Measurements of masses in supergravity models at CERN LHC

This paper presents new measurements in a case study of the minimal supergravity (SUGRA) model with m₀=100GeV, m1/2=300GeV, A₀=0, tanβ=2, and sgnμ=+ based on four-body distributions from three-step decays and on minimum masses in such decays. These measurements allow masses of supersymmetric particles to be determined without relying on a model. The feasibility of testing slepton universality at the {~}0.1% level at high luminosity is discussed. In addition, the effect of enlarging the parameter space of the minimal SUGRA model is discussed. The direct production of left-handed sleptons and the nonobservation of additional structure in the dilepton invariant mass distributions are shown to provide additional constraints.