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vuko |
1.1 |
\section{Event reconstruction}
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\label{sec:eventReconstruction}
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vuko |
1.2 |
The four possible final states of \WZ
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vuko |
1.5 |
production with electrons and muons in the final state are studied, $\rm e^\pm \epem$, $\mu^\pm \epem$, $\rm e^\pm \mu^+\mu^-$
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vuko |
1.2 |
and $\mu^\pm \mu^+\mu^-$. They are associated to four possible classes,
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denoted as follows:
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\begin{itemize}
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\item $3e$: for \WZ events with $\W \to e \nu$ and $\Z\to \epem$.
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\item $2e1\mu$: for \WZ events with $\W \to \mu \nu$ and $\Z\to \epem$.
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\item $2\mu 1e$: for \WZ events with $\W \to e \nu$ and $\Z\to \mumu$.
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\item $3\mu$: for \WZ events with $\W \to \mu \nu$ and $\Z\to \mumu$.
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\end{itemize}
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vuko |
1.1 |
\subsection{Trigger selection and efficiencies}
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vuko |
1.2 |
Events stemming from the three-lepton final states of $\WZ$ production
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beaucero |
1.4 |
are collected by the electron and/or muon triggers. For each channel,
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vuko |
1.2 |
a minimun number of HLT requirements is chosen while keeping
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the HLT efficiency for selected events close to 100\%. The same
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HLT requirements are used for channels with the same Z decay mode:
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\begin{itemize}
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\item for $3e$ and $2e1\mu$: HLTSingleElectron or HLTDoubleElectronRelaxed
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\item for $2\mu1e$ and $3\mu$: HLTSingleMuonIso
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\end{itemize}
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The HLT efficiencies for all modes for events passing the full
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selection described in this section are given in table~\ref{tab:hlteff}.
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\begin{table}[tbph]
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\begin{center}
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\begin{tabular}{llc} \hline \hline
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Channel & HLT selection & HLT efficiency \\ \hline
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$3e$ & HLTSingleElectron or HLTDoubleElectronRelaxed & 0.996 \\
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$2e1\mu$ & HLTSingleElectron or HLTDoubleElectronRelaxed & 0.969 \\
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$2\mu 1e$ & HLTSingleMuonIso & 0.966 \\
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$3\mu$ & HLTSingleMuonIso & 0.994 \\ \hline \hline
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\end{tabular}
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\end{center}
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\caption{HLT Efficiencies, in percent, for all
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vuko |
1.11 |
the events in the generated phase space that have been retained by
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vuko |
1.2 |
the complete event selection.}
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\label{tab:hlteff}
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\end{table}
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vuko |
1.1 |
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vuko |
1.10 |
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\begin{figure}[tbp]
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\begin{center}
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\scalebox{0.7}{\includegraphics{figs/mu_isol.eps}}
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\caption{Muon isolation variables for the muon associated
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to the \W-boson decay in $2e1\mu$ events: the left plot
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shows the sum of calorimetric energy in a $\Delta R=0.3$ cone
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around the muon candidate; the right plot shows the sum of
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transverse momenta of tracks within a $\Delta R = 0.25$ cone around
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the muon candidate. The normalization of signal and background
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distributions is arbitrary.
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}
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\label{fig:mu_isol}
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\end{center}
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\end{figure}
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\begin{figure}[tb]
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\begin{center}
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\scalebox{0.6}{\includegraphics{figs/mu_SIP.eps}}
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\caption{
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Muon impact parameter significance distribution
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in $2e1\mu$ events. The normalization of signal and background
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distributions is arbitrary.
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}
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\label{fig:mu_SIP}
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\end{center}
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\end{figure}
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vuko |
1.1 |
\subsection{Lepton identification}
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vuko |
1.2 |
\label{sec:leptonId}
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vuko |
1.1 |
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vuko |
1.2 |
The requirements used for electron identification in this analysis are described
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in~\cite{noteElectronID}.
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Muon candidates are selected from global muons, which are reconstructed
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combining measurements in the muon chambers and the central tracker.
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An additional isolation criterion requires that the energy
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measured in the calorimeters within a $\Delta R = 0.3$ cone around the
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muon must be smaller than 3 GeV and the sum of the $p_t$ of tracks
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vuko |
1.7 |
within a $\Delta R = 0.25$ cone around the muon must be smaller than 2 \gev.
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These cuts reduce the background from muons originated in
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vuko |
1.2 |
\b-quark decays of the $\Zbbbar$ background, which are close to tracks
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and clusters from the other \b-quark decay products.
