Discovery and measurement of sleptons, binos, and winos with aZ′

Extensions of the MSSM could significantly alter its phenomenology at theLHC. We study the case in which the MSSM is extended by an additional U(1)gauge symmetry, which is spontaneously broken at a few TeV. The productioncross-section of sleptons is enhanced over that of the MSSM by the process$pp\to Z' \to \tilde{\ell} \tilde{\ell}^*$, so the discovery potential forsleptons is greatly increased. The flavor and charge information in theresulting decay, $\tilde{\ell} \to \ell + {LSP}$, provides a useful handle onthe identity of the LSP. With the help of the additional kinematical constraintof an on-shell Z', we implement a novel method to measure all of thesuperpartner masses involved in this channel. For certain final states with twoinvisible particles, one can construct kinematic observables bounded above byparent particle masses. We demonstrate how output from one such observable,m_T2, can become input to a second, increasing the number of measurements onecan make with a single decay chain. The method presented here represents a newclass of observables which could have a much wider range of applicability.Comment: 20 pages, 15 figures; v2 references added and minor change