| 2 |
|
\label{sec:eventReconstruction} |
| 3 |
|
|
| 4 |
|
The four possible final states of \WZ |
| 5 |
< |
production with electrons and muons are studied, $\rm e^\pm \epem$, $\mu^\pm \epem$, $\rm e^\pm \mu^+\mu^-$ |
| 5 |
> |
production with electrons and muons in the final state are studied, $\rm e^\pm \epem$, $\mu^\pm \epem$, $\rm e^\pm \mu^+\mu^-$ |
| 6 |
|
and $\mu^\pm \mu^+\mu^-$. They are associated to four possible classes, |
| 7 |
|
denoted as follows: |
| 8 |
|
\begin{itemize} |
| 16 |
|
\subsection{Trigger selection and efficiencies} |
| 17 |
|
|
| 18 |
|
Events stemming from the three-lepton final states of $\WZ$ production |
| 19 |
< |
are collected by the electron and muon triggers. For each channel, |
| 19 |
> |
are collected by the electron and/or muon triggers. For each channel, |
| 20 |
|
a minimun number of HLT requirements is chosen while keeping |
| 21 |
|
the HLT efficiency for selected events close to 100\%. The same |
| 22 |
|
HLT requirements are used for channels with the same Z decay mode: |
| 41 |
|
|
| 42 |
|
\end{center} |
| 43 |
|
\caption{HLT Efficiencies, in percent, for all |
| 44 |
< |
the events in the generated phase space for events retained by |
| 44 |
> |
the events in the generated phase space that have been retained by |
| 45 |
|
the complete event selection.} |
| 46 |
|
\label{tab:hlteff} |
| 47 |
|
\end{table} |
| 48 |
|
|
| 49 |
+ |
|
| 50 |
+ |
\begin{figure}[tbp] |
| 51 |
+ |
\begin{center} |
| 52 |
+ |
\scalebox{0.7}{\includegraphics{figs/mu_isol.eps}} |
| 53 |
+ |
\caption{Muon isolation variables for the muon associated |
| 54 |
+ |
to the \W-boson decay in $2e1\mu$ events: the left plot |
| 55 |
+ |
shows the sum of calorimetric energy in a $\Delta R=0.3$ cone |
| 56 |
+ |
around the muon candidate; the right plot shows the sum of |
| 57 |
+ |
transverse momenta of tracks within a $\Delta R = 0.25$ cone around |
| 58 |
+ |
the muon candidate. The normalization of signal and background |
| 59 |
+ |
distributions is arbitrary. |
| 60 |
+ |
} |
| 61 |
+ |
\label{fig:mu_isol} |
| 62 |
+ |
\end{center} |
| 63 |
+ |
\end{figure} |
| 64 |
+ |
|
| 65 |
+ |
\begin{figure}[tb] |
| 66 |
+ |
\begin{center} |
| 67 |
+ |
\scalebox{0.6}{\includegraphics{figs/mu_SIP.eps}} |
| 68 |
+ |
\caption{ |
| 69 |
+ |
Muon impact parameter significance distribution |
| 70 |
+ |
in $2e1\mu$ events. The normalization of signal and background |
| 71 |
+ |
distributions is arbitrary. |
| 72 |
+ |
} |
| 73 |
+ |
\label{fig:mu_SIP} |
| 74 |
+ |
\end{center} |
| 75 |
+ |
\end{figure} |
| 76 |
+ |
|
| 77 |
+ |
|
| 78 |
|
\subsection{Lepton identification} |
| 79 |
|
\label{sec:leptonId} |
| 80 |
|
|
| 86 |
|
An additional isolation criterion requires that the energy |
| 87 |
|
measured in the calorimeters within a $\Delta R = 0.3$ cone around the |
| 88 |
|
