ViewVC Help
View File | Revision Log | Show Annotations | Root Listing
root/cvsroot/UserCode/Vuko/Notes/WZCSA07/selection.tex
(Generate patch)

Comparing UserCode/Vuko/Notes/WZCSA07/selection.tex (file contents):
Revision 1.6 by vuko, Fri Jun 20 13:50:28 2008 UTC vs.
Revision 1.13 by ymaravin, Mon Jun 23 13:39:58 2008 UTC

# Line 1 | Line 1
1   \section{Event reconstruction}
2   \label{sec:eventReconstruction}
3  
4 < The four possible final states of \WZ
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:
4 > We categorize \WZ\ three-lepton final state as following
5   \begin{itemize}
6   \item $3e$: for \WZ events with $\W \to e \nu$ and $\Z\to \epem$.
7   \item $2e1\mu$: for \WZ events with $\W \to \mu \nu$ and $\Z\to \epem$.
# Line 19 | Line 16 | Events stemming from the three-lepton fi
16   are collected by the electron and/or muon triggers. For each channel,
17   a minimun number of HLT requirements is chosen while keeping
18   the HLT efficiency for selected events close to 100\%. The same
19 < HLT requirements are used for channels with the same Z decay mode:
19 > HLT requirements are used for channels with the same \Z decay mode:
20   \begin{itemize}
21   \item for $3e$ and $2e1\mu$: HLTSingleElectron or HLTDoubleElectronRelaxed
22   \item for $2\mu1e$ and $3\mu$: HLTSingleMuonIso
# Line 27 | Line 24 | HLT requirements are used for channels w
24   The HLT efficiencies for all modes for events passing the full
25   selection described in this section are given in table~\ref{tab:hlteff}.
26  
30
27   \begin{table}[tbph]
28   \begin{center}
29  
# Line 41 | Line 37 | $3\mu$     &   HLTSingleMuonIso
37  
38   \end{center}
39   \caption{HLT Efficiencies, in percent, for all
40 <  the events in the generated phase space for events retained  by
40 >  the events in the generated phase space that have been retained  by
41    the complete event selection.}
42   \label{tab:hlteff}
43   \end{table}
44  
45 +
46 + \begin{figure}[tbp]
47 +  \begin{center}
48 +  \scalebox{0.7}{\includegraphics{figs/mu_isol.eps}}
49 +  \caption{Muon isolation variables for the muon associated
50 +    to the \W boson decay in $2e1\mu$ events: in the left plot
51 +    we illustrate the sum of calorimetric energy in a $\Delta R=0.3$ cone
52 +    around the muon candidate; in the right plot we display the sum of
53 +    transverse momenta of tracks within a $\Delta R = 0.25$ cone around
54 +    the muon candidate. The normalization of signal and background
55 +    distributions is arbitrary.
56 + }
57 +  \label{fig:mu_isol}
58 +  \end{center}
59 + \end{figure}
60 +
61 + \begin{figure}[tb]
62 +  \begin{center}
63 +  \scalebox{0.6}{\includegraphics{figs/mu_SIP.eps}}
64 +  \caption{
65 +    Muon impact parameter significance distribution
66 +    in $2e1\mu$ events. The normalization of signal and background
67 +    distributions is arbitrary.
68 +  }
69 +  \label{fig:mu_SIP}
70 +  \end{center}
71 + \end{figure}
72 +
73 +
74   \subsection{Lepton identification}
75   \label{sec:leptonId}
76  
# Line 53 | Line 78 | The requirements used for electron ident
78   in~\cite{noteElectronID}.
79  
80   Muon candidates are selected from global muons, which are reconstructed
81 < combining measurements in the muon chambers and the central tracker.
82 < An additional isolation criterion requires that the energy
81 > by combining measurements in the muon chambers and the central tracker.
82 > An additional isolation criterion is imposed to require the energy
83   measured in the calorimeters within a $\Delta R = 0.3$ cone around the
84 < muon must be smaller than 3 GeV and the sum of the $p_t$ of tracks
85 < within a $\Delta R = 0.25$ cone around the muon must be smaller than 2
86 < GeV. These cuts reduce the background from muons originated in
84 > muon to be smaller than 3 GeV and the sum of the $p_T$ of tracks
85 > within a $\Delta R = 0.25$ cone around the muon must be smaller than 2 GeV.
86 > These cuts reduce the background from muons originated in
87   \b-quark decays of the $\Zbbbar$ background, which are close to tracks
88   and clusters from the other \b-quark decay products.
89  
# Line 69 | Line 94 | and clusters from the other \b-quark dec
94  
95   The significance of the muon impact parameter in the plane
96   transverse to the beam, $S_{IP}$, discriminates against leptons from
97 < heavy-quark decays in all Standard Model background processes. This
97 > heavy-quark decays in all standard model background processes. This
98   variable is defined as the ratio between the measured impact parameter
99   and its uncertainty: $S_{IP}=IP/\sigma_{IP}$, and is required to
100 < satisfy $S_{IP}<3$. This requirement is applied only for muons
101 < and not for electrons. For electrons, the dominant background
102 < comes from fake electrons and not from heavy quark decays.
100 > satisfy $S_{IP}<3$. This requirement is applied only for muon candidates
101 > and not for electrons. For electron candidates, a significant fraction of the
102 > background comes from misidentified light quark jets. Thus,
103 > the requirement on the impact parameter significance does not
104 > increase the significance of the $\W\to e$ channels, as can be seen in
105 > Fig.~\ref{fig:wl_IP_SvsCut}.
