23 |
|
The data yields in the |
24 |
|
four regions are summarized in Table~\ref{tab:datayield}. |
25 |
|
The prediction of the ABCD method is is given by $A\times C/B$ and |
26 |
< |
is 1.5 events. (see Table~\ref{tab:datayield}. |
26 |
> |
is 1.5 $\pm$ 0.9 events (statistical uncertainty only, assuming |
27 |
> |
Gaussian errors). (see Table~\ref{tab:datayield}). |
28 |
|
|
29 |
|
\begin{table}[hbt] |
30 |
|
\begin{center} |
60 |
|
%estimate of the $t\bar{t}$ contribution. The result |
61 |
|
%of this exercise is {\color{red} xx} events. |
62 |
|
|
63 |
+ |
\clearpage |
64 |
+ |
|
65 |
|
\subsection{Background estimate from the $P_T(\ell\ell)$ method} |
66 |
|
\label{sec:victoryres} |
67 |
|
|
68 |
+ |
We first use the $P_T(\ell \ell)$ method to predict the number of events |
69 |
+ |
in control region A, defined in Sec.~\ref{sec:abcd} as |
70 |
+ |
$125<{\rm SumJetPt}>300$~GeV and $\met/\sqrt{\rm SumJetPt}>$8.5. |
71 |
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We count the number of events in region |
72 |
+ |
$A'$, defined in Sec.~\ref{sec:othBG} by replacing the above $\met/\sqrt{\rm SumJetPt}$ |
73 |
+ |
cut with the same cut on the quantity $P_T(\ell\ell)/\sqrt{\rm SumJetPt}$, |
74 |
+ |
and find $N_{A'}=6$. To predict the yield in region A we take |
75 |
+ |
$N_A = K \cdot K_C \cdot N_{A'} = 10.4 \pm 4.2$ |
76 |
+ |
(statistical uncertainty only, assuming Gaussian errors), |
77 |
+ |
where we have taken $K = 1.73$ and $K_C = 1$. This yield is in good |
78 |
+ |
agreement with the observed yield of 11 events, as shown in |
79 |
+ |
Table~\ref{tab:victory_control} and displayed in Fig.~\ref{fig:victory} (left). |
80 |
+ |
{\color{red} \bf Perform DY estimate for this control region}. |
81 |
+ |
|
82 |
+ |
Encouraged by the good agreement between predicted and observed yields |
83 |
+ |
in the control region, we proceed to perform the $P_T(\ell \ell)$ method |
84 |
+ |
in the signal region ${\rm SumJetPt}>300$~GeV. |
85 |
|
The number of data events in region $D'$, which is defined in |
86 |
|
Section~\ref{sec:othBG} to be the same as region $D$ but with the |
87 |
|
$\met/\sqrt{\rm SumJetPt}$ requirement |
88 |
< |
replaced by a $P_T(\ell\ell)/\sqrt{\rm SumJetPt}$ requirement |
88 |
> |
replaced by a $P_T(\ell\ell)/\sqrt{\rm SumJetPt}$ requirement, |
89 |
|
is $N_{D'}=2$. Thus the BG prediction is |
90 |
< |
$N_D = K \cdot K_C \cdot N_{D'} = 1.5$ |
91 |
< |
where $K=1.5 \pm xx$ as derived in Sec.~\ref{sec:victory} and |
92 |
< |
$K_C = 1$. |
93 |
< |
Note that if we were to subtract off from region $D'$ |
94 |
< |
the {\color{red} 0.8 $\pm$ 0.8} DY events estimated from |
95 |
< |
Section~\ref{sec:othBG}, the background |
96 |
< |
prediction would change to $N_D=1.8 \pm xx$ events. |
97 |
< |
|
98 |
< |
%%%TO BE REPLACED |
79 |
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%{\color{red}As mentioned previously, for the 11/pb analysis |
80 |
< |
%we use the $K$ factor from data and take $K=1$. |
81 |
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%This will change for the full dataset. We will also pay |
82 |
< |
%more attention to the statistical errors.} |
83 |
< |
|
84 |
< |
%The number of data events in region $D'$, which is defined in |
85 |
< |
%Section~\ref{sec:othBG} to be the same as region $D$ but with the |
86 |
< |
%$\met/\sqrt{\rm SumJetPt}$ requirement |
87 |
< |
%replaced by a $P_T(\ell\ell)/\sqrt{\rm SumJetPt}$ requirement |
88 |
< |