muon must be smaller than 3 GeV and the sum of the $p_t$ of tracks |
| 89 |
< |
within a $\Delta R = 0.25$ cone around the muon must be smaller than 2 |
| 90 |
< |
GeV. These cuts reduce the background from muons originated in |
| 89 |
> |
within a $\Delta R = 0.25$ cone around the muon must be smaller than 2 \gev. |
| 90 |
> |
These cuts reduce the background from muons originated in |
| 91 |
|
\b-quark decays of the $\Zbbbar$ background, which are close to tracks |
| 92 |
|
and clusters from the other \b-quark decay products. |
| 93 |
|
|
| 102 |
|
variable is defined as the ratio between the measured impact parameter |
| 103 |
|
and its uncertainty: $S_{IP}=IP/\sigma_{IP}$, and is required to |
| 104 |
|
satisfy $S_{IP}<3$. This requirement is applied only for muons |
| 105 |
< |
and not for electrons. For electrons, the dominant background |
| 106 |
< |
comes from fake electrons and not from heavy quark decays. |
| 105 |
> |
and not for electrons. For electrons, a significant fraction of the |
| 106 |
> |
background comes from fake electrons and not from heavy quark decays, |
| 107 |
> |
and a cut on the impact parameter significance shows no improvement |
| 108 |
> |
in significance for the $\W\to e$ channels, as can be seen in |
| 109 |
> |
Figure~\ref{fig:wl_IP_SvsCut}. |
| 110 |
> |
|
| 111 |
> |
\begin{figure}[p] |
| 112 |
> |
\begin{center} |
| 113 |
> |
\scalebox{0.6}{\includegraphics{figs/wl_IP_eff.eps}} |
| 114 |
> |
\caption{Efficiency for signal and background as a function |
| 115 |
> |
of the cut value on the \W-boson lepton impact parameter |
| 116 |
> |
significance. All other cuts but the cut on this variable |
| 117 |
> |
are applied. |
| 118 |
> |
% Only events with 81.1 GeV $< M_Z < $ 101.1 \gev |
| 119 |
> |
% are considered. |
| 120 |
> |
} |
| 121 |
> |
\label{fig:wl_IP_eff} |
| 122 |
> |
\end{center} |
| 123 |
> |
%\end{figure} |
| 124 |
> |
|
| 125 |
> |
%\begin{figure}[bt] |
| 126 |
> |
\begin{center} |
| 127 |
> |
\scalebox{0.6}{\includegraphics{figs/wl_IP_SvsCut.eps}} |
| 128 |
> |
\caption{Signal significance as a function of the cut value on |
| 129 |
> |
the \W-boson lepton impact parameter significance. All other cuts but |
| 130 |
> |
the cut on this variable are applied. |
| 131 |
> |
% Only events with 81.1 GeV $< M_Z < $ 101.1 \gev are considered. |
| 132 |
> |
} |
| 133 |
> |
\label{fig:wl_IP_SvsCut} |
| 134 |
> |
\end{center} |
| 135 |
> |
\end{figure} |
| 136 |
|
|
| 137 |
|
|
| 138 |
+ |
\begin{table}[tbp] |
| 139 |
+ |
\begin{tabular}{|l|c|c|c|c|} \hline |
| 140 |
+ |
& $3e$ & $2e1\mu$ & $2\mu 1e$ & $3\mu$ \\ \hline \hline |
| 141 |
+ |
\multicolumn{5}{|c|}{Lepton selection} \\ \hline |
| 142 |
+ |
Electrons & \multicolumn{3}{|c|}{{\tt SimpleLoose} requirements for Z reconstruction} & \\ |
| 143 |
+ |
& \multicolumn{3}{|c|}{{\tt SimpleTight} requirements for W} & \\ \hline |
| 144 |