106 >
107 > \begin{figure}[p]
108 >  \begin{center}
109 >  \scalebox{0.6}{\includegraphics{figs/wl_IP_eff.eps}}
110 >  \caption{Efficiency for signal and background as a function
111 >    of the requirement on the \W-boson lepton impact parameter
112 >    significance. All other criteria but the one on impact parameter
113 >    significance are applied.
114 > %    Only events with 81.1 GeV $< M_Z < $ 101.1 \gev
115 > %    are considered.
116 >  }
117 >  \label{fig:wl_IP_eff}
118 >  \end{center}
119 > %\end{figure}
120  
121 + %\begin{figure}[bt]
122 +  \begin{center}
123 +  \scalebox{0.6}{\includegraphics{figs/wl_IP_SvsCut.eps}}
124 +  \caption{Signal significance as a function of requirement on
125 +    the \W-boson lepton impact parameter significance. All other criteria but
126 +    the requirement on the impact parameter significance are applied.
127 + %    Only events with 81.1 GeV $< M_Z < $ 101.1 \gev are considered.
128 +  }
129 +  \label{fig:wl_IP_SvsCut}
130 +  \end{center}
131 + \end{figure}
132 +
133 +
134 + \begin{table}[tbp]
135 + \begin{tabular}{|l|c|c|c|c|} \hline
136 +              &  $3e$ & $2e1\mu$ & $2\mu 1e$ & $3\mu$ \\ \hline \hline
137 + \multicolumn{5}{|c|}{Lepton selection} \\ \hline
138 + Electrons     &   \multicolumn{3}{|c|}{{\tt SimpleLoose} requirements for \Z reconstruction} & \\
139 +              &   \multicolumn{3}{|c|}{{\tt SimpleTight} requirements for \W} &  \\ \hline
140 + Muons         &  &  \multicolumn{3}{|c|}{ Track Isolation:$ {\tt IsoTrack}(\Delta R= 0.25) < 2 \gev$}  \\
141 +              &  &  \multicolumn{3}{|c|}{ Calorimetric Isolation:$  {\tt IsoCalo}(\Delta R = 0.3)  < 5 \gev$}  \\
142 +              &  &  \multicolumn{3}{|c|}{$S_{IP}=IP/\sigma_{IP}<3$ }  \\ \hline
143 + HLT requirement & \multicolumn{2}{|c|}{ HLTSingleElectron or HLTDoubleElectronRelaxed}
144 +                & \multicolumn{2}{|c|}{  HLTSingleMuonIso} \\ \hline
145 + \multicolumn{5}{|c|}{\Z reconstruction} \\ \hline
146 + Lepton cuts   &  \multicolumn{4}{|c|}{for both \Z leptons: $p_T > 15$ GeV} \\
147 + Mass window   &  \multicolumn{4}{|c|}{$50 \gev < M_Z < 120 \gev $ } \\
148 + Second \Z veto &  \multicolumn{4}{|c|}{No independent second \Z candidate with $50 \gev < M_Z < 120 \gev $ } \\ \hline
149 + \multicolumn{5}{|c|}{\W lepton selection} \\ \hline
150 +
151 + Other cuts    &     &        & $\Delta R(\mu_Z,e_W)>0.1$ &  \\ \hline
152 + Signal region  &    \multicolumn{4}{|c|}{$81 \gev < M_Z < 101 \gev $ } \\ \hline \hline
153 +
154 + \end{tabular}
155 + \caption{Summary of the criteria we use to select \WZ\ final state}
156 + \label{tab:allcuts}
157 + \end{table}
158 +
159 +
160 + \begin{figure}[p]
161 +  \begin{center}
162 +  \scalebox{0.6}{\includegraphics{figs/wlpt_cuteff.eps}}
163 +  \caption{Efficiency for signal and background as a function
164 +    of the cut value on the \W-boson lepton transverse momentum.
165 +    All other cuts but the cut on this variable are applied.
166 +    Only events with 81.1 GeV $< M_Z < $ 101.1 \gev
167 +    are considered.}
168 +  \label{fig:wlpt_cuteff}
169 +  \end{center}
170 + %\end{figure}
171 +
172 + %\begin{figure}[bt]
173 +  \begin{center}
174 +  \scalebox{0.6}{\includegraphics{figs/wlpt_cutS.eps}}
175 +  \caption{Signal significance as a function of the cut value on
176 +    the \W-boson lepton transverse momentum. All other cuts but
177 +    the cut on this variable are applied. Only events with
178 +    81.1 GeV $< M_Z < $ 101.1 \gev are considered.}
179 +  \label{fig:wlpt_cutS}
180 +  \end{center}
181 + \end{figure}
182  
183  
184   \subsection{\WZ candidate selection}
185  
186   Events are accepted if they contain at least three charged leptons,
187 < either electrons or muons, with $p_t > 15\,\mathrm{GeV}$ and $| \eta | < 2.5$ for
188 < electrons,$| \eta | < 2.4$ for muons.
86 < as discussed in~\ref{sec:leptonId}.
187 > either electrons or muons, with $p_T > 15\,\mathrm{GeV}$ and $| \eta | < 2.5$ for
188 > electrons,$| \eta | < 2.4$ for muons, as discussed in Section~\ref{sec:leptonId}.
189  
190   The \WZ candidate selection proceeds from building all possible
191   \Z-boson candidates from same-flavour opposite-charge lepton pairs.
