Measuring the SUSY Breaking Scale at the LHC in the Slepton NLSP   Scenario of GMSB Models
  We report a study on the measurement of the SUSY breaking scale sqrt(F) in the framework of gauge-mediated supersymmetry breaking (GMSB) models at the LHC. The work is focused on the GMSB scenario where a stau is the next-to-lightest SUSY particle (NLSP) and decays into a gravitino with lifetime c*tau_NLSP in the range 0.5 m to 1 km. We study the identification of long-lived sleptons using the momentum and time of flight measurements in the muon chambers of the ATLAS experiment. A realistic evaluation of the statistical and systematic uncertainties on the measurement of the slepton mass and lifetime is performed, based on a detailed simulation of the detector response. Accessible range and precision on sqrt(F) achievable with a counting method are assessed. Many features of our analysis can be extended to the study of different theoretical frameworks with similar signatures at the LHC. 
S. Ambrosanio (1), B. Mele (2,3), S. Petrarca (3,2), G. Polesello (4),   A. Rimoldi (1,5) ((1) CERN, (2) INFN Roma I, (3) U....