Sensitivity to Contact Interactions from Quark Compositeness at CMS

CMS will measure dijets in proton-proton collisions at $\sqrt{s} =14$ TeV. The angular distribution of dijets as a function of invariant mass is sensitive to a contact interaction among quarks that could arise if quarks are not pointlike particles. The sensitive part of the angular distribution is measured by the dijet ratio: the number of dijet events with $|\eta|<0.5$ divided by the number of dijet events with $0.5<|\eta|<1.0$. As a function of dijet invariant mass, we present estimates of the dijet ratio for both the QCD background and a contact interaction signal. For integrated luminosities of 100 pb$^{-1}$, 1 fb$^{-1}$ and 10 fb$^{-1}$, we present CMS capability to exclude or discover contact interactions from quark compositeness.