192 < For $\Z \to ee$ decays, electrons have to fullfil the loose requirements
192 > For $\Z \to ee$ decays, electron candidates have to fulfill the loose requirements
193   defined in~\cite{noteElectronID}.
194  
195 < Events are retained if the mass of this \Z-boson candidate is
196 < within 20 GeV of the Z-boson mass,$m_Z$. The event is
197 < rejected if a second Z candidate is found. This second Z candidate is done
198 < with all possible same-flavour opposite-charge combinations which are left
199 < after removing the two leptons already used for the first Z candidate. This
200 < veto on the presence of a second Z helps to suppress $ZZ$ events. The invariant
201 < mass distribution for accepted \Z candidates is shown in
202 < Figure~\ref{fig:zcandidates}.
195 > Events are retained if the mass of the \Z boson candidate is
196 > within 20 GeV of the \Z boson mass, $m_Z$. The event is
197 > rejected if a second \Z candidate is found. This second \Z boson candidate is formed
198 > using all possible same-flavour opposite-charge combinations which are left
199 > after removing the two leptons already used for the first \Z boson candidate. This
200 > secondary \Z boson veto helps to suppress $\Z\Z$ events.
201 > %The invariant
202 > %mass distribution for accepted \Z candidates is shown in
203 > %Figure~\ref{fig:zcandidates}.
204  
205   % and the \Z mass resolution is shown in
206   %Figure~\ref{fig:dzmass}.
207  
208 < After the \Z-boson candidate is identified, the lepton associated
209 < to the  \W-boson decay is chosen from the remaining electrons and muons
210 < in the event that have not been used for reconstructing the \Z-boson.
211 < Electrons are required to pass the tight criteria described in
212 < \cite{noteElectronID}.  If the event contains more than three leptons,
213 < the highest $p_t$ is chosen as the one from the \W-boson decay, and
214 < the additional leptons are not considered further.
215 < The transverse momentum of this lepton is required to be larger
216 < than 20 GeV. This last requirement is effective in rejecting
217 < the \Zbbbar and \Zjets backgrounds, and the cut value is chosen in
218 < the range that maximises the significance as shown in
219 < Figure~\ref{fig:s_vs_wlpt}.
220 <
221 < An additional requirement on the isolation between electron and muons is applied
222 < for the $2\mu 1e$ channel, by demanding $\Delta R$ between the electron associated
120 < to the \W-decay and any of the two muons associated to the \Z-decay be greater than
121 < 0.1. This requirement allows to suppress the contributions of $\Z \to \mu\mu$
208 > After the \Z boson candidate is identified, the remaining leptons in the event
209 > are required to pass the tight criteria described in~\cite{noteElectronID}.
210 > If more than one lepton candidate satisfies the tight requirements, the one with the
211 > highest $p_T$ is associated with \W boson decay. This lepton's $p_T$ is effective
212 > discriminant against \Zbbbar and \Zjets production (see Fig.~\ref{fig:wlpt_cuteff}).
213 > We require the transverse momentum to exceed 20 GeV, as it maximizes
214 > the significance of the \WZ\ signal with respect to background as shown in
215 > Fig.~\ref{wlpt_cuteff}.
216 >
217 > An additional requirement on the isolation between electron and muon candidates is applied
218 > for the $2\mu 1e$ channel, by demanding the value of $\Delta R$ between the electron
219 > candidate associated with the \W boson decay and any of the two muons associated with
220 > the \Z boson decay to be greater than 0.1.
221 >
222 > This requirement allows suppressing the contribution of $\Z \to \mu\mu$
223   decays, where one of the two muons radiates a photon which is reconstructed
224 < as electrons, possibly after conversion, which shows up as a peak at  around 60 GeV
225 < in the Z mass distribution, as shown in figure~\ref{fig:Z2mu1e_60GeVPeak}.
224 > as an electron, possibly after conversion. This can be seen as a peak in the dimuon
225 > invariant mass at  around 60 GeV in Fig.~\ref{fig:Z2mu1e_60GeVPeak}.
226  
227 < The expected number of events passing the various steps of the selection
228 < is listed in Tables~\ref{tab:sel-effA} and~\ref{tab:sel-effB}.
229 < Table~\ref{tab:wz-effimatrix} lists the final selection efficiency for
230 < the different generated \W and \Z decays. It can be seen there that \WZ\
231 < events with both the \W and the \Z boson decaying into electrons or muons
232 < almost always get reconstructed with the correct flavour. It is to be
233 < noted in addition that each of our four selection channels gets a small
234 < contribution from $W \to \tau \to e/\mu$ decays as one would expect. The
235 < selection efficiency for these events is however smaller which is mostly due
236 < to the \pt cut on the third lepton, since the \pt spectrum of electrons or
237 < muons from $W \to \tau \to e/\mu$ decays is softer.
227 > The summary of the selection criteria is given in Table~\ref{tab:allcuts}.
228 >
229 > The expected number of the events satisfying the sequential steps of the selection
230 > is listed in Tables~\ref{tab:sel-effA}.  
231 > In Table~\ref{tab:wz-effimatrix} we list the total selection efficiency for  different
232 > \W and \Z boson decay modes. It can be seen lepton candidates from \W and \Z
233 > boson decays are almost always are reconstructed with the correct flavor. As expected,
234 > there is a small contribution from $\W \to \tau \nu_\tau \to \ell \nu_\ell \nu_\tau$
235 > decays. However, this contribution is suppressed, mostly due to $p_T$ requirement
236 > on the third lepton, as leptons from $\tau$ decays are not as energetic as those from
237 > $\W \to \ell \nu$ processes.
