| 22 |
|
with one real lepton and one fake lepton are estimated by |
| 23 |
|
selecting one lepton passing the full lepton selection |
| 24 |
|
and one failing it but passing the FO selection. |
| 25 |
< |
Backgrounds with two fake leptons are estimated by requiring |
| 25 |
> |
Backgrounds with two fake leptons (QCD) are estimated by requiring |
| 26 |
|
both lepton candidates to pass the FO selection and fail |
| 27 |
|
the full selection. |
| 28 |
< |
\item Each event is weighted by FR/(1-FR), where FR is the Fake |
| 29 |
< |
Rate for the FO in the event. In case of two FO, we take the |
| 30 |
< |
weight as the product of the two FR/(1-FR) for the two FO. |
| 28 |
> |
\item For the QCD backgrounds considered in this note, |
| 29 |
> |
each event is weighted by the product of the two factors |
| 30 |
> |
of FR/(1-FR), where FR is the Fake |
| 31 |
> |
Rate for each of the two FO. |
| 32 |
|
\item The sum of the weights over the selected events is the |
| 33 |
|
background prediction. |
| 34 |
|
\end{itemize} |
| 111 |
|
be estimated. |
| 112 |
|
|
| 113 |
|
The FR are measured as a function of $P_T$ and $|\eta|$. |
| 114 |
< |
The FR projections on the $P_T$ axis for the muon FR and for |
| 114 |
> |
The FR projections on the $P_T$ and $|\eta|$ axes for the muon FR and for |
| 115 |
|
the three (V1, V2, V3) electron FR in the different trigger samples |
| 116 |
|
are displayed in Figures~\ref{fig:muFR} and~\ref{fig:eleFR}. |
| 117 |
|
|
| 118 |
|
|
| 119 |
|
\begin{figure}[htb] |
| 120 |
|
\begin{center} |
| 121 |
< |
\includegraphics[width=0.7\linewidth]{MuFakeRatesJune1.pdf} |
| 121 |
> |
\includegraphics[width=0.48\linewidth]{MuFakeRatesJune1.pdf} |
| 122 |
> |
\includegraphics[width=0.48\linewidth]{muFReta.pdf} |
| 123 |
|
\caption{\label{fig:muFR}The muon fake rate as a function of $P_T$ |
| 124 |
< |
in the different jet samples.} |
| 124 |
> |
and $|\eta|$ in the different jet samples.} |
| 125 |
|
\end{center} |
| 126 |
|
\end{figure} |
| 127 |
|
|
| 128 |
|
\begin{figure}[htb] |
| 129 |
|
\begin{center} |
| 130 |
|
\includegraphics[width=\linewidth]{ElFakeRatesJune1.pdf} |
| 131 |
+ |
\includegraphics[width=\linewidth]{eFReta.pdf} |
| 132 |
|
\caption{\label{fig:eleFR}The electron fake rates |
| 133 |
< |
(V1,V2,V3) as a function of $P_T$ in the different jet samples.} |
| 133 |
> |
(V1,V2,V3) as a function of $P_T$ and $|\eta|$ |
| 134 |
> |
in the different jet samples.} |
| 135 |
|
\end{center} |
| 136 |
|
\end{figure} |
| 137 |
|
|
| 149 |
|
as we collect more data. In any case, the |
| 150 |
|
FR does not appear to change very fast as a function of $P_T$. |
| 151 |
|
|
| 152 |
+ |
|
| 153 |
+ |
\subsection{Loosening the isolation requirement for the muon FO} |
| 154 |
+ |
Loosening the isolation requirement for the muon FO would reduce the |
| 155 |
+ |
muon FR. This is in general ``a good thing''\texttrademark. |
| 156 |
+ |
However, the price one then pays is that the jet dependence of the |
| 157 |
+ |
FR increases. This is illustrated in Figure~\ref{fig:FRlooseIso}. |
| 158 |
+ |
|
| 159 |
+ |
In the $P_T \approx 8$ GeV bin, the ratio of FR in the two extreme triggers |
| 160 |
+ |
(HLT\_L1Jet6U and HLT\_Jet30U) increases from 1.6 (FO-Iso $<$ 0.4) to 2.0 |
| 161 |
+ |
(FO-Iso $<$ 0.6) to 2.4 (FO-Iso $<$ 0.8) to 2.9 (FO-Iso $<$ 1.0). Given this |
| 162 |
+ |