+ |
Muons & & \multicolumn{3}{|c|}{ Track Isolation:$ {\tt IsoTrack}(\Delta R= 0.25) < 2 \gev$} \\ |
| 145 |
+ |
& & \multicolumn{3}{|c|}{ Calorimetric Isolation:$ {\tt IsoCalo}(\Delta R = 0.3) < 5 \gev$} \\ |
| 146 |
+ |
& & \multicolumn{3}{|c|}{$S_{IP}=IP/\sigma_{IP}<3$ } \\ \hline |
| 147 |
+ |
HLT requirement & \multicolumn{2}{|c|}{ HLTSingleElectron or HLTDoubleElectronRelaxed} |
| 148 |
+ |
& \multicolumn{2}{|c|}{ HLTSingleMuonIso} \\ \hline |
| 149 |
+ |
\multicolumn{5}{|c|}{Z reconstruction} \\ \hline |
| 150 |
+ |
Lepton cuts & \multicolumn{4}{|c|}{for both Z leptons: $p_t > 15 GeV$} \\ |
| 151 |
+ |
Mass window & \multicolumn{4}{|c|}{$50 \gev < M_Z < 120 \gev $ } \\ |
| 152 |
+ |
Second Z veto & \multicolumn{4}{|c|}{No independent second Z candidate with $50 \gev < M_Z < 120 \gev $ } \\ \hline |
| 153 |
+ |
\multicolumn{5}{|c|}{W lepton selection} \\ \hline |
| 154 |
+ |
|
| 155 |
+ |
Other cuts & & & $\Delta R(\mu_Z,e_W)>0.1$ & \\ \hline |
| 156 |
+ |
Signal region & \multicolumn{4}{|c|}{$81 \gev < M_Z < 101 \gev $ } \\ \hline \hline |
| 157 |
+ |
|
| 158 |
+ |
\end{tabular} |
| 159 |
+ |
\caption{Summary of all cuts used in the WZ selection} |
| 160 |
+ |
\label{tab:allcuts} |
| 161 |
+ |
\end{table} |
| 162 |
+ |
|
| 163 |
+ |
|
| 164 |
+ |
\begin{figure}[p] |
| 165 |
+ |
\begin{center} |
| 166 |
+ |
\scalebox{0.6}{\includegraphics{figs/wlpt_cuteff.eps}} |
| 167 |
+ |
\caption{Efficiency for signal and background as a function |
| 168 |
+ |
of the cut value on the \W-boson lepton transverse momentum. |
| 169 |
+ |
All other cuts but the cut on this variable are applied. |
| 170 |
+ |
Only events with 81.1 GeV $< M_Z < $ 101.1 \gev |
| 171 |
+ |
are considered.} |
| 172 |
+ |
\label{fig:wlpt_cuteff} |
| 173 |
+ |
\end{center} |
| 174 |
+ |
%\end{figure} |
| 175 |
+ |
|
| 176 |
+ |
%\begin{figure}[bt] |
| 177 |
+ |
\begin{center} |
| 178 |
+ |
\scalebox{0.6}{\includegraphics{figs/wlpt_cutS.eps}} |
| 179 |
+ |
\caption{Signal significance as a function of the cut value on |
| 180 |
+ |
the \W-boson lepton transverse momentum. All other cuts but |
| 181 |
+ |
the cut on this variable are applied. Only events with |
| 182 |
+ |
81.1 GeV $< M_Z < $ 101.1 \gev are considered.} |
| 183 |
+ |
\label{fig:wlpt_cutS} |
| 184 |
+ |
\end{center} |
| 185 |
+ |
\end{figure} |
| 186 |
+ |
|
| 187 |
|
|
| 188 |
|
\subsection{\WZ candidate selection} |
| 189 |
|
|
| 202 |
|
rejected if a second Z candidate is found. This second Z candidate is done |
| 203 |
|
with all possible same-flavour opposite-charge combinations which are left |
| 204 |
|
after removing the two leptons already used for the first Z candidate. This |
| 205 |
< |
veto on the presence of a second Z helps to suppress $ZZ$ events. The invariant |
| 206 |
< |
mass distribution for accepted \Z candidates is shown in |
| 207 |
< |