238 >
239 > In Tables~ref\label{tab:wz-matcheffi-Zee} and \label{tab:wz-matcheffi-Zmumu} we
240 > display the fraction of reconstructed \WZ events with correctly-matched leptons.
241 > It can be seen that the lepton associated with the \W boson decay is correctly matched
242 > to the true Monte Carlo lepton from the \W boson decay in more than 90\% of
243 > the cases, even for events with several lepton candidates available to be associated
244 > to the \W boson decay. The choice to take the lepton candidate with the leading $p_T$ is,
245 > therefore, justified.
246  
247   \begin{table}[p]
248    \begin{center}
249  
141 \begin{tabular}{lcccc} \hline
142 Step   & WZ  & Z+jets  & TTbar+jets  & bbll\\ \hline
143 All events       & 546   & 1.2679e+06    & 17556.1       & 72770.4 \\
144 Found $Z \to ee$         & 219.517 (40.2045 \%)  & 520695 (41.0674 \%)   & 3474.61 (19.7914 \%)  & 29563.3 (40.6254 \%) \\
145 Z loose electron ID      & 219.517 (100 \%)      & 520695 (100 \%)       & 3474.61 (100 \%)      & 29563.3 (100 \%) \\
146 Z Lepton Pt cut          & 216.371 (98.5671 \%)  & 515556 (99.0131 \%)   & 3289.22 (94.6645 \%)  & 29109.9 (98.4665 \%) \\
147 Z Lepton $eta$ cut       & 216.371 (100 \%)      & 515556 (100 \%)       & 3289.22 (100 \%)      & 29109.9 (100 \%) \\
148 Z Lepton IP cut          & 206.797 (95.5751 \%)  & 492205 (95.4707 \%)   & 3011.11 (91.5448 \%)  & 27833.5 (95.6153 \%) \\
149 Found $W \to e$          & 42.8968 (20.7434 \%)  & 301.116 (0.061177 \%)         & 14.8797 (0.494158 \%)         & 173.054 (0.621745 \%) \\
150 W Lepton $\eta$ cut      & 42.8968 (100 \%)      & 301.116 (100 \%)      & 14.8797 (100 \%)      & 173.054 (100 \%) \\
151 W Lepton Pt cut          & 35.6425 (83.0889 \%)  & 86.9864 (28.8879 \%)  & 9.30549 (62.5383 \%)  & 23.9385 (13.833 \%) \\
152 W tight electron ID      & 35.6425 (100 \%)      & 86.9864 (100 \%)      & 9.30549 (100 \%)      & 23.9385 (100 \%) \\
153 Passes HLT               & 35.4852 (99.5587 \%)  & 85.9427 (98.8002 \%)  & 9.30549 (100 \%)      & 23.4938 (98.1424 \%) \\
154 Z mass window    & 31.7106 (5.8078 \%)   & 54.1554 (0.00427126 \%)       & 3.2585 (0.0185605 \%)         & 17.046 (0.0234243\%) \\
155 \hline
156 \end{tabular}
250  
251  
159 \begin{tabular}{lcccc} \hline
160 Step   & WZ  & Z+jets  & TTbar+jets  & bbll\\ \hline
161 All events       & 546   & 1.2679e+06    & 17556.1       & 72770.4 \\
162 Found $Z \to ee$         & 219.517 (40.2045 \%)  & 520695 (41.0674 \%)   & 3474.61 (19.7914 \%)  & 29563.3 (40.6254 \%) \\
163 Z electron ID loose      & 219.517 (100 \%)      & 520695 (100 \%)       & 3474.61 (100 \%)      & 29563.3 (100 \%) \\
164 Z Lepton Pt cut          & 216.371 (98.5671 \%)  & 515556 (99.0131 \%)   & 3289.22 (94.6645 \%)  & 29109.9 (98.4665 \%) \\
165 Z Lepton $eta$ cut       & 216.371 (100 \%)      & 515556 (100 \%)       & 3289.22 (100 \%)      & 29109.9 (100 \%) \\
166 Z Lepton IP cut          & 206.797 (95.5751 \%)  & 492205 (95.4707 \%)   & 3011.11 (91.5448 \%)  & 27833.5 (95.6153 \%) \\
167 Found $W \to \mu$        & 57.1892 (27.6547 \%)  & 5982.86 (1.21552 \%)  & 815.122 (27.0705 \%)  & 3808.22 (13.6821 \%) \\
168 W Lepton $\eta$ cut      & 57.1695 (99.9656 \%)  & 5964.1 (99.6865 \%)   & 815.122 (100 \%)      & 3805.62 (99.9319 \%) \\
169 W $\mu$ isolation        & 52.1367 (91.1967 \%)  & 2754.29 (46.1811 \%)  & 85.5097 (10.4904 \%)  & 1328.18 (34.9004 \%) \\
170 W muon isolation         & 39.8889 (76.5083 \%)  & 22.2149 (0.806557 \%)         & 18.8521 (22.0468 \%)  & 16.6013 (1.24993 \%) \\
171 Passes HLT               & 38.7683 (97.1907 \%)  & 21.2077 (95.466 \%)   & 16.5627 (87.8556 \%)  & 16.1566 (97.3214 \%) \\
172 Z mass window    & 34.6399 (6.34429 \%)  & 17.3805 (0.00137081 \%)       & 5.4405 (0.0309891 \%)         & 14.0814 (0.0193505 \%) \\
173 \hline
174 \end{tabular}
252  
253 < \begin{tabular}{lcccc} \hline
254 < Step   & WZ  & Z+jets  & TTbar+jets  & bbll\\ \hline