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%Figures~\ref{fig:muonisol} and ~\ref{fig:muonisoleffi} show the
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%performance of the isolation cut. The distribution of the isolation
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%variables for the $\Z\b\bbar(\epem\b\bbar)$ is particularly
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%interesting, since muons only stem from \b-quark decays.
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vuko |
1.1 |
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vuko |
1.3 |
The significance of the muon impact parameter in the plane
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transverse to the beam, $S_{IP}$, discriminates against leptons from
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heavy-quark decays in all Standard Model background processes. This
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variable is defined as the ratio between the measured impact parameter
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and its uncertainty: $S_{IP}=IP/\sigma_{IP}$, and is required to
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satisfy $S_{IP}<3$. This requirement is applied only for muons
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vuko |
1.9 |
and not for electrons. For electrons, a significant fraction of the
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background comes from fake electrons and not from heavy quark decays,
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and a cut on the impact parameter significance shows no improvement
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vuko |
1.11 |
in significance for the $\W\to e$ channels, as can be seen in
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Figure~\ref{fig:wl_IP_SvsCut}.
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vuko |
1.3 |
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vuko |
1.10 |
\begin{figure}[p]
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\begin{center}
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\scalebox{0.6}{\includegraphics{figs/wl_IP_eff.eps}}
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\caption{Efficiency for signal and background as a function
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of the cut value on the \W-boson lepton impact parameter
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significance. All other cuts but the cut on this variable
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are applied.
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% Only events with 81.1 GeV $< M_Z < $ 101.1 \gev
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% are considered.
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}
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\label{fig:wl_IP_eff}
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\end{center}
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%\end{figure}
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%\begin{figure}[bt]
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\begin{center}
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\scalebox{0.6}{\includegraphics{figs/wl_IP_SvsCut.eps}}
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\caption{Signal significance as a function of the cut value on
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the \W-boson lepton impact parameter significance. All other cuts but
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the cut on this variable are applied.
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% Only events with 81.1 GeV $< M_Z < $ 101.1 \gev are considered.
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}
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\label{fig:wl_IP_SvsCut}
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\end{center}
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\end{figure}
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vuko |
1.3 |
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vuko |
1.1 |
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vuko |
1.7 |
\begin{table}[tbp]
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\begin{tabular}{|l|c|c|c|c|} \hline
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& $3e$ & $2e1\mu$ & $2\mu 1e$ & $3\mu$ \\ \hline \hline
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\multicolumn{5}{|c|}{Lepton selection} \\ \hline
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Electrons & \multicolumn{3}{|c|}{{\tt SimpleLoose} requirements for Z reconstruction} & \\
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& \multicolumn{3}{|c|}{{\tt SimpleTight} requirements for W} & \\ \hline
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Muons & & \multicolumn{3}{|c|}{ Track Isolation:$ {\tt IsoTrack}(\Delta R= 0.25) < 2 \gev$} \\
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& & \multicolumn{3}{|c|}{ Calorimetric Isolation:$ {\tt IsoCalo}(\Delta R = 0.3) < 5 \gev$} \\
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& & \multicolumn{3}{|c|}{$S_{IP}=IP/\sigma_{IP}<3$ } \\ \hline
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HLT requirement & \multicolumn{2}{|c|}{ HLTSingleElectron or HLTDoubleElectronRelaxed}
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& \multicolumn{2}{|c|}{ HLTSingleMuonIso} \\ \hline
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\multicolumn{5}{|c|}{Z reconstruction} \\ \hline
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Lepton cuts & \multicolumn{4}{|c|}{for both Z leptons: $p_t > 15 GeV$} \\
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Mass window & \multicolumn{4}{|c|}{$50 \gev < M_Z < 120 \gev $ } \\
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Second Z veto & \multicolumn{4}{|c|}{No independent second Z candidate with $50 \gev < M_Z < 120 \gev $ } \\ \hline
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\multicolumn{5}{|c|}{W lepton selection} \\ \hline
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Other cuts & & & $\Delta R(\mu_Z,e_W)>0.1$ & \\ \hline
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Signal region & \multicolumn{4}{|c|}{$81 \gev < M_Z < 101 \gev $ } \\ \hline \hline
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\end{tabular}
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\caption{Summary of all cuts used in the WZ selection}
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\label{tab:allcuts}
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\end{table}
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\begin{figure}[p]
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\begin{center}
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\scalebox{0.6}{\includegraphics{figs/wlpt_cuteff.eps}}
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\caption{Efficiency for signal and background as a function
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of the cut value on the \W-boson lepton transverse momentum.