Figure~\ref{fig:zcandidates}. |
| 205 |
> |
veto on the presence of a second Z helps to suppress $ZZ$ events. |
| 206 |
> |
%The invariant |
| 207 |
> |
%mass distribution for accepted \Z candidates is shown in |
| 208 |
> |
%Figure~\ref{fig:zcandidates}. |
| 209 |
|
|
| 210 |
|
% and the \Z mass resolution is shown in |
| 211 |
|
%Figure~\ref{fig:dzmass}. |
| 219 |
|
the additional leptons are not considered further. |
| 220 |
|
The transverse momentum of this lepton is required to be larger |
| 221 |
|
than 20 GeV. This last requirement is effective in rejecting |
| 222 |
< |
the \Zbbbar and \Zjets backgrounds, and the cut value is chosen in |
| 222 |
> |
the \Zbbbar and \Zjets backgrounds, see Figure~\ref{fig:wlpt_cuteff}, |
| 223 |
> |
and the cut value is chosen in |
| 224 |
|
the range that maximises the significance as shown in |
| 225 |
< |
Figure~\ref{fig:s_vs_wlpt}. |
| 225 |
> |
Figure~\ref{fig:wlpt_cutS}. |
| 226 |
> |
|
| 227 |
> |
An additional requirement on the isolation between electron and muons is applied |
| 228 |
> |
for the $2\mu 1e$ channel, by demanding $\Delta R$ between the electron associated |
| 229 |
> |
to the \W-decay and any of the two muons associated to the \Z-decay be greater than |
| 230 |
> |
0.1. This requirement allows to suppress the contributions of $\Z \to \mu\mu$ |
| 231 |
> |
decays, where one of the two muons radiates a photon which is reconstructed |
| 232 |
> |
as electrons, possibly after conversion, which shows up as a peak at around 60 GeV |
| 233 |
> |
in the Z mass distribution, as shown in figure~\ref{fig:Z2mu1e_60GeVPeak}. |
| 234 |
> |
|
| 235 |
> |
The summary of the selection is given in Table~\ref{tab:allcuts}. |
| 236 |
|
|
| 237 |
|
The expected number of events passing the various steps of the selection |
| 238 |
< |
is listed in Tables~\ref{tab:sel-effA} and~\ref{tab:sel-effB}. |
| 238 |
> |
is listed in Tables~\ref{tab:sel-effA}. |
| 239 |
|
Table~\ref{tab:wz-effimatrix} lists the final selection efficiency for |
| 240 |
|
the different generated \W and \Z decays. It can be seen there that \WZ\ |
| 241 |
|
events with both the \W and the \Z boson decaying into electrons or muons |
| 246 |
|
to the \pt cut on the third lepton, since the \pt spectrum of electrons or |
| 247 |
|
muons from $W \to \tau \to e/\mu$ decays is softer. |
| 248 |
|
|
| 249 |
+ |
Tables~ref\label{tab:wz-matcheffi-Zee} and \label{tab:wz-matcheffi-Zmumu} show |
| 250 |
+ |
the fraction of reconstructed \WZ events with with correclty matched leptons |
| 251 |
+ |
It is in particular worth mentioning that the lepton associated to the \W-decay |
| 252 |
+ |
is correclty matched to the true lepton from the \W-decay in more than 90\% of |
| 253 |
+ |
the cases even for events with several lepton candidates available to be associated |
| 254 |
+ |
to the \W-decay. The choice to take the candidate with the leading \pt is therefore |
