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Comparing UserCode/benhoob/cmsnotes/StopSearch/eventsel.tex (file contents):
Revision 1.2 by vimartin, Fri Jun 29 15:12:32 2012 UTC vs.
Revision 1.3 by benhoob, Fri Jun 29 18:23:24 2012 UTC

# Line 8 | Line 8 | The preselection sample is based on the
8    \begin{itemize}
9    \item $\pt>30~\GeVc$ and $|\eta|<2.5(2.1)$ for \E(\M)
10    \item satisfy the identification and isolation requirements detailed
11 <    in~\cite{ref:osznote} for electrons and in~\cite{ref:osznote} for muons
11 >    in the same-sign SUSY analysis (SUS-11-010) for electrons and the opposite-sign
12 >    SUSY analysis (SUS-11-011) for muons
13    \end{itemize}
14    \item require at least 4 PF jets in the event with $\pt>30~\GeV$
15      within $|\eta|<2.5$, out of which at least 1 is b-tagged based on
16 <    the SSV medium working point [CITE].
16 >    the SSV medium working point.
17    \item require moderate $\met>50~\GeV$
18   \end{itemize}
19  
20 < A benchmark signal sample is selected by tightening the \met\ and
20 > Currently, we focus on the muon channel because it is cleaner (the QCD contribution is negligible)
21 > and the triggers are simpler (we use single muon triggers, as opposed to electron + 3-jet triggers).
22 > We will add the electron channel, time permitting. However, since this is a systematics-dominated
23 > analysis, increasing the statistics by adding the electrons is not expected to significantly improve
24 > the sensitivity, especialy because the electron selection efficiency is smaller and the systematic
25 > uncertainty associated with the QCD background is larger.
26 >
27 > A benchmark signal region is selected by tightening the \met\ and
28   adding an \mt\ requirement
29   \begin{itemize}
30   \item $\met>100~\GeV$
31   \item $\mt>150~\GeV$
32   \end{itemize}
33  
34 + {\bf We have not looked at the data in the signal region after the first 1 fb$^{-1}$ of data.}
35 +
36   \subsection{Corrections to Jets and \met}
37  
38   The official recommendations from the Jet/MET group are used for
# Line 33 | Line 43 | based on the global tags GR\_R\_42\_V23
43   data (MC). In addition, these jet energy corrections are propagated to
44   the \met\ calculation, following the official prescription for
45   deriving the Type I corrections. It may be noted that events with
46 < anomalous corrections are excluded from the sample since these
46 > anomalous ``rho'' pile-up corrections are excluded from the sample since these
47   correspond to events with unphysically large \met\ and \mt\ tail
48 < signal region. An additional correction to remove
48 > signal region (see Figure~\ref{fig:mtrhocomp}). An additional correction to remove
49   the $\phi$-modulation observed in the \met\ is included, improving
50   the agreement between the data and the MC, as shown in
51 < Figure.~\ref{fig:metphicomp}. This correction has an effect on this analysis,
51 > Figure~\ref{fig:metphicomp}. This correction has an effect on this analysis,
52   since the azimuthal angle enters the \mt\ distribution.
53  
54 < \begin{figure}[tbh]
54 > \clearpage
55 >
56 > \begin{figure}[!ht]
57    \begin{center}
58          \includegraphics[width=0.5\linewidth]{plots/mt_rho_comp.png}
59          \caption{ \label{fig:mtrhocomp}%\protect
# Line 56 | Line 68 | since the azimuthal angle enters the \mt
68    \end{center}
69   \end{figure}
70  
71 < \begin{figure}[hb]
71 > \begin{figure}[!hb]
72    \begin{center}
73          \includegraphics[width=0.5\linewidth]{plots/metphi.pdf}%
74          \includegraphics[width=0.5\linewidth]{plots/metphi_phicorr.pdf}
# Line 67 | Line 79 | since the azimuthal angle enters the \mt
79    \end{center}
80   \end{figure}
81  
82 + \clearpage
83 +
84   \subsection{Branching Fraction Correction}
85  
86   The leptonic branching fraction used in some of the \ttbar\ MC samples
87 < differs from the value listed in the PDG $(10.80 ± 0.09)\%$.
87 > differs from the value listed in the PDG $(10.80 \pm 0.09)\%$.
88   Table.~\ref{tab:wlepbf} summarizes the branching fractions used in
89   the generation of the various \ttbar\ MC samples.
90   For \ttbar\ samples with the incorrect leptonic branching fraction, event

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