Implications of gauge kinetic mixing onZ′and slepton production at the LHC

Abstract

We consider a supersymmetric version of the standard model extended by an additional $U(1{)}_{B\ensuremath{-}L}$. This model can be embedded in an mSUGRA-inspired model where the mass parameters of the scalars and gauginos unify at the scale of grand unification. In this class of models the renormalization group equation evolution of gauge couplings as well as of the soft SUSY-breaking parameters require the proper treatment of gauge kinetic mixing. We first show that this has a profound impact on the phenomenolgy of the ${Z}^{\ensuremath{'}}$ and as a consequence the current LHC bounds on its mass are reduced significantly from about 1970 GeV to 1790 GeV. They are even further reduced if the ${Z}^{\ensuremath{'}}$ can decay into supersymmetric particles. Secondly, we show that in this way sleptons can be produced at the LHC in the 14 TeV phase with masses of several hundred GeV. In the case of squark and gluino masses in the multi-TeV range, this might become an important discovery channel for sleptons up to 800 GeV (900 GeV) for an integrated luminosity of $100\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ ($300\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$).