| 255 |
+ |
justified. |
| 256 |
+ |
|
| 257 |
|
\begin{table}[p] |
| 258 |
|
\begin{center} |
| 259 |
|
|
| 260 |
+ |
|
| 261 |
+ |
|
| 262 |
+ |
|
| 263 |
|
\begin{tabular}{lcccc} \hline |
| 264 |
< |
Step & WZ & Z+jets & TTbar+jets & bbll\\ \hline |
| 265 |
< |
All events & 546 & 1.2679e+06 & 17556.1 & 72770.4 \\ |
| 266 |
< |
Found $Z \to ee$ & 219.517 (40.2045 \%) & 520695 (41.0674 \%) & 3474.61 (19.7914 \%) & 29563.3 (40.6254 \%) \\ |
| 267 |
< |
Z loose electron ID & 219.517 (100 \%) & 520695 (100 \%) & 3474.61 (100 \%) & 29563.3 (100 \%) \\ |
| 268 |
< |
Z Lepton Pt cut & 216.371 (98.5671 \%) & 515556 (99.0131 \%) & 3289.22 (94.6645 \%) & 29109.9 (98.4665 \%) \\ |
| 269 |
< |
Z Lepton $eta$ cut & 216.371 (100 \%) & 515556 (100 \%) & 3289.22 (100 \%) & 29109.9 (100 \%) \\ |
| 270 |
< |
Z Lepton IP cut & 206.797 (95.5751 \%) & 492205 (95.4707 \%) & 3011.11 (91.5448 \%) & 27833.5 (95.6153 \%) \\ |
| 271 |
< |
Found $W \to e$ & 42.8968 (20.7434 \%) & 301.116 (0.061177 \%) & 14.8797 (0.494158 \%) & 173.054 (0.621745 \%) \\ |
| 272 |
< |
W Lepton $\eta$ cut & 42.8968 (100 \%) & 301.116 (100 \%) & 14.8797 (100 \%) & 173.054 (100 \%) \\ |
| 143 |
< |
W Lepton Pt cut & 35.6425 (83.0889 \%) & 86.9864 (28.8879 \%) & 9.30549 (62.5383 \%) & 23.9385 (13.833 \%) \\ |
| 144 |
< |
W tight electron ID & 35.6425 (100 \%) & 86.9864 (100 \%) & 9.30549 (100 \%) & 23.9385 (100 \%) \\ |
| 145 |
< |
Passes HLT & 35.4852 (99.5587 \%) & 85.9427 (98.8002 \%) & 9.30549 (100 \%) & 23.4938 (98.1424 \%) \\ |
| 146 |
< |
Z mass window & 31.7106 (5.8078 \%) & 54.1554 (0.00427126 \%) & 3.2585 (0.0185605 \%) & 17.046 (0.0234243\%) \\ |
| 264 |
> |
\multicolumn{5}{c}{ {\bf $3e$ Channel}} \\ \hline \hline |
| 265 |
> |
Step & WZ & bbll & Z+jets & TTbar+jets\\ \hline |
| 266 |
> |
All events & 546 & 72770.4 & 1.2679e+06 & 17556.1 \\ |
| 267 |
> |
Found $Z \to ee$ & 204.969 (37.5401 \%) & 27800.5 (38.203 \%) & 502344 (39.62 \%) & 2920.59 (16.6357 \%) \\ |
| 268 |
> |
Found $W \to e$ & 41.9925 (20.4872 \%) & 171.053 (0.615286 \%) & 309.563 (0.0616238 \%) & 13.8293 (0.473511 \%) \\ |
| 269 |
> |
W Lepton Pt cut & 34.8561 (83.0056 \%) & 23.7161 (13.8648 \%) & 86.7924 (28.037 \%) & 8.25515 (59.6931 \%) \\ |
| 270 |
> |
Passes HLT & 34.7185 (99.6052 \%) & 23.5679 (99.375 \%) & 86.7924 (100 \%) & 8.25515 (100 \%) \\ |
| 271 |
> |
Z mass window & 31.5533 (90.8834 \%) & 17.4906 (74.2138 \%) & 51.8927 (59.7894 \%) & 3.2585 (39.4724 \%) \\ \hline |
| 272 |
> |
Overall efficiency & 5.77899 \% & 0.0240354 \% & 0.00409279 \% & 0.0185605 \% \\ |
| 273 |
|
\hline |
| 274 |
|
\end{tabular} |
| 149 |
– |
|
| 150 |
– |
|
| 275 |
|
\begin{tabular}{lcccc} \hline |
| 276 |
< |
Step & WZ & Z+jets & TTbar+jets & bbll\\ \hline |
| 277 |
< |
All events & 546 & 1.2679e+06 & 17556.1 & 72770.4 \\ |
| 278 |
< |
