22 |
|
These three predictions are in good agreement with each other |
23 |
|
and with the observation of one event in the signal region. |
24 |
|
We calculate a Bayesian 95\% CL upper limit\cite{ref:bayes.f} |
25 |
< |
on the number of non SM events in the signal region to be X. |
26 |
< |
This was calculated using a background prediction of $N_{BG}=X \pm Y$ |
27 |
< |
{\bf \color{red} WHAT TO TAKE FOR $N_{BG}$???.} |
25 |
> |
on the number of non SM events in the signal region to be 4.1. |
26 |
> |
We have also calculated this limit using a profile likelihood method |
27 |
> |
as implemented in the cl95cms software, and we also find 4.1. |
28 |
> |
These limits were calculated using a background prediction of $N_{BG}=1.7 \pm 1.1$ |
29 |
|
events. The upper limit is not very sensitive to the choice of |
30 |
|
$N_{BG}$ and its uncertainty. |
31 |
|
|
32 |
|
To get a feeling for the sensitivity of this search to some |
33 |
|
popular SUSY models, we remind the reader of the number of expected |
34 |
|
LM0 and LM1 events from Table~\ref{tab:sigcont}: $6.3 \pm 1.3$ |
35 |
< |
events and $2.6 \pm 0.4$ ({\bf \color{red} Update uncertainties}) |
35 |
> |
events and $2.6 \pm 0.4$ |
36 |
|
respectively, where the uncertainties |
37 |
|
are from energy scale (Section~\ref{sec:systematics}), luminosity, |
38 |
|
and lepton efficiency. Note that these expected SUSY yields |
43 |
|
in this note is a difficult issue. The next paragraph represent |
44 |
|
our attempt at doing so. |
45 |
|
|
45 |
– |
{\bf \color{red} Some of these results may need to be updated with 38X systematic studies} |
46 |
|
Other models of new physics in the dilepton final state |
47 |
|
can be confronted in an approximate way by simple |
48 |
|
generator-level studies that |
50 |
|
with our upper limit of 4.1 events. The key ingredients |
51 |
|
of such studies are the kinematical cuts described |
52 |
|
in this note, the lepton efficiencies, and the detector |
53 |
< |
responses for SumJetPt and \met/$\sqrt{\rm SumJetPt}$. |
53 |
> |
responses for SumJetPt and \met/$\sqrt{\rm SumJetPt}$. These |
54 |
> |
quantities have been evaluated with Spring10 MC samples, |
55 |
> |
and we are currently checking if any of them change after |
56 |
> |
switching to Fall10 MC. |
57 |
|
The muon identification efficiency is $\approx 95\%$; |
58 |
|
the electron identification efficiency varies from $\approx$ 63\% at |
59 |
|
$P_T = 10$ GeV to 91\% for $P_T > 30$ GeV. The isolation |
60 |
|
efficiency in top events varies from $\approx 83\%$ (muons) |
61 |
|
and $\approx 89\%$ (electrons) at $P_T=10$ GeV to |
62 |
< |
$\approx 95\%$ for $P_T>60$ GeV. The average detector |
62 |
> |
$\approx 95\%$ for $P_T>60$ GeV. |
63 |
> |
{\bf \color{red} THE FOLLOWING QUANTITIES SHOULD BE RECALCULATED AFTER |
64 |
> |
WE FIX THE BUGS WITH THE MET IN LM SAMPLES} |
65 |
> |
The average detector |
66 |
|
responses for SumJetPt and $\met/\sqrt{\rm SumJetPt}$ are |
67 |
|
$1.00 \pm 0.05$ and $0.94 \pm 0.05$ respectively, where |
68 |
|
the uncertainties are from the jet energy scale uncertainty. |
77 |
|
signal region. |
78 |
|
% (SumJetPt $>$ 300 GeV and \met/$\sqrt{\rm SumJetPt} > 8.5$ |
79 |
|
% Gev$^{\frac{1}{2}}$). |
80 |
+ |
{\bf \color{red} THE FOLLOWING QUANTITIES SHOULD BE RECALCULATED AFTER |
81 |
+ |
WE FIX THE BUGS WITH THE MET IN LM SAMPLES} |
82 |
|
We find that the average SumJetPt response |
83 |
|
in the Monte Carlo |
84 |
|
is very close to one, with an RMS of order 10\% while |
106 |
|
The response is defined as the ratio of the reconstructed quantity |
107 |
|
to the true quantity in MC. These plots are done using the LM0 |
108 |
|
Monte Carlo, but they are not expected to depend strongly on |
109 |
< |
the underlying physics.} |
109 |
> |
the underlying physics. |
110 |
> |
{\bf \color{red} UPDATE AFTER FIXING BUGS WITH LM SAMPLES. } } |
111 |
|
\end{center} |
112 |
|
\end{figure} |