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All other cuts but the cut on this variable are applied.
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Only events with 81.1 GeV $< M_Z < $ 101.1 \gev
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are considered.}
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\label{fig:wlpt_cuteff}
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\end{center}
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%\end{figure}
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%\begin{figure}[bt]
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\begin{center}
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\scalebox{0.6}{\includegraphics{figs/wlpt_cutS.eps}}
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\caption{Signal significance as a function of the cut value on
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the \W-boson lepton transverse momentum. All other cuts but
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the cut on this variable are applied. Only events with
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81.1 GeV $< M_Z < $ 101.1 \gev are considered.}
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\label{fig:wlpt_cutS}
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\end{center}
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\end{figure}
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vuko |
1.1 |
\subsection{\WZ candidate selection}
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vuko |
1.2 |
Events are accepted if they contain at least three charged leptons,
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vuko |
1.3 |
either electrons or muons, with $p_t > 15\,\mathrm{GeV}$ and $| \eta | < 2.5$ for
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electrons,$| \eta | < 2.4$ for muons.
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as discussed in~\ref{sec:leptonId}.
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vuko |
1.2 |
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The \WZ candidate selection proceeds from building all possible
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\Z-boson candidates from same-flavour opposite-charge lepton pairs.
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For $\Z \to ee$ decays, electrons have to fullfil the loose requirements
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defined in~\cite{noteElectronID}.
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Events are retained if the mass of this \Z-boson candidate is
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within 20 GeV of the Z-boson mass,$m_Z$. The event is
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rejected if a second Z candidate is found. This second Z candidate is done
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with all possible same-flavour opposite-charge combinations which are left
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after removing the two leptons already used for the first Z candidate. This
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vuko |
1.11 |
veto on the presence of a second Z helps to suppress $ZZ$ events.
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%The invariant
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%mass distribution for accepted \Z candidates is shown in
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%Figure~\ref{fig:zcandidates}.
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vuko |
1.2 |
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% and the \Z mass resolution is shown in
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%Figure~\ref{fig:dzmass}.
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After the \Z-boson candidate is identified, the lepton associated
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to the \W-boson decay is chosen from the remaining electrons and muons
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in the event that have not been used for reconstructing the \Z-boson.
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Electrons are required to pass the tight criteria described in
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\cite{noteElectronID}. If the event contains more than three leptons,
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the highest $p_t$ is chosen as the one from the \W-boson decay, and
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the additional leptons are not considered further.
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The transverse momentum of this lepton is required to be larger
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than 20 GeV. This last requirement is effective in rejecting
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vuko |
1.7 |
the \Zbbbar and \Zjets backgrounds, see Figure~\ref{fig:wlpt_cuteff},
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and the cut value is chosen in
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vuko |
1.2 |
the range that maximises the significance as shown in
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vuko |
1.7 |
Figure~\ref{fig:wlpt_cutS}.
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vuko |
1.2 |
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vuko |
1.6 |
An additional requirement on the isolation between electron and muons is applied
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for the $2\mu 1e$ channel, by demanding $\Delta R$ between the electron associated
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to the \W-decay and any of the two muons associated to the \Z-decay be greater than
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0.1. This requirement allows to suppress the contributions of $\Z \to \mu\mu$
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decays, where one of the two muons radiates a photon which is reconstructed
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as electrons, possibly after conversion, which shows up as a peak at around 60 GeV
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in the Z mass distribution, as shown in figure~\ref{fig:Z2mu1e_60GeVPeak}.
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vuko |
1.11 |
The summary of the selection is given in Table~\ref{tab:allcuts}.
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vuko |
1.7 |
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vuko |
1.2 |
The expected number of events passing the various steps of the selection
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vuko |
1.11 |
is listed in Tables~\ref{tab:sel-effA}.
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vuko |
1.2 |
Table~\ref{tab:wz-effimatrix} lists the final selection efficiency for
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| 240 |
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the different generated \W and \Z decays. It can be seen there that \WZ\
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events with both the \W and the \Z boson decaying into electrons or muons
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almost always get reconstructed with the correct flavour. It is to be
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noted in addition that each of our four selection channels gets a small
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contribution from $W \to \tau \to e/\mu$ decays as one would expect. The
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selection efficiency for these events is however smaller which is mostly due
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to the \pt cut on the third lepton, since the \pt spectrum of electrons or
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muons from $W \to \tau \to e/\mu$ decays is softer.
