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# Line 23 | Line 23 | expectation is 1.4 events.
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}
# Line 59 | Line 60 | $W^{\pm}$ + jets   &           0.00   &
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 + 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 < %{\color{red}As mentioned previously, for the 11/pb analysis
80 < %we use the $K$ factor from data and take $K=1$.
81 < %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}
# Line 117 | Line 110 | ${P_T(\ell\ell)}/\sqrt{\rm SumJetPt}$ in
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

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