENDENT �È -VIOLATING ASYMMETRY IN � � � � DECAYS