| 12 |
|
the jet energy scale (30\%, see Section~\ref{sec:systematics}), |
| 13 |
|
the luminosity (10\%), and the lepton/trigger |
| 14 |
|
efficiency (10\%)\footnote{Other uncertainties associated with |
| 15 |
< |
the modeling of $t\bar{t}$ in MadGraph have not been evaluated.}. |
| 15 |
> |
the modeling of $t\bar{t}$ in MadGraph have not been evaluated. |
| 16 |
> |
The uncertainty on $pp \to \sigma(t\bar{t})$ is also not included.}. |
| 17 |
|
The data driven background predictions from the ABCD method |
| 18 |
|
and the $P_T(\ell\ell)$ method are 1.5 $\pm$ 0.9 and |
| 19 |
< |
$1.8^{+2.5}_{-1.8}$ events respectively. |
| 19 |
> |
$2.5 \pm 2.2$ events, respectively. |
| 20 |
|
|
| 21 |
|
These three predictions are in good agreement with each other |
| 22 |
|
and with the observation of one event in the signal region. |
| 23 |
< |
We calculate a baysean 95\% CL upper limit\cite{ref:bayes.f} |
| 23 |
> |
We calculate a Bayesian 95\% CL upper limit\cite{ref:bayes.f} |
| 24 |
|
on the number of non SM events in the signal region to be 4.1. |
| 25 |
< |
This was calculated using a background prediction of $N_{BG}=1.4 \pm 1.0$ |
| 25 |
> |
This was calculated using a background prediction of $N_{BG}=1.4 \pm 1.1$ |
| 26 |
|
events. The upper limit is not very sensitive to the choice of |
| 27 |
|
$N_{BG}$ and its uncertainty. |
| 28 |
|
|
| 29 |
|
To get a feeling for the sensitivity of this search to some |
| 30 |
|
popular SUSY models, we remind the reader of the number of expected |
| 31 |
< |
LM0 and LM1 events from Table~\ref{tab:sigcontABCD}: $5.6 \pm 1.1$ |
| 32 |
< |
events and $2.2 \pm 0.3$ respectively, where the uncertainties |
| 31 |
> |
LM0 and LM1 events from Table~\ref{tab:sigcont}: $6.5 \pm 1.3$ |
| 32 |
> |
events and $2.6 \pm 0.4$ respectively, where the uncertainties |
| 33 |
|
are from energy scale (Section~\ref{sec:systematics}), luminosity, |
| 34 |
|
and lepton efficiency. |
| 35 |
|
|
| 36 |
< |
In Figures XX and YY we provide the response functions for the |
| 37 |
< |
SumJetPt and \met/$\sqrt{\rm SumJetPt}$ cuts used in our analysis, |
| 38 |
< |
{\em i.e.} the efficiencies of the experimental cuts as a function of |
| 39 |
< |
the true quantities. Using this information as well as the kinematical |
| 36 |
> |
In Figure~\ref{fig:response} we provide the response functions for the |
| 37 |
> |
SumJetPt and \met/$\sqrt{\rm SumJetPt}$ in MC, as well as the |
| 38 |
> |
efficiency for the cuts on these quantities used in defining the |
| 39 |
> |
signal region. |
| 40 |
> |
% (SumJetPt $>$ 300 GeV and \met/$\sqrt{\rm SumJetPt} > 8.5$ |
| 41 |
> |
% Gev$^{\frac{1}{2}}$). |
| 42 |
> |
We find that the average SumJetPt response |
| 43 |
> |
in the Monte Carlo |
| 44 |
> |
is very close to one, with an RMS of order 10\%; |
| 45 |
> |
the |
| 46 |
> |
response of \met/$\sqrt{\rm SumJetPt}$ is approximately 0.94 with an |
| 47 |
> |
RMS of 14\%. |
| 48 |
> |
|
| 49 |
> |
Using this information as well as the kinematical |
| 50 |
|
cuts described in Section~\ref{sec:eventSel} and the lepton efficiencies |
| 51 |
|
of Figures~\ref{fig:effttbar}, one should be able to confront |
| 52 |
|
any existing or future model via a relatively simple generator |
| 53 |
|
level study by comparing the expected number of events in 35 pb$^{-1}$ |
| 54 |
< |
with our upper limit of 4.1 events. |
| 54 |
> |
with our upper limit of 4.1 events. |
| 55 |
> |
|
| 56 |
> |
\begin{figure}[tbh] |
| 57 |
> |
\begin{center} |
| 58 |
> |
\includegraphics[width=\linewidth]{selectionEff.png} |
| 59 |
> |
\caption{\label{fig:response} Left plots: the efficiencies |
| 60 |
> |
as a function of the true quantities for the SumJetPt (top) and |
| 61 |
> |
tcMET/$\sqrt{\rm SumJetPt}$ (bottom) requirements for the signal |
| 62 |
> |
region as a function of their true values. The value of the |
| 63 |
> |
cuts is indicated by the vertical line. |
| 64 |
> |
Right plots: The average response and its RMS for the SumJetPt |
| 65 |
> |
(top) and tcMET/$\sqrt{\rm SumJetPt}$ (bottom) measurements. |
| 66 |
> |
The response is defined as the ratio of the reconstructed quantity |
| 67 |
> |
to the true quantity in MC. These plots are done using the LM0 |
| 68 |
> |
Monte Carlo, but they are not expected to depend strongly on |
| 69 |
> |
the underlying physics.} |
| 70 |
> |
\end{center} |
| 71 |
> |
\end{figure} |