255 < All events       & 546   & 1.2679e+06    & 17556.1       & 72770.4 \\
256 < Found $Z \to \mu\mu$     & 326.484 (59.7955 \%)  & 748256 (59.0152 \%)   & 14081.6 (80.2087 \%)  & 43207.1 (59.3746 \%) \\
257 < Z muon isolation                 & 282.27 (86.4575 \%)   & 669556 (89.4822 \%)   & 4201.52 (29.837 \%)   & 37959.1 (87.8538 \%) \\
258 < Z Lepton $eta$ cut       & 282.27 (100 \%)       & 669547 (99.9987 \%)   & 4200.47 (99.975 \%)   & 37959.1 (99.9998 \%) \\
259 < Z Lepton Pt cut                  & 274.249 (97.1584 \%)  & 657267 (98.1659 \%)   & 3626.81 (86.3429 \%)  & 36945.8 (97.3306 \%) \\
260 < Z Lepton IP cut                  & 249.792 (91.0824 \%)  & 603257 (91.7827 \%)   & 3125.35 (86.1737 \%)  & 33937.7 (91.8581 \%) \\
261 < Found $W \to e$          & 51.9401 (20.7933 \%)  & 797.766 (0.132243 \%)         & 20.4415 (0.654055 \%)         & 228.342 (0.672826 \%) \\
262 < W Lepton $\eta$ cut      & 51.9401 (100 \%)      & 797.766 (100 \%)      & 20.4415 (100 \%)      & 228.342 (100 \%) \\
263 < W tight electron ID              & 51.9401 (100 \%)      & 797.766 (100 \%)      & 20.4415 (100 \%)      & 228.342 (100 \%) \\
264 < W Lepton Pt cut                  & 43.2703 (83.3081 \%)  & 519.647 (65.1378 \%)  & 15.0823 (73.7829 \%)  & 55.14 (24.148 \%)\\
265 < Passes HLT               & 41.8745 (96.7742 \%)  & 490.859 (94.46 \%)    & 13.533 (89.7275 \%)   & 54.2506 (98.3871 \%) \\
266 < Z mass window    & 37.5298 (6.87358 \%)  & 63.522 (0.00501 \%)   & 5.02282 (0.02861 \%)  & 20.0105 (0.0274981 \%) \\
253 > \begin{tabular}{lcc|cc|cc|cc|c} \hline \hline
254 > \multicolumn{9}{c}{ {\bf $3e$ Channel}} \\ \hline  \hline
255 > Step                                 & \WZ  & $\epsilon$ & $b\bar{b}\ell\ell$  & $\epsilon$ & $\Z+jets$  & $\epsilon$ & $t\bar{t}+jets$  & $\epsilon$ \\ \hline
256 > All events                       & 546   &                    & 72,700 &                     & 1,268,000       &                       & 17,600     &               \\
257 > Found $\Z \to ee$         & 205   & 38\%         & 27,800 & 38\%            & 502,300          & 40\%            & 2,920        & 17\%    \\
258 > Found $\W \to e\nu$    & 42.0  & 21\%         & 171       & 0.6\%           & 309.6               & 0.06\%        & 13.8           & 0.5\%   \\
259 > \W lepton $p_T$ cut    & 34.9  & 83\%          & 23.7     & 14\%            & 86.8                  & 28 \%          &   8.3            & 60\%   \\
260 > Passes HLT                  & 34.7  & 100\%        & 23.6     & 99\%            & 86.8                  &100\%         &   8.3            & 100\%  \\
261 > \Z mass window           & 31.6  & 91\%          & 17.5     & 74\%            & 51.9                  &60\%           &    3.3            & 39\%    \\ \hline
262 > Overall efficiency        &           &  5.8\%        &              &   0.024\%    &                            & 0.0041\%  &                     & 0.019\% \\
263 > \hline\hline
264 >
265 > \multicolumn{9}{c}{ {\bf $2e1\mu$ Channel}} \\ \hline  \hline
266 > Step   & \WZ  & $\epsilon$ & $b\bar{b}\ell\ell$ & $\epsilon$ & $\Z+jets$  & $\epsilon$ & $t\bar{t}+jets$ & $\epsilon$  \\ \hline
267 > All events                        & 546  &             & 72,770 &                 & 1,268,000       &                    & 17,600            &             \\
268 > Found $\Z \to ee$          & 201  & 38\%  & 27,800  & 38\%      &  502,300          &  40\%     &     2,921          &17\% \\
269 > Found $\W \to \mu\nu$ & 47.9 & 23\%  & 748       & 2.7\%      &  2194         &  0.43\%  &      56.8          &1.9\% \\
270 > \W lepton $p_T$ cut      & 37.1 & 77\%  & 9.6        & 1.3\%      &   9.6                  &  0.4\%         &      17.5         &31\% \\
271 > Passes HLT                    & 36.2 & 98\%  & 9.3        & 96\%       &   8.3                  &  87\%    &     15.2   & 87 \%) \\
272 > \Z mass window             & 32.5 & 90\%  & 8.2        &  88\%      &    7.3                 &  88\%            &       4.9         & 32\%) \\ \hline