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vuko |
1.11 |
Tables~ref\label{tab:wz-matcheffi-Zee} and \label{tab:wz-matcheffi-Zmumu} show
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the fraction of reconstructed \WZ events with with correclty matched leptons
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It is in particular worth mentioning that the lepton associated to the \W-decay
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is correclty matched to the true lepton from the \W-decay in more than 90\% of
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the cases even for events with several lepton candidates available to be associated
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to the \W-decay. The choice to take the candidate with the leading \pt is therefore
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justified.
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vuko |
1.3 |
\begin{table}[p]
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\begin{center}
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| 259 |
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| 260 |
vuko |
1.9 |
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| 262 |
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| 263 |
vuko |
1.3 |
\begin{tabular}{lcccc} \hline
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vuko |
1.9 |
\multicolumn{5}{c}{ {\bf $3e$ Channel}} \\ \hline \hline
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Step & WZ & bbll & Z+jets & TTbar+jets\\ \hline
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All events & 546 & 72770.4 & 1.2679e+06 & 17556.1 \\
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Found $Z \to ee$ & 204.969 (37.5401 \%) & 27800.5 (38.203 \%) & 502344 (39.62 \%) & 2920.59 (16.6357 \%) \\
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Found $W \to e$ & 41.9925 (20.4872 \%) & 171.053 (0.615286 \%) & 309.563 (0.0616238 \%) & 13.8293 (0.473511 \%) \\
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W Lepton Pt cut & 34.8561 (83.0056 \%) & 23.7161 (13.8648 \%) & 86.7924 (28.037 \%) & 8.25515 (59.6931 \%) \\
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Passes HLT & 34.7185 (99.6052 \%) & 23.5679 (99.375 \%) & 86.7924 (100 \%) & 8.25515 (100 \%) \\
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Z mass window & 31.5533 (90.8834 \%) & 17.4906 (74.2138 \%) & 51.8927 (59.7894 \%) & 3.2585 (39.4724 \%) \\ \hline
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Overall efficiency & 5.77899 \% & 0.0240354 \% & 0.00409279 \% & 0.0185605 \% \\
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vuko |
1.3 |
\hline
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\end{tabular}
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| 275 |
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\begin{tabular}{lcccc} \hline
