| 1 |
|
\section{Event Preselection} |
| 2 |
|
\label{sec:eventSel} |
| 3 |
< |
%{\color{red} This needs to be fixed up -- probably many mistakes present.}\\ |
| 4 |
< |
As mentioned in the introduction, the preselection is based on the |
| 5 |
< |
$t\bar{t}$ analysis. We select events with two opposite sign isolated |
| 3 |
> |
The purpose of the preselection is to define a data sample rich |
| 4 |
> |
in $t\bar{t} \to$ dileptons. We compare the kinematical |
| 5 |
> |
properties of this sample with expectations from $t\bar{t}$ |
| 6 |
> |
Monte Carlo. |
| 7 |
> |
|
| 8 |
> |
The preselection is based on the |
| 9 |
> |
$t\bar{t}$ analysis~\cite{ref:top}. |
| 10 |
> |
We select events with two opposite sign isolated |
| 11 |
|
leptons ($ee$, $e\mu$, or $\mu\mu$); one of the leptons must |
| 12 |
|
have $P_T > 20$ GeV, |
| 13 |
|
the other one must have $P_T > 10$ GeV. Events consistent with $Z$ are rejected. |
| 80 |
|
|
| 81 |
|
\begin{itemize} |
| 82 |
|
|
| 83 |
< |
\item $P_T > 10$ GeV. (The $t\bar{t}$ analysis uses 20 GeV but for |
| 84 |
< |
completeness we calculate FR down to 10 GeV). |
| 83 |
> |
% \item $P_T > 10$ GeV. (The $t\bar{t}$ analysis uses 20 GeV but for |
| 84 |
> |
% completeness we calculate FR down to 10 GeV). |
| 85 |
|
|
| 86 |
|
\item $|\eta| < 2.5$. |
| 87 |
|
|
| 136 |
|
\label{sec:trigSel} |
| 137 |
|
|
| 138 |
|
Because most of the triggers implemented in the 2nd half of the |
| 139 |
< |
2010 run were not implemented in the Monte Carlo, no trigger |
| 140 |
< |
selection is applied on Monte Carlo data. As discussed in |
| 139 |
> |
2010 run were not implemented in the Monte Carlo, |
| 140 |
> |
we do not make any requirements on HLT bits in the Monte Carlo. |
| 141 |
> |
Instead, as discussed in |
| 142 |
|
Section~\ref{sec:trgEff}, a trigger efficiency weight is applied |
| 143 |
|
to each event, based on the trigger efficiencies measured on data. |
| 144 |
|
Trigger efficiency weights are very close to 1. |