behavior, for now we keep the FO isolation requirement to 0.4. |
| 163 |
+ |
|
| 164 |
+ |
\begin{figure}[htb] |
| 165 |
+ |
\begin{center} |
| 166 |
+ |
\includegraphics[width=0.7\linewidth,angle=90]{muonFR_differentIso.pdf} |
| 167 |
+ |
\caption{\label{fig:FRlooseIso}Muon FR as a function of $P_T$ in different |
| 168 |
+ |
trigger samples for different choices of the maximum isolation |
| 169 |
+ |
requirement on the muon FO (0.4, 0.6, 0.8, 1.0).} |
| 170 |
+ |
\end{center} |
| 171 |
+ |
\end{figure} |
| 172 |
+ |
|
| 173 |
+ |
|
| 174 |
|
\subsection{Bias due to lepton triggers?} |
| 175 |
|
Another possible bias is related to the fact that events used to |
| 176 |
|
measure the FR are collected with jet triggers. On the other hand |
| 214 |
|
The statistics are not very good, but the lepton trigger bias |
| 215 |
|
does not seem to be a significant effect. We tentatively neglect it. |
| 216 |
|
|
| 217 |
< |
\subsection{Test in $\gamma +$ jet} |
| 192 |
< |
|
| 193 |
< |
\noindent{\bf This Section is a placeholder for a study that has |
| 194 |
< |
no been done yet. We may just comment it out before releasing |
| 195 |
< |
the note on Monday} |
| 196 |
< |
|
| 197 |
< |
Next, we want to test the FR measured in jet triggered data on |
| 198 |
< |
a $\gamma +$ jet sample. This is an interesting test because |
| 199 |
< |
the jets in $\gamma +$ jets have a different heavy flavor and |
| 200 |
< |
quark-to-gluon ration than the jets in typical QCD events. |
| 201 |
< |
|
| 202 |
< |
To perform this test we select a $\gamma + jets$ sample in the |
| 203 |
< |
following way: |
| 204 |
< |
|
| 205 |
< |
\begin{itemize} |
| 206 |
< |
|
| 207 |
< |
\item We use the EG Secondary/Primary dataset. |
| 208 |
< |
\item We require that the Photon\_10\_L1R trigger fired. |
| 209 |
< |
\item We selet offline photons as...... |
| 210 |
< |
\item We match the offline-selected photon with the HLT object |
| 211 |
< |
that fired the Photon10\_10\_L1R trigger. |
| 212 |
< |
\item If there are two such offline photons passing the cuts, |
| 213 |
< |
we reject the event (for simplicity? Not sure...). |
| 214 |
< |
\item We also need to reject $z \to ee$ somehow |
| 215 |
< |
\item We select FO that fail the cuts of Sections~\ref{sec:eleID} |
| 216 |
< |
and~\ref{sec:muID}. We weight each of these events by FR/(1-FR). |
| 217 |
< |
\item We then select leptons that pass the cuts of Sections~\ref{sec:eleID} |
| 218 |
< |
and~\ref{sec:muID}. We compare the yield of these events with the |
| 219 |
< |
FR background prediction which is the sum of the weighted events above. |
| 220 |
< |
|
| 221 |
< |
\end{itemize} |
| 222 |
< |
|
| 223 |
< |
The reslts are shown in Table~\ref{tab:gammajet}. |
| 224 |
< |
|
| 225 |
< |
\begin{table}[htb] |
| 226 |
< |
\begin{center} |
| 227 |
< |
\caption{\label{tab:gammajet} Observed and predicted yields of leptons |
| 228 |
< |
in the $\gamma +$ jet sample.} |
| 229 |
< |
\begin{tabular}{|l|c|c|c|c|c||} \hline |
| 230 |
< |
& Observed & V1 predicted & V2 predicted & V3 predicted & Muon Predicted \\ |
| 231 |
< |
\hline |
| 232 |
< |
electrons & & & & & n.a. \\ |
| 233 |
< |
muons & & n.a. & n.a. & n.a. & \\ |
| 234 |
< |
\hline |
| 235 |
< |
\end{tabular} |
| 236 |
< |
\end{center} |
| 237 |
< |
\end{table} |
| 238 |
< |
|
| 239 |
< |
{\em Here we comment on what we see.} |
| 217 |
> |
\clearpage |