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| 276 |
vuko |
1.9 |
\multicolumn{5}{c}{ {\bf $2e1\mu$ Channel}} \\ \hline \hline
|
| 277 |
|
|
Step & WZ & bbll & Z+jets & \ttjets\\ \hline
|
| 278 |
|
|
All events & 546 & 72770.4 & 1.2679e+06 & 17556.1 \\
|
| 279 |
|
|
Found $Z \to ee$ & 204.969 (37.5401 \%) & 27800.5 (38.203 \%) & 502344 (39.62 \%) & 2920.59 (16.6357 \%) \\
|
| 280 |
|
|
Found $W \to \mu$ & 47.9099 (23.3743 \%) & 747.725 (2.68961 \%) & 2194.09 (0.436771 \%) & 56.7645 (1.9436 \%) \\
|
| 281 |
|
|
W Lepton Pt cut & 37.0973 (77.4313 \%) & 9.63467 (1.28853 \%) & 9.57604 (0.436446 \%) & 17.5382 (30.8965 \%) \\
|
| 282 |
|
|
Passes HLT & 36.1929 (97.5623 \%) & 9.26411 (96.1538 \%) & 8.32189 (86.9033 \%) & 15.2488 (86.9457 \%) \\
|
| 283 |
|
|
Z mass window & 32.5166 (89.8425 \%) & 8.15242 (88 \%) & 7.31467 (87.8968 \%) & 4.91533 (32.2343 \%) \\ \hline
|
| 284 |
|
|
Overall efficiency & 5.95542 \% & 0.0112029 \% & 0.000576911 \% & 0.0279978 \% \\
|
| 285 |
vuko |
1.3 |
\hline
|
| 286 |
|
|
\end{tabular}
|
| 287 |
|
|
|
| 288 |
|
|
\begin{tabular}{lcccc} \hline
|
| 289 |
vuko |
1.9 |
\multicolumn{5}{c}{ {\bf $2\mu1e$ Channel}} \\ \hline \hline
|
| 290 |
|
|
Step & WZ & bbll & Z+jets & TTbar+jets\\ \hline
|
| 291 |
|
|
All events & 546 & 72770.4 & 1.2679e+06 & 17556.1 \\
|
| 292 |
|
|
Found $Z \to \mu\mu$ & 233.75 (42.8114 \%) & 31889.4 (43.8219 \%) & 577257 (45.5284 \%) & 2778.81 (15.8282 \%) \\
|
| 293 |
|
|
Found $W \to e$ & 48.7553 (20.8579 \%) & 213.519 (0.669562 \%) & 701.695 (0.121557 \%) & 15.1085 (0.543704 \%) \\
|
| 294 |
|
|
W Lepton Pt cut & 40.6556 (83.3871 \%) & 50.6191 (23.707 \%) & 464.493 (66.196 \%) & 10.2745 (68.0047 \%) \\
|
| 295 |
|
|
$\Delta R(e,\mu)$ cut & 40.5573 (99.7582 \%) & 23.3456 (46.1201 \%) & 92.9813 (20.0178 \%) & 7.14967 (69.5865 \%) \\
|
| 296 |
|
|
Passes HLT & 39.4171 (97.1886 \%) & 23.1973 (99.3651 \%) & 88.7791 (95.4806 \%) & 6.6245 (92.6546 \%) \\
|
| 297 |
|
|
Z mass window & 35.5638 (90.2244 \%) & 18.8988 (81.4696 \%) & 50.2509 (56.6022 \%) & 2.84083 (42.8837 \%) \\ \hline
|
| 298 |
|
|
Overall efficiency & 6.51352 \% & 0.0259704 \% & 0.00396331 \% & 0.0161814 \% \\
|
| 299 |
vuko |
1.3 |
\hline
|
| 300 |
|
|
\end{tabular}
|
| 301 |
|
|
|
| 302 |
vuko |
1.9 |
|
| 303 |
vuko |
1.3 |
\begin{tabular}{lcccc} \hline
|
| 304 |
vuko |
1.9 |
\multicolumn{5}{c}{ {\bf $3\mu$ Channel}} \\ \hline \hline
|
| 305 |
|
|
Step & WZ & bbll & Z+jets & TTbar+jets\\ \hline
|
| 306 |
|
|
All events & 546 & 72770.4 & 1.2679e+06 & 17556.1 \\
|
| 307 |
|
|
Found $Z \to \mu\mu$ & 233.75 (42.8114 \%) & 31889.4 (43.8219 \%) & 577257 (45.5284 \%) & 2778.81 (15.8282 \%) \\
|
| 308 |
|
|
Found $W \to \mu$ & 57.7986 (24.7267 \%) & 810.721 (2.54229 \%) & 2520.69 (0.436668 \%) & 35.3061 (1.27054 \%) \\
|
| 309 |
|
|
W Lepton Pt cut & 44.2533 (76.5646 \%) & 8.89355 (1.09699 \%) & 1.84115 (0.0730414 \%) & 1.683 (4.76688 \%) \\
|
| 310 |
|
|
