Indirect Searches for Z′Z'-like Resonances at the LHC

We explore the possibility of indirectly observing the effects of $Z'$-like particles with electroweak strength couplings in the Drell-Yan channel at the LHC with masses above the resonance direct search reach. We find that, mostly due to statistical limitations, this is very unlikely in almost all classes of models independently of the spin of the resonance. Not unexpectedly, the one possible exception to this general result is the case of degenerate Kaluza-Klein (KK) excitations of the photon and $Z$ that occur in some extra-dimensional models. In this special case, the strong destructive interference with the Standard Model (SM) exchanges below the resonance mass leads to a well-known significant suppression of the cross section and thus increased sensitivity to this particular new physics scenario.Comment: 18 pages, 6 figs, discussion and reference adde