Sensitivity to Contact Interactions and Extra Dimensions in Di-lepton and Di-photon Channels at Future Colliders

Virtual effects from a generic description of physics beyond the Standard Model in terms of contact interactions, or from large extra dimensions will modify the observed cross sections for easy to detect final states like lepton or photon pairs, and can be used to probe scales much higher than the center-of-mass energy of the partons initiating the interactions. In this note the sensitivity reach of the Large Hadron Collider to contact interactions in the Drell-Yan channels and of a Future Linear Collider to contact interactions and extra dimensions in $e^+e^-$, $\mu^+\mu^-$ and $\gamma\gamma$ final states are studied. Experimental aspects of the measurements, systematic error effects and the evolution of the search reach with accumulated luminosity are considered.