Found $Z \to ee$ & 219.517 (40.2045 \%) & 520695 (41.0674 \%) & 3474.61 (19.7914 \%) & 29563.3 (40.6254 \%) \\ |
| 279 |
< |
Z electron ID loose & 219.517 (100 \%) & 520695 (100 \%) & 3474.61 (100 \%) & 29563.3 (100 \%) \\ |
| 280 |
< |
Z Lepton Pt cut & 216.371 (98.5671 \%) & 515556 (99.0131 \%) & 3289.22 (94.6645 \%) & 29109.9 (98.4665 \%) \\ |
| 281 |
< |
Z Lepton $eta$ cut & 216.371 (100 \%) & 515556 (100 \%) & 3289.22 (100 \%) & 29109.9 (100 \%) \\ |
| 282 |
< |
Z Lepton IP cut & 206.797 (95.5751 \%) & 492205 (95.4707 \%) & 3011.11 (91.5448 \%) & 27833.5 (95.6153 \%) \\ |
| 283 |
< |
Found $W \to \mu$ & 57.1892 (27.6547 \%) & 5982.86 (1.21552 \%) & 815.122 (27.0705 \%) & 3808.22 (13.6821 \%) \\ |
| 284 |
< |
W Lepton $\eta$ cut & 57.1695 (99.9656 \%) & 5964.1 (99.6865 \%) & 815.122 (100 \%) & 3805.62 (99.9319 \%) \\ |
| 161 |
< |
W $\mu$ isolation & 52.1367 (91.1967 \%) & 2754.29 (46.1811 \%) & 85.5097 (10.4904 \%) & 1328.18 (34.9004 \%) \\ |
| 162 |
< |
W muon isolation & 39.8889 (76.5083 \%) & 22.2149 (0.806557 \%) & 18.8521 (22.0468 \%) & 16.6013 (1.24993 \%) \\ |
| 163 |
< |
Passes HLT & 38.7683 (97.1907 \%) & 21.2077 (95.466 \%) & 16.5627 (87.8556 \%) & 16.1566 (97.3214 \%) \\ |
| 164 |
< |
Z mass window & 34.6399 (6.34429 \%) & 17.3805 (0.00137081 \%) & 5.4405 (0.0309891 \%) & 14.0814 (0.0193505 \%) \\ |
| 276 |
> |
\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 |
|
\hline |
| 286 |
|
\end{tabular} |
| 287 |
|
|
| 288 |
|
\begin{tabular}{lcccc} \hline |
| 289 |
< |
Step & WZ & Z+jets & TTbar+jets & bbll\\ \hline |
| 290 |
< |
All events & 546 & 1.2679e+06 & 17556.1 & 72770.4 \\ |
| 291 |
< |
Found $Z \to \mu\mu$ & 326.484 (59.7955 \%) & 748256 (59.0152 \%) & 14081.6 (80.2087 \%) & 43207.1 (59.3746 \%) \\ |
| 292 |
< |
Z muon isolation & 282.27 (86.4575 \%) & 669556 (89.4822 \%) & 4201.52 (29.837 \%) & 37959.1 (87.8538 \%) \\ |
| 293 |
< |
Z Lepton $eta$ cut & 282.27 (100 \%) & 669547 (99.9987 \%) & 4200.47 (99.975 \%) & 37959.1 (99.9998 \%) \\ |
| 294 |
< |
Z Lepton Pt cut & 274.249 (97.1584 \%) & 657267 (98.1659 \%) & 3626.81 (86.3429 \%) & 36945.8 (97.3306 \%) \\ |
| 295 |
< |
Z Lepton IP cut & 249.792 (91.0824 \%) & 603257 (91.7827 \%) & 3125.35 (86.1737 \%) & 33937.7 (91.8581 \%) \\ |
| 296 |
< |
Found $W \to e$ & 51.9401 (20.7933 \%) & 797.766 (0.132243 \%) & 20.4415 (0.654055 \%) & 228.342 (0.672826 \%) \\ |
| 297 |
< |
W Lepton $\eta$ cut & 51.9401 (100 \%) & 797.766 (100 \%) & 20.4415 (100 \%) & 228.342 (100 \%) \\ |
| 298 |
< |
W tight electron ID & 51.9401 (100 \%) & 797.766 (100 \%) & 20.4415 (100 \%) & 228.342 (100 \%) \\ |
| 179 |
< |
W Lepton Pt cut & 43.2703 (83.3081 \%) & 519.647 (65.1378 \%) & 15.0823 (73.7829 \%) & 55.14 (24.148 \%)\\ |
| 180 |
< |
Passes HLT & 41.8745 (96.7742 \%) & 490.859 (94.46 \%) & 13.533 (89.7275 \%) & 54.2506 (98.3871 \%) \\ |
| 181 |
< |
