Expected performance of the ATLAS detector in GMSB models with tau final states

Gauge Mediated Supersymmetry Breaking (GMSB) models provide a possible mechanism to mediate supersymmetry to the visible sector. In these models the lightest supersymmetric particle is usually the gravitino, while the next-to-lightest supersymmetric particle (NLSP) is either a neutralino or a slepton. In the case of a $\widetilde{\tau}$ NLSP, events with large missing transverse energy, highly energetic jets and up to four tau leptons are expected in $pp$-collisions at the LHC providing a powerful channel to probe the GMSB theory. In this note we study the expected performance of the ATLAS detector in GMSB scenarios with a $\widetilde{\tau}$ NLSP for a LHC center-of-mass energy of $\sqrt{s}=10\,\mathrm{TeV}$. A cut-based selection is optimised using an example GMSB signal and a scan of the GMSB parameter space is performed to determine the discovery reach as a function of the integrated luminosity. In addition, the invariant mass distribution of two tau leptons is used to study the measurement of masses of supersymmetric particles with larger event samples.