| 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} |
| 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 |
+ |
\clearpage |