Passes HLT & 43.9977 (99.4225 \%) & 8.89355 (100 \%) & 1.84115 (100 \%) & 1.683 (100 \%) \\
|
| 311 |
|
|
Z mass window & 40.0462 (91.0188 \%) & 7.78185 (87.5 \%) & 1.84115 (100 \%) & 1.15783 (68.7957 \%) \\ \hline
|
| 312 |
|
|
Overall efficiency & 7.33446 \% & 0.0106937 \% & 0.000145212 \% & 0.00659501 \% \\
|
| 313 |
vuko |
1.3 |
\hline
|
| 314 |
|
|
\end{tabular}
|
| 315 |
vuko |
1.9 |
|
| 316 |
|
|
|
| 317 |
vuko |
1.3 |
\caption{Expected number of signal and background events passing the different
|
| 318 |
vuko |
1.9 |
selections steps in the \WZ, \Zbbbar, \Zjets and \ttjets samples for an integrated luminosity
|
| 319 |
vuko |
1.3 |
of 1 \invfb.}
|
| 320 |
|
|
\label{tab:sel-effA}
|
| 321 |
|
|
\end{center}
|
| 322 |
|
|
\end{table}
|
| 323 |
|
|
|
| 324 |
vuko |
1.11 |
\begin{table}[p]
|
| 325 |
vuko |
1.7 |
\begin{center}
|
| 326 |
|
|
\begin{tabular}{lccccc}
|
| 327 |
|
|
\hline \hline
|
| 328 |
|
|
& \multicolumn{5}{c}{$Z \to ee $} \\
|
| 329 |
|
|
& $W \to e$
|
| 330 |
|
|
& $W \to \mu$
|
| 331 |
|
|
& $W \to \tau \to e$
|
| 332 |
|
|
& $W \to \tau \to \mu$
|
| 333 |
|
|
& $W \to \tau \to hadrons$
|
| 334 |
|
|
\\ \hline
|
| 335 |
|
|
$3e$ & 17.4 \% & 0.0319 \% & 6.42 \% & 0 \% & 0.162 \% \\
|
| 336 |
|
|
$2e1\mu$ & 0 \% & 18.6 \% & 0 \% & 5.53 \% & 0.0485 \% \\
|
| 337 |
|
|
$2\mu1e$ & 0 \% & 0 \% & 0 \% & 0 \% & 0 \% \\
|
| 338 |
|
|
$3\mu$ & 0 \% & 0 \% & 0 \% & 0 \% & 0 \% \\
|
| 339 |
|
|
\hline \hline
|
| 340 |
|
|
& \multicolumn{5}{c}{$Z \to \mu\mu $} \\
|
| 341 |
|
|
& $W \to e$
|
| 342 |
|
|
& $W \to \mu$
|
| 343 |
|
|
& $W \to \tau \to e$
|
| 344 |
|
|
& $W \to \tau \to \mu$
|
| 345 |
|
|
& $W \to \tau \to hadrons$
|
| 346 |
|
|
\\ \hline
|
| 347 |
|
|
$3e$ & 0 \% & 0 \% & 0 \% & 0 \% & 0 \% \\
|
| 348 |
|
|
$2e1\mu$ & 0.0104 \% & 0 \% & 0 \% & 0 \% & 0 \% \\
|
| 349 |
|
|
$2\mu1e$ & 19.6 \% & 0.0208 \% & 5.56 \% & 0 \% & 0.18 \% \\
|
| 350 |
|
|
$3\mu$ & 0 \% & 23.4 \% & 0.0573 \% & 6.77 \% & 0.0164 \% \\
|
| 351 |
|
|
\hline \hline
|
| 352 |
|
|
\end{tabular}
|
| 353 |
|
|
\end{center}
|
| 354 |
|
|
\caption{Selection efficiency for signal events in the four selection channels for the different
|
| 355 |
|
|
generated \W and \Z decay channels.}
|
| 356 |
|
|
\label{tab:wz-effimatrix}
|
| 357 |
|
|
|
| 358 |
vuko |
1.11 |
%\end{table}
|
| 359 |
|
|
%\begin{table}[tbp]
|
| 360 |
vuko |
1.7 |
\begin{center}
|
| 361 |
|
|
\begin{tabular}{llcc} \hline
|
| 362 |
|
|
& & \multicolumn{2}{c}{Generated decay:} \\
|
| 363 |
|
|
& & \multicolumn{2}{c}{$Z \to ee $} \\
|
| 364 |
|
|
Selection channel & & $W \to e$ & $W \to \mu$ \\ \hline
|
| 365 |
|
|
\hline \hline
|
| 366 |
|
|
\multicolumn{4}{c}{all} \\ \hline
|
| 367 |
|
|
$3e$ & all & 1644 & 3 \\
|
| 368 |
|
|
$3e$ & matched Z & 0.937+/-0.00598 & 1+/-0\\
|
| 369 |
|
|
$3e$ & matched W & 0.915+/-0.00688 & 0+/--1\\
|
| 370 |
|
|
$3e$ & matched WZ & 0.914+/-0.00691 & 0+/--1\\
|
| 371 |
|
|
\hline \hline
|
| 372 |
|
|