273 > Overall efficiency          &          & 6.0\% &               & 0.011\% &                           &  0.00058\% &                      &     0.028\% \\
274 > \hline \hline
275 >
276 > \multicolumn{9}{c}{ {\bf $2\mu1e$ Channel}} \\ \hline  \hline
277 > Step   & \WZ   & $\epsilon$ & $b\bar{b}\ell\ell$   & $\epsilon$ & $\Z+jets$   & $\epsilon$ & $t\bar{t}+jets$  & $\epsilon$ \\ \hline
278 > All events       & 546  &   & 72,770   &    & 1,268,000 &    & 17,600 &  \\
279 > Found $\Z \to \mu\mu$     & 234  &43\%&      31,890 & 44\% & 577,200 & 46\%   & 2779 & 16\% \\
280 > Found $\W \to e\nu$          & 48.8 &21\%&    214        & 0.67\%   & 702 & 0.12\%         & 15.1 & 0.54\% \\
281 > \W lepton $p_T$ cut          & 40.7 &83\%&      50.6      & 24\%      & 464.0 & 66\%      & 10.3 & 68\% \\
282 > $\Delta R(e,\mu)$ cut       & 40.6&100\%&      23.3     & 46\%     & 93.0 & 20\%         & 7.1 & 70\%  \\
283 > Passes HLT                       & 39.4 &97\%&        23.2     & 99\%      & 88.8 & 95\%        & 6.6  & 93\%  \\
284 > \Z mass window                & 35.6 & 90\% &          18.9 & 81\%      & 50.3 & 57\%       & 2.8   &44\%  \\ \hline
285 > Overall efficiency              &           &6.5\%  &                  & 0.026\% &           & 0.0040\%  &          & 0.016\% \\
286 > \hline \hline
287 >
288 > \multicolumn{9}{c}{ {\bf $3\mu$ Channel}} \\ \hline  \hline
289 > Step   & \WZ   & $\epsilon$ & ${b\bar{b}\ell\ell}$   & $\epsilon$ & $\Z+jets$   & $\epsilon$ & ${t\bar{t}+jets}$  & $\epsilon$ \\ \hline
290 > All events       & 546 &   & 72,770  &      & 1,268,000  &   & 17,600 &  \\
291 > Found $Z \to \mu\mu$        & 234     & 43\%   & 31,900 & 44\%       & 577,000 & 45\%          & 2779  & 16 \% \\
292 > Found $W \to \mu$             & 58        & 25 \%  & 811      & 2.5\%      & 2521       & 0.44\%       & 35.3   & 1.23 \% \\
293 > W Lepton Pt cut                   & 44.2    & 77 \% & 8.9         & 1.1\%      & 1.8          & 0.07\%        & 1.7     & 4.8 \% \\
294 > Passes HLT                         & 44.0    & 99\%  & 8.9          & 100\%    & 1.8         & 100 \%        & 1.7     & 100 \% \\
295 > Z mass window                   & 40.0    & 91 \%)  & 7.8        & 88\%      & 1.8          & 100 \%        & 1.2     & 69\% \\ \hline
296 > Overall efficiency               &             & 7.3 \% &                & 0.011\% &                & 0.00015\% &            & 0.0065\% \\
297   \hline
298   \end{tabular}
299  
300 < \begin{tabular}{lcccc} \hline
194 < Step   & WZ  & Z+jets  & TTbar+jets  & bbll\\ \hline
195 < All events       & 546   & 1.2679e+06    & 17556.1       & 72770.4 \\
196 < Found $Z \to \mu\mu$     & 326.484 (59.7955 \%)  & 748256 (59.0152 \%)   & 14081.6 (80.2087 \%)  & 43207.1 (59.3746 \%) \\
197 < Z muon isolation                 & 282.27 (86.4575 \%)   & 669556 (89.4822 \%)   & 4201.52 (29.837 \%)   & 37959.1 (87.8538 \%) \\
198 < Z Lepton $eta$ cut       & 282.27 (100 \%)       & 669547 (99.9987 \%)   & 4200.47 (99.975 \%)   & 37959.1 (99.9998 \%) \\
199 < Z Lepton Pt cut                  & 274.249 (97.1584 \%)  & 657267 (98.1659 \%)   & 3626.81 (86.3429 \%)  & 36945.8 (97.3306 \%) \\
200 < Z Lepton IP cut                  & 249.792 (91.0824 \%)  & 603257 (91.7827 \%)   & 3125.35 (86.1737 \%)  & 33937.7 (91.8581 \%) \\
201 < Found $W \to \mu$        & 73.015 (29.2303 \%)   & 7135.7 (1.18286 \%)   & 774.076 (24.7677 \%)  & 4435.51 (13.0696 \%) \\
202 < W Lepton $\eta$ cut      & 72.956 (99.9192 \%)   & 7110.07 (99.6409 \%)  & 774.076 (100 \%)      & 4432.32 (99.9282 \%) \\
203 < W $\mu$ isolation        & 66.724 (91.4578 \%)   & 3382.99 (47.5803 \%)  & 78.3017 (10.1155 \%)  & 1560.97 (35.2178 \%) \\
204 < W muon isolation         & 50.1118 (75.1031 \%)  & 6.25174 (0.184799 \%)         & 5.8096 (7.41951 \%)   & 20.6775 (1.32466 \%) \\
205 < Passes HLT               & 49.7972 (99.3723 \%)  & 6.25174 (100 \%)      & 5.8096 (100 \%)       & 20.6034 (99.6416 \%) \\