Z mass window & 37.5298 (6.87358 \%) & 63.522 (0.00501 \%) & 5.02282 (0.02861 \%) & 20.0105 (0.0274981 \%) \\ |
| 289 |
> |
\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 |
|
\hline |
| 300 |
|
\end{tabular} |
| 301 |
|
|
| 302 |
+ |
|
| 303 |
|
\begin{tabular}{lcccc} \hline |
| 304 |
< |
Step & WZ & Z+jets & TTbar+jets & bbll\\ \hline |
| 305 |
< |
All events & 546 & 1.2679e+06 & 17556.1 & 72770.4 \\ |
| 306 |
< |
Found $Z \to \mu\mu$ & 326.484 (59.7955 \%) & 748256 (59.0152 \%) & 14081.6 (80.2087 \%) & 43207.1 (59.3746 \%) \\ |
| 307 |
< |
Z muon isolation & 282.27 (86.4575 \%) & 669556 (89.4822 \%) & 4201.52 (29.837 \%) & 37959.1 (87.8538 \%) \\ |
| 308 |
< |
Z Lepton $eta$ cut & 282.27 (100 \%) & 669547 (99.9987 \%) & 4200.47 (99.975 \%) & 37959.1 (99.9998 \%) \\ |
| 309 |
< |
Z Lepton Pt cut & 274.249 (97.1584 \%) & 657267 (98.1659 \%) & 3626.81 (86.3429 \%) & 36945.8 (97.3306 \%) \\ |
| 310 |
< |
Z Lepton IP cut & 249.792 (91.0824 \%) & 603257 (91.7827 \%) & 3125.35 (86.1737 \%) & 33937.7 (91.8581 \%) \\ |
| 311 |
< |
Found $W \to \mu$ & 73.015 (29.2303 \%) & 7135.7 (1.18286 \%) & 774.076 (24.7677 \%) & 4435.51 (13.0696 \%) \\ |
| 312 |
< |
W Lepton $\eta$ cut & 72.956 (99.9192 \%) & 7110.07 (99.6409 \%) & 774.076 (100 \%) & 4432.32 (99.9282 \%) \\ |
| 195 |
< |
W $\mu$ isolation & 66.724 (91.4578 \%) & 3382.99 (47.5803 \%) & 78.3017 (10.1155 \%) & 1560.97 (35.2178 \%) \\ |
| 196 |
< |
W muon isolation & 50.1118 (75.1031 \%) & 6.25174 (0.184799 \%) & 5.8096 (7.41951 \%) & 20.6775 (1.32466 \%) \\ |
| 197 |
< |
Passes HLT & 49.7972 (99.3723 \%) & 6.25174 (100 \%) & 5.8096 (100 \%) & 20.6034 (99.6416 \%) \\ |
| 198 |
< |
Z mass window & 45.1576 (8.27062 \%) & 4.9976 (0.000394162 \%) & 1.683 (0.00958638 \%) & 18.3059 (0.0251557 \%) \\ |
| 304 |
> |
\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 |
|
\hline |
| 314 |
|
\end{tabular} |
| 315 |
+ |
|
| 316 |
+ |
|
| 317 |
|
\caption{Expected number of signal and background events passing the different |
| 318 |
< |
selections steps in the \WZ, \ttbar and \Zbbbar samples for an integrated luminosity |
| 318 |
> |
selections steps in the \WZ, \Zbbbar, \Zjets and \ttjets samples for an integrated luminosity |
| 319 |
|
of 1 \invfb.} |
| 320 |
|
\label{tab:sel-effA} |
| 321 |
|
\end{center} |
| 322 |
|
\end{table} |
| 323 |
|
|
| 324 |
+ |
\begin{table}[p] |
| 325 |
+ |
\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 |
+ |
%\end{table} |
| 359 |
+ |
%\begin{table}[tbp] |
| 360 |
+ |
\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 |
|
|
| 210 |
– |
\subsection{Signal extraction} |
| 409 |
|
|
| 410 |
|
|
| 411 |
< |
\subsection{Systematic uncertainties} |
| 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 |
> |
|
| 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.} |
| 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 |
+ |
|