\multicolumn{4}{c}{exactly 1 W lepton candidate} \\ \hline
|
| 373 |
|
|
$3e$ & all & 1602 & 0 \\
|
| 374 |
|
|
$3e$ & matched Z & 0.938+/-0.00604 & -1+/--1\\
|
| 375 |
|
|
$3e$ & matched W & 0.915+/-0.00696 & -1+/--1\\
|
| 376 |
|
|
$3e$ & matched WZ & 0.914+/-0.00699 & -1+/--1\\
|
| 377 |
|
|
\hline \hline
|
| 378 |
|
|
\multicolumn{4}{c}{more than 1 W lepton candidate} \\ \hline
|
| 379 |
|
|
$3e$ & all & 42 & 3 \\
|
| 380 |
|
|
$3e$ & matched Z & 0.929+/-0.0397 & 1+/-0\\
|
| 381 |
|
|
$3e$ & matched W & 0.905+/-0.0453 & 0+/--1\\
|
| 382 |
|
|
$3e$ & matched WZ & 0.905+/-0.0453 & 0+/--1\\
|
| 383 |
|
|
\hline \hline
|
| 384 |
|
|
\multicolumn{4}{c}{all} \\ \hline
|
| 385 |
|
|
$2e1\mu$ & all & 0 & 1746 \\
|
| 386 |
|
|
$2e1\mu$ & matched Z & -1+/--1 & 0.999+/-0.000573\\
|
| 387 |
|
|
$2e1\mu$ & matched W & -1+/--1 & 1+/-0\\
|
| 388 |
|
|
$2e1\mu$ & matched WZ & -1+/--1 & 0.999+/-0.000573\\
|
| 389 |
|
|
\hline \hline
|
| 390 |
|
|
\multicolumn{4}{c}{exactly 1 W lepton candidate} \\ \hline
|
| 391 |
|
|
$2e1\mu$ & all & 0 & 1715 \\
|
| 392 |
|
|
$2e1\mu$ & matched Z & -1+/--1 & 0.999+/-0.000583\\
|
| 393 |
|
|
$2e1\mu$ & matched W & -1+/--1 & 1+/-0\\
|
| 394 |
|
|
$2e1\mu$ & matched WZ & -1+/--1 & 0.999+/-0.000583\\
|
| 395 |
|
|
\hline \hline
|
| 396 |
|
|
\multicolumn{4}{c}{more than 1 W lepton candidate} \\ \hline
|
| 397 |
|
|
$2e1\mu$ & all & 0 & 31 \\
|
| 398 |
|
|
$2e1\mu$ & matched Z & -1+/--1 & 1+/-0\\
|
| 399 |
|
|
$2e1\mu$ & matched W & -1+/--1 & 1+/-0\\
|
| 400 |
|
|
$2e1\mu$ & matched WZ & -1+/--1 & 1+/-0\\ \hline \hline
|
| 401 |
|
|
\end{tabular}
|
| 402 |
|
|
\end{center}
|
| 403 |
|
|
\caption{Fractions of events with correctly matched leptons
|
| 404 |
|
|
to true decay product of \W and \Z decays for final states
|
| 405 |
|
|
with generated $\Z\to ee$ decays}
|
| 406 |
|
|
\label{tab:wz-matcheffi-Zee}
|
| 407 |
|
|
\end{table}
|
| 408 |
|
|
|
| 409 |
|
|
|
| 410 |
|
|
|
| 411 |
|
|
\begin{table}[tbp]
|
| 412 |
|
|
\begin{center}
|
| 413 |
|
|
\begin{tabular}{llcc} \hline
|
| 414 |
|
|
& & \multicolumn{2}{c}{Generated decay:} \\
|
| 415 |
|
|
& & \multicolumn{2}{c}{$Z \to \mu\mu $} \\
|
| 416 |
|
|
Selection channel & & $W \to e$ & $W \to \mu$
|
| 417 |
|
|
\\ \hline
|
| 418 |
|
|
\hline \hline
|
| 419 |
|
|
\multicolumn{4}{c}{all} \\ \hline
|
| 420 |
|
|
$2\mu1e$ & all & 1895 & 2 \\
|
| 421 |
|
|
$2\mu1e$ & matched Z & 1+/-0 & 1+/-0\\
|
| 422 |
|
|
$2\mu1e$ & matched W & 0.985+/-0.00282 & 0+/--1\\
|
| 423 |
|
|
$2\mu1e$ & matched WZ & 0.985+/-0.00282 & 0+/--1\\
|
| 424 |
|
|
\hline \hline
|
| 425 |
|
|
\multicolumn{4}{c}{exactly 1 W lepton candidate} \\ \hline
|
| 426 |
|
|
$2\mu1e$ & all & 1847 & 0 \\
|
| 427 |
|
|
$2\mu1e$ & matched Z & 1+/-0 & -1+/--1\\
|
| 428 |
|
|
$2\mu1e$ & matched W & 0.986+/-0.00274 & -1+/--1\\
|
| 429 |
|
|
$2\mu1e$ & matched WZ & 0.986+/-0.00274 & -1+/--1\\
|
| 430 |
|
|
\hline \hline
|
| 431 |
|
|
\multicolumn{4}{c}{more than 1 W lepton candidate} \\ \hline