206 < Z mass window    & 45.1576 (8.27062 \%)  & 4.9976 (0.000394162 \%)       & 1.683 (0.00958638 \%)         & 18.3059 (0.0251557 \%) \\
207 < \hline
208 < \end{tabular}
300 >
301   \caption{Expected number of signal and background events passing the different
302 <  selections steps in the \WZ, \ttbar and \Zbbbar samples for an integrated luminosity
302 >  selections steps together with the efficiency of each requirement and total efficiency of
303 >  selection criteria in the \WZ, \Zbbbar, \Zjets and \ttjets samples for an integrated luminosity
304    of 1 \invfb.}
305   \label{tab:sel-effA}
306   \end{center}
307   \end{table}
308  
309 + \begin{table}[p]
310 + \begin{center}
311 + \begin{tabular}{l|ccccc}
312 + \hline \hline
313 +   & \multicolumn{5}{c}{$\Z \to ee$ and \W decay modes below} \\
314 + Reconstruction channel  &  $e \nu$
315 +   &  $\mu \nu $
316 +   &  $\tau \nu \to e \nu \nu  $
317 +   &  $\tau \nu \to \mu \nu \nu $
318 +   &  $\tau \nu \to {\rm hadrons~} \nu$
319 + \\ \hline
320 + $3e$       &  17.4 \%  &  0.0319 \%  &  6.42 \%  &  0 \%  &  0.162 \% \\
321 + $2e1\mu$   &  0 \%  &  18.6 \%  &  0 \%  &  5.53 \%  &  0.0485 \% \\
322 + $2\mu1e$   &  0 \%  &  0 \%  &  0 \%  &  0 \%  &  0 \% \\
323 + $3\mu$     &  0 \%  &  0 \%  &  0 \%  &  0 \%  &  0 \% \\
324 + \hline \hline
325 +
326 + & \multicolumn{5}{c}{$\Z \to \mu\mu$ and \W decay modes below} \\
327 + Reconstruction channel  &  $e\nu$
328 +   &  $\mu\nu$
329 +   &  $\tau\nu \to e\nu\nu$
330 +   &  $\tau\nu \to \mu\nu\nu$
331 +   &  $\tau\nu \to {\rm hadrons~}\nu$
332 + \\ \hline
333 + $3e$        &  0 \%  &  0 \%  &  0 \%  &  0 \%  &  0 \% \\
334 + $2e1\mu$   &  0.0104 \%  &  0 \%  &  0 \%  &  0 \%  &  0 \% \\
335 + $2\mu1e$   &  19.6 \%  &  0.0208 \%  &  5.56 \%  &  0 \%  &  0.18 \% \\
336 + $3\mu$     &  0 \%  &  23.4 \%  &  0.0573 \%  &  6.77 \%  &  0.0164 \% \\
337 + \hline \hline
338 + \end{tabular}
339 + \end{center}
340 + \caption{Selection efficiency for signal events in the four selection channels for the different
341 +  generated \W and \Z decay channels.}
342 + \label{tab:wz-effimatrix}
343 +
344 + %\end{table}
345 + %\begin{table}[tbp]
346 + \begin{center}
347 + \begin{tabular}{llcc} \hline
348 +  & & \multicolumn{2}{c}{Generated decay} \\
349 +  & & \multicolumn{2}{c}{$\Z \to ee $} \\
350 + Selection channel  &    &  $\W \to e\nu$   &  $\W \to \mu\nu$ \\
351 + \hline \hline
352 + \multicolumn{4}{c}{all} \\ \hline
353 + $3e$        & all & 1644 events         & 3 events    \\
354 + $3e$        & matched \Z & 93$\pm$1\% & 100\%\\
355 + $3e$        & matched \W & 92$\pm$1\% & 0\\
356 + $3e$        & matched \WZ & 91$\pm$1\% & 0\\
357 + \hline \hline
358 +
359 + \multicolumn{4}{c}{exactly 1 \W lepton candidate} \\ \hline
360 + $3e$        & all & 1602  events       & 0 events    \\
361 + $3e$        & matched \Z & 94$\pm$1\% & 0\\
362 + $3e$        & matched \W & 92$\pm$1\% & 0\\
363 + $3e$        & matched \WZ & 91$\pm$1\% & 0\\
364 + \hline \hline
365 +
366 + \multicolumn{4}{c}{more than 1 \W lepton candidate} \\ \hline
367 + $3e$        & all & 42 events  & 3 events   \\
368 + $3e$        & matched \Z & 93$\pm$4\% & 100\%\\
369 + $3e$        & matched \W & 91 $\pm$5\% & 0\\
370 + $3e$        & matched \WZ & 91$\pm$5\% & 0\\
371 + \hline \hline
372 +
373 + \multicolumn{4}{c}{all} \\ \hline
374 + $2e1\mu$   & all & 0  events   & 1746 events \\
375 + $2e1\mu$   & matched \Z & 0 & 100\%\\
376 + $2e1\mu$   & matched \W & 0 & 100\%\\
377 + $2e1\mu$   & matched \WZ & 0 & 100\%\\
378 + \hline \hline
379 +
380 + \multicolumn{4}{c}{exactly 1 \W lepton candidate} \\ \hline
381 + $2e1\mu$   & all & 0 events    & 1715 events \\
382 + $2e1\mu$   & matched \Z & 0 & 100\%\\
383 + $2e1\mu$   & matched \W & 0 & 100\%\\
384 + $2e1\mu$   & matched \WZ & 0 & 100\%\\
385 + \hline \hline
386 +
387 + \multicolumn{4}{c}{more than 1 \W lepton candidate} \\ \hline
388 + $2e1\mu$   & all & 0     & 31   \\
389 + $2e1\mu$   & matched \Z & 0 & 100\%\\
