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\section{Introduction}
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\label{sec:intro}
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Supersymmetry (SUSY) is a popular extension to the standard model (SM) of particle physics, which may explain
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the 16 orders of magnitude difference between the electroweak and Planck scales (hierarchy problem), introduce
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a natural candidate for the dark matter weakly-interacting massive particle (WIMP), and lead to the unification of
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gauge couplings.
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In order to solve the hierarchy problem without fine-tuning, SUSY must introduce
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light top and bottom squarks, the SUSY partners of the top and bottom quarks~\cite{ref:naturalsusy}.
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If R-parity is conserved, the lightest SUSY particle (LSP),
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usually the lightest neutralino \lsp, is a stable WIMP. If produced in pp collisions this
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particle carries away undetected energy and leads to large missing transverse energy (\met).
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In this note we present the results of searches for top and bottom squarks in final states with \met,
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using data collected by the Compact Muon Solenoid (CMS)~\cite{ref:CMS} detector at the
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Large Hadron Collider (LHC). The data was collected at a center-of-mass energy $\sqrt{s}=8$~TeV in 2012
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and corresponds to an integrated luminosity of approximately 10~fb$^{-1}$.
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\begin{figure*}
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\begin{center}
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\subfloat[] {
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\includegraphics[width=0.35\textwidth]{HCPPlots/T2tt.pdf}
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}\quad
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\subfloat[] {
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\includegraphics[width=0.35\textwidth]{HCPPlots/T2bw.pdf}
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}\quad
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\subfloat[] {
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\includegraphics[width=0.35\textwidth]{HCPPlots/T2bb.pdf}
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}
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\subfloat[] {
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\includegraphics[width=0.35\textwidth]{HCPPlots/T2ttww.pdf}
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}
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\caption{Example topologies with direct pair production of top (a,b) and bottom (c,d) squarks.
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\label{fig:diagrams}
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}
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\end{center}
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\end{figure*}
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%\begin{figure*}
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%\centering
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%\includegraphics[width=1cm,clip]{HCPPlots/T2tt.pdf}
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%% Use the relevant command for your figure-insertion program
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%% to insert the figure file. See example above.
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%% If not, use
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%\vspace*{5cm} % Give the correct figure height in cm
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%\caption{Please write your figure caption here}
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%\label{fig:diagrams} % Give a unique label
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%\end{figure*}
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Top and bottom squarks may either be produced directly in pairs
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(direct squark pair production) or in the decays of heavier SUSY particles such as the gluino (gluino-mediated squark production).
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In this note we focus on searches for direct squark pair production; examples of such processes are indicated in Fig.~\ref{fig:diagrams}.
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These scenarios may lead to excesses above the SM background expectations in several final states,
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depending on the mass hierarchy of the SUSY particles.
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Here we report the results from three searches which focus on the single lepton final state using the transverse
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mass~\cite{ref:stop}, the same-sign dilepton final state~\cite{ref:ss}, and the all-hadronic final state using the \alphat\ quantity~\cite{ref:alphat}.
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