Search for Contact Interactions in the Dimuon Channel in p-p Interactions at $\sqrt{s}=$ 7 TeV

Quark and muon sub-structure is manifest as a deviation from the Standard Model prediction for the invariant mass distribution of opposite-sign dimuon pairs. A search strategy is presented based on a left-handed current model of Contact Interactions. Expected limits are shown as a function of minimum invariant mass. The measured mass distribution is reported based on a data sample corresponding to 5 fb$^{-1}$.