390 + $2e1\mu$   & matched \W & 0 & 100\%\\
391 + $2e1\mu$   & matched \WZ & 0 & 100\% \\ \hline \hline
392 + \end{tabular}
393 + \end{center}
394 + \caption{Fractions of events with correctly matched leptons
395 +  to true decay product of \W and \Z decays for final states
396 +  with generated $\Z\to ee$ decays}
397 + \label{tab:wz-matcheffi-Zee}
398 + \end{table}
399 +
400  
401  
402 < \subsection{Signal extraction}
402 > \begin{table}[tbp]
403 > \begin{center}
404 > \begin{tabular}{llcc} \hline
405 >  & & \multicolumn{2}{c}{Generated decay:} \\
406 > & & \multicolumn{2}{c}{$\Z \to \mu\mu $} \\
407 > Selection channel  &    &  $\W \to e\nu$   &  $\W \to \mu\nu$
408 > \\
409 > \hline \hline
410 > \multicolumn{4}{c}{all} \\ \hline
411 > $2\mu1e$   & all & 1895 events  & 2 events   \\
412 > $2\mu1e$   & matched \Z & 100\% & 100\%\\
413 > $2\mu1e$   & matched \W & 99$\pm$1\% & 0\\
414 > $2\mu1e$   & matched \WZ & 99$\pm$1\% & 0\\
415 > \hline \hline
416 >
417 > \multicolumn{4}{c}{exactly 1 \W lepton candidate} \\ \hline
418 > $2\mu1e$   & all & 1847 events & 0 events    \\
419 > $2\mu1e$   & matched \Z & 100\% & 0\\
420 > $2\mu1e$   & matched \W & 99$\pm$1\% & 0\\
421 > $2\mu1e$   & matched \WZ & 99$\pm$1\% & 0\\
422 > \hline \hline
423 >
424 > \multicolumn{4}{c}{more than 1 \W lepton candidate} \\ \hline
425 > $2\mu1e$   & all & 48 events   & 2 events    \\
426 > $2\mu1e$   & matched \Z & 100\% & 100\%\\
427 > $2\mu1e$   & matched \W & 94$\pm$3.5\%& 0\\
428 > $2\mu1e$   & matched \WZ & 94$\pm$3.5\% & 0\\
429 > \hline \hline
430 >
431 > \multicolumn{4}{c}{all} \\ \hline
432 > $3\mu$     & all & 0 events   & 2251 events \\
433 > $3\mu$     & matched \Z & 0 & 94$\pm$1\%\\
434 > $3\mu$     & matched \W & 0 & 93$\pm$1\%\\
435 > $3\mu$     & matched \WZ & 0 & 93$\pm$1\%\\
436 > \hline \hline
437 >
438 > \multicolumn{4}{c}{exactly 1 \W lepton candidate} \\ \hline
439 > $3\mu$     & all & 0 events    & 2207 events \\
440 > $3\mu$     & matched \Z & 0 & 94$\pm$1\%\\
441 > $3\mu$     & matched \W & 0 & 93$\pm$1\%\\
442 > $3\mu$     & matched \WZ & 0 & 93$\pm$1\%\\
443 > \hline \hline
444 >
445 > \multicolumn{4}{c}{more than 1 \W lepton candidate} \\ \hline
446 > $3\mu$     & all & 0 events    & 44 events  \\
447 > $3\mu$     & matched \Z & 0 & 91$\pm$4\%\\
448 > $3\mu$     & matched \W & 0 & 91$\pm$4\%\\
449 > $3\mu$     & matched \WZ & 0 & 91$\pm$4\%\\ \hline \hline
450 > \end{tabular}
451 > \end{center}
452 > \caption{Fractions of MC \WZ events with correctly matched leptons
453 >  to true decay product of \W and \Z decays for final states
454 >  with generated $\Z\to \mu\mu$ decays}
455 > \label{tab:wz-matcheffi-Zmumu}
456 > \end{table}
457  
458 < \input D0Matrix
458 >
459 > %\subsection{Signal extraction}
460 > %\input D0Matrix
461   \input zjetbackground
462  
463  
464 < \subsection{Systematic uncertainties}
464 > \section{Systematic uncertainties}
465   \input Sys
466  
467  
468   \begin{figure}[bt]
469    \begin{center}
470 +  \scalebox{0.8}{\includegraphics{figs/met_by_channel.eps}}
471 +  \caption{Missing transverse mass for the four signal categories.
472 +    The distributions  show the number of expected events
473 +    for $1 fb^{-1}$. Only events with 81.1 GeV $< M_Z < $ 101.1 \gev
474 +    are shown. All selection cuts are applied.}
475 +  \label{fig:met}
476 +  \end{center}
477 + \end{figure}
478 +
479 + \begin{figure}[bt]
480 +  \begin{center}
481    \scalebox{0.8}{\includegraphics{figs/mtw_by_channel.eps}}
482    \caption{W transverse mass for the four signal categories.
483      The distributions  show the number of expected events
484 <    for $1 fb^{-1}$. Only events with 81.1 GeV $< M_Z < $ 101.1 GeV are shown.}
484 >    for $1 fb^{-1}$. Only events with 81.1 GeV $< M_Z < $ 101.1 GeV are shown.
485 >    All selection cuts are applied.}
486    \label{fig:mtw}
487    \end{center}
488   \end{figure}
489 +
490 +
491 +
492 +
493 +

Diff Legend

Removed lines
+ Added lines
< Changed lines
> Changed lines