|
| 432 |
|
|
$2\mu1e$ & all & 48 & 2 \\
|
| 433 |
|
|
$2\mu1e$ & matched Z & 1+/-0 & 1+/-0\\
|
| 434 |
|
|
$2\mu1e$ & matched W & 0.938+/-0.0349 & 0+/--1\\
|
| 435 |
|
|
$2\mu1e$ & matched WZ & 0.938+/-0.0349 & 0+/--1\\
|
| 436 |
|
|
\hline \hline
|
| 437 |
|
|
\multicolumn{4}{c}{all} \\ \hline
|
| 438 |
|
|
$3\mu$ & all & 0 & 2251 \\
|
| 439 |
|
|
$3\mu$ & matched Z & -1+/--1 & 0.943+/-0.00488\\
|
| 440 |
|
|
$3\mu$ & matched W & -1+/--1 & 0.933+/-0.00526\\
|
| 441 |
|
|
$3\mu$ & matched WZ & -1+/--1 & 0.933+/-0.00526\\
|
| 442 |
|
|
\hline \hline
|
| 443 |
|
|
\multicolumn{4}{c}{exactly 1 W lepton candidate} \\ \hline
|
| 444 |
|
|
$3\mu$ & all & 0 & 2207 \\
|
| 445 |
|
|
$3\mu$ & matched Z & -1+/--1 & 0.944+/-0.0049\\
|
| 446 |
|
|
$3\mu$ & matched W & -1+/--1 & 0.934+/-0.00529\\
|
| 447 |
|
|
$3\mu$ & matched WZ & -1+/--1 & 0.934+/-0.00529\\
|
| 448 |
|
|
\hline \hline
|
| 449 |
|
|
\multicolumn{4}{c}{more than 1 W lepton candidate} \\ \hline
|
| 450 |
|
|
$3\mu$ & all & 0 & 44 \\
|
| 451 |
|
|
$3\mu$ & matched Z & -1+/--1 & 0.909+/-0.0433\\
|
| 452 |
|
|
$3\mu$ & matched W & -1+/--1 & 0.909+/-0.0433\\
|
| 453 |
|
|
$3\mu$ & matched WZ & -1+/--1 & 0.909+/-0.0433\\ \hline \hline
|
| 454 |
|
|
\end{tabular}
|
| 455 |
|
|
\end{center}
|
| 456 |
|
|
\caption{Fractions of MC \WZ events with correctly matched leptons
|
| 457 |
|
|
to true decay product of \W and \Z decays for final states
|
| 458 |
|
|
with generated $\Z\to \mu\mu$ decays}
|
| 459 |
|
|
\label{tab:wz-matcheffi-Zmumu}
|
| 460 |
|
|
\end{table}
|
| 461 |
|
|
|
| 462 |
vuko |
1.11 |
|
| 463 |
|
|
%\subsection{Signal extraction}
|
| 464 |
|
|
%\input D0Matrix
|
| 465 |
|
|
\input zjetbackground
|
| 466 |
|
|
|
| 467 |
|
|
|
| 468 |
|
|
\section{Systematic uncertainties}
|
| 469 |
|
|
\input Sys
|
| 470 |
|
|
|
| 471 |
|
|
|
| 472 |
|
|
\begin{figure}[bt]
|
| 473 |
|
|
\begin{center}
|
| 474 |
|
|
\scalebox{0.8}{\includegraphics{figs/met_by_channel.eps}}
|
| 475 |
|
|
\caption{Missing transverse mass for the four signal categories.
|
| 476 |
|
|
The distributions show the number of expected events
|
| 477 |
|
|
for $1 fb^{-1}$. Only events with 81.1 GeV $< M_Z < $ 101.1 \gev
|
| 478 |
|
|
are shown. All selection cuts are applied.}
|
| 479 |
|
|
\label{fig:met}
|
| 480 |
|
|
\end{center}
|
| 481 |
|
|
\end{figure}
|
| 482 |
|
|
|
| 483 |
|
|
\begin{figure}[bt]
|
| 484 |
|
|
\begin{center}
|
| 485 |
|
|
\scalebox{0.8}{\includegraphics{figs/mtw_by_channel.eps}}
|
| 486 |
|
|
\caption{W transverse mass for the four signal categories.
|
| 487 |
|
|
The distributions show the number of expected events
|
| 488 |
|
|
for $1 fb^{-1}$. Only events with 81.1 GeV $< M_Z < $ 101.1 GeV are shown.
|
| 489 |
|
|
All selection cuts are applied.}
|
| 490 |
|
|
\label{fig:mtw}
|
| 491 |
|
|
\end{center}
|
| 492 |
|
|
\end{figure}
|
| 493 |
|
|
|
| 494 |
|
|
|
| 495 |
|
|
|
| 496 |
|
|
|
| 497 |
|
|
|
