Search for New Physics using the $\alpha_{\mathrm{T}}$ variable in multijet events using b-tagging

We present a search for new physics in $34.6~\mathrm{pb}^{-1}$ of $pp$ collisions at $\sqrt{s}=7$~TeV in the all hadronic mode with the signature of large transverse momentum imbalance and one or more b-quark jets. This momentum imbalance is described by the kinematic variable $\alpha_{\mathrm{T}}$, which substantially reduces the QCD background. Using data driven background estimation methods, we predict $2.34\pm 0.54$ and observe 1 event. We set $95\%$ confidence level upper limits on benchmark Supersymmetry signal models.