KK-parity non-conservation in UED confronts LHC data

Abstract

Kaluza-Klein (KK) parity can be violated in five-dimensional universal extra dimensional model with boundary-localized (kinetic or mass) terms (BLTs) at the fixed points of $S^1/Z_2$ orbifold. In this framework we study the resonant production of Kaluza-Klein excitations of the neutral electroweak gauge bosons at the LHC and their decay into an electron-positron pair or a muon-antimuon pair. We use the results (first time in our knowledge) given by the LHC experiment to constrain the mass range of the first KK-excitation of the electroweak gauge bosons ($B^1\ \textrm{and} \ W_3^1$). It is interesting to note that the LHC result puts an upper limit on the masses of the $n=1$ KK-leptons for positive values of BLT parameters and depending upon the mass of $\ell^{+}\ell^{-}$ resonance.