%is $N_{D'}=1$. Thus the BG prediction is |
89 |
< |
%$N_D = K \cdot K_{\rm fudge} \cdot N_{D'} = 1.5$ |
90 |
< |
%where we used $K=1.5 \pm xx$ and $K_{\rm fudge}=1.0 \pm 0.0$. |
91 |
< |
%Note that if we were to subtract off from region $D'$ |
92 |
< |
%the {\color{red} 0.4 $\pm$ 0.4} DY events estimated from |
93 |
< |
%Section~\ref{sec:othBG}, the background |
94 |
< |
%prediction would change to $N_D=0.9 \pm xx$ events. |
95 |
< |
%{\color{red} When we do this with a real |
96 |
< |
%$K_{\rm fudge}$, the fudge factor will be different |
97 |
< |
%after the DY subtraction.} |
98 |
< |
|
99 |
< |
As a cross-check, we use the $P_T(\ell \ell)$ |
100 |
< |
method to also predict the number of events in the |
101 |
< |
control region $125<{\rm SumJetPt}<300$ GeV and |
102 |
< |
\met/$\sqrt{\rm SumJetPt} > 8.5$. We predict |
103 |
< |
$5.6^{+x}_{-y}$ events and we observe 4. |
104 |
< |
The results of the $P_T(\ell\ell)$ method are |
105 |
< |
summarized in Figure~\ref{fig:victory}. |
90 |
> |
$N_D = K \cdot K_C \cdot N_{D'} = 3.07 \pm 2.17$ where $K=1.54 \pm xx$ |
91 |
> |
as derived in Sec.~\ref{sec:victory} and $K_C = 1$. |
92 |
> |
We next subtract off the expected DY contribution of |
93 |
> |
{\color{red} \bf 0.8 $\pm$ 0.8 (update DY estimate)} events, as calculated |
94 |
> |
in Sec.~\ref{sec:othBG}. This gives a predicted yield of |
95 |
> |
$N_D=1.8^{+2.5}_{-1.8}$ events, which is consistent with the observed yield of |
96 |
> |
1 event, as summarized in Table~\ref{tab:victory_signal} and Fig.~\ref{fig:victory} |
97 |
> |
(right). |
98 |
> |
|
99 |
|
|
100 |
|
\begin{figure}[hbt] |
101 |
|
\begin{center} |
110 |
|
\end{figure} |
111 |
|
|
112 |
|
|
113 |
+ |
\begin{table}[hbt] |
114 |
+ |
\begin{center} |
115 |
+ |
\label{tab:victory_control} |
116 |
+ |
\caption{Results of the dilepton $p_{T}$ template method in the control region |
117 |
+ |
$125 < \mathrm{sumJetPt} < 300$~GeV. The predicted and observed yields for |
118 |
+ |
the region $\mathrm{tcmet}/\sqrt{\mathrm{sumJetPt}}>$~8.5 are shown for data |
119 |
+ |
and MC. The error on the prediction for data is statistical only, assuming |
120 |
+ |
Gaussian errors.} |
121 |
+ |
\begin{tabular}{l|c|c|c} |
122 |
+ |
\hline |
123 |
+ |
& Predicted & Observed & Obs/Pred \\ |
124 |
+ |
\hline |
125 |
+ |
total SM MC & 7.10 & 8.61 & 1.21 \\ |
126 |
+ |
data & 10.38 $\pm$ 4.24 & 11 & 1.06 \\ |
127 |
+ |
\hline |
128 |
+ |
\end{tabular} |
129 |
+ |
\end{center} |
130 |
+ |
\end{table} |
131 |
+ |
|
132 |
+ |
\begin{table}[hbt] |
133 |
+ |
\begin{center} |
134 |
+ |
\label{tab:victory_signal} |
135 |
+ |
\caption{Results of the dilepton $p_{T}$ template method in the signal region |
136 |
+ |
$125 < \mathrm{sumJetPt} < 300$~GeV. The predicted and observed yields for |
137 |
+ |
the region $\mathrm{tcmet}/\sqrt{\mathrm{sumJetPt}}>$~8.5 are shown for data |
138 |
+ |
and MC. The error on the prediction for data is statistical only, assuming |
139 |
+ |
Gaussian errors.} |
140 |
+ |
\begin{tabular}{l|c|c|c} |
141 |
+ |
\hline |
142 |
+ |
& Predicted & Observed & Obs/Pred \\ |
143 |
+ |
\hline |
144 |
+ |
total SM MC & 0.96 & 1.41 & 1.46 \\ |
145 |
+ |
data & $1.8^{+2.5}_{-1.8}$ & 1 & 0.56 \\ |
146 |
+ |
\hline |
147 |
+ |
\end{tabular} |
148 |
+ |
\end{center} |
149 |
+ |
\end{table} |
150 |
+ |
|
151 |
+ |
|
152 |
|
\subsection{Summary of results} |
153 |
|
To summarize: we see no evidence for an anomalous |
154 |
|
rate of opposite sign isolated dilepton events |