| 3 |
|
The preselection sample is based on the following criteria |
| 4 |
|
\begin{itemize} |
| 5 |
|
\item satisfy the trigger requirement (see |
| 6 |
< |
Table.~\ref{tab:DatasetsData}) |
| 6 |
> |
Table.~\ref{tab:DatasetsData}). Dilepton triggers are used only for the dilepton control region. |
| 7 |
|
\item select events with one high \pt\ electron or muon, requiring |
| 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 |
| 21 |
< |
adding an \mt\ requirement |
| 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\ as well as isolated track veto requirement |
| 29 |
|
\begin{itemize} |
| 30 |
|
\item $\met>100~\GeV$ |
| 31 |
|
\item $\mt>150~\GeV$ |
| 32 |
+ |
\item isolated track veto as discussed below |
| 33 |
|
\end{itemize} |
| 34 |
|
|
| 35 |
+ |
{\bf We have not looked at the data in the signal region after the first 1 fb$^{-1}$ of data.} |
| 36 |
+ |
|
| 37 |
|
\subsection{Corrections to Jets and \met} |
| 38 |
|
|
| 39 |
|
The official recommendations from the Jet/MET group are used for |
| 44 |
|
data (MC). In addition, these jet energy corrections are propagated to |
| 45 |
|
the \met\ calculation, following the official prescription for |
| 46 |
|
deriving the Type I corrections. It may be noted that events with |
| 47 |
< |
anomalous corrections are excluded from the sample since these |
| 47 |
> |
anomalous ``rho'' pile-up corrections are excluded from the sample since these |
| 48 |
|
correspond to events with unphysically large \met\ and \mt\ tail |
| 49 |
< |
signal region. An additional correction to remove |
| 49 |
> |
signal region (see Figure~\ref{fig:mtrhocomp}). An additional correction to remove |
| 50 |
|
the $\phi$-modulation observed in the \met\ is included, improving |
| 51 |
|
the agreement between the data and the MC, as shown in |
| 52 |
< |
Figure.~\ref{fig:metphicomp}. This correction has an effect on this analysis, |
| 52 |
> |
Figure~\ref{fig:metphicomp}. This correction has an effect on this analysis, |
| 53 |
|
since the azimuthal angle enters the \mt\ distribution. |
| 54 |
|
|
| 55 |
< |
\begin{figure}[tbh] |
| 55 |
> |
\clearpage |
| 56 |
> |
|
| 57 |
> |
\begin{figure}[!ht] |
| 58 |
|
\begin{center} |
| 59 |
|
\includegraphics[width=0.5\linewidth]{plots/mt_rho_comp.png} |
| 60 |
|
\caption{ \label{fig:mtrhocomp}%\protect |
| 69 |
|
\end{center} |
| 70 |
|
\end{figure} |
| 71 |
|
|
| 72 |
< |
\begin{figure}[hb] |
| 72 |
> |
\begin{figure}[!hb] |
| 73 |
|
\begin{center} |
| 74 |
|
\includegraphics[width=0.5\linewidth]{plots/metphi.pdf}% |
| 75 |
|
\includegraphics[width=0.5\linewidth]{plots/metphi_phicorr.pdf} |
| 80 |
|
\end{center} |
| 81 |
|
\end{figure} |
| 82 |
|
|
| 83 |
+ |
\clearpage |
| 84 |
+ |
|
| 85 |
|
\subsection{Branching Fraction Correction} |
| 86 |
|
|
| 87 |
|
The leptonic branching fraction used in some of the \ttbar\ MC samples |
| 88 |
< |
differs from the value listed in the PDG $(10.80 ± 0.09)\%$. |
| 88 |
> |
differs from the value listed in the PDG $(10.80 \pm 0.09)\%$. |
| 89 |
|
Table.~\ref{tab:wlepbf} summarizes the branching fractions used in |
| 90 |
|
the generation of the various \ttbar\ MC samples. |
| 91 |
|
For \ttbar\ samples with the incorrect leptonic branching fraction, event |
