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\section{Introduction} |
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In this note we describe a search for new physics in the 2010 |
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In this note we describe a search for new physics in the 2011 |
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opposite sign isolated dilepton sample ($ee$, $e\mu$, and $\mu\mu$). |
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The main sources of high \pt isolated dileptons at CMS are Drell Yan and $t\bar{t}$. |
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The main sources of high \pt isolated dileptons at CMS are Drell Yan and \ttbar. |
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Here we concentrate on dileptons with invariant mass consistent |
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with $Z \to ee$ and $Z \to \mu\mu$. A separate search for new physics in the non-\Z |
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sample is described in~\cite{ref:GenericOS}. |
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We search for new physics in the final state of \Z plus two or more jets plus missing transverse energy (MET). We reconstruct the \Z boson |
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in its decay to $e^+e^-$ or $\mu^+\mu^-$. Our search regions are defined as MET $\ge$ 60~GeV (loose signal region) and MET $\ge$ 120~GeV (tight signal region), and two or more jets. We use data driven techniques to predict the |
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in its decay to $e^+e^-$ or $\mu^+\mu^-$. Our search regions are defined as MET $\ge$ \signalmetl~GeV (loose signal region) and MET $\ge$ \signalmett~GeV (tight signal region), and two or more jets. We use data driven techniques to predict the |
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standard model background in this search region. |
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Contributions from Drell-Yan production combined with detector mis-measurements that produce fake MET are modeled via MET templates based on photon plus jets events. |
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Top pair production backgrounds, as well as other backgrounds for which the lepton |
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flavors are uncorrelated such as $VV$ and DY$\rightarrow\tau\tau$, are modeled via $e^\pm\mu^\mp$ subtraction. |
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flavors are uncorrelated such as di-bosons ($VV$) and DY$\rightarrow\tau\tau$, are modeled via $e^\pm\mu^\mp$ subtraction. |
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As leptonically decaying \Z bosons is a signature that has very little background, they provide a clean final state in which to search for new physics. |
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Because new physics is expected to be connected to the Standard Model Electroweak sector, it is likely that new particles will couple to W and Z bosons. |
