Characteristics of graviton-induced bremsstrahlung

Abstract

We discuss Bremsstrahlung induced by graviton exchange in proton-proton interactions at hadronic colliders, resulting from gg\to G\to \mu^+\mu^-\gamma. Both the ADD and RS scenarios are discussed. Due to the coupling of the graviton to two photons, the cross section has a new kinematical singularity for hard photons. Thus, graviton-induced Bremsstrahlung tends to yield more hard photons than QED-based Bremsstrahlung. As compared with the corresponding two-body final state, \mu^+\mu^-, the cross section is, for realistic cuts, smaller by a factor \sim 0.02. At the LHC, and with a string scale of a few TeV (ADD scenario), or a graviton mass of a few TeV (RS scenario), a few events of high invariant mass are expected per year.