Analysis of the long-lived slepton next-to-lightest supersymmetric particle in the gauge-mediated supersymmetry breaking model at a linear collider -art. no. 015005

We performed an analysis on the detection of a long-lived slepton at a line ar collider with roots = 500 GeV. In gauge-mediated symmetry breaking model s a long-lived NLSP is predicted for a large value of the supersymmetry bre aking scale rootF. Furthermore in a large portion of the parameter space th is particle is a stau. Such heavy charged particles will leave a track in t he tracking volume and hit the muonic detector. In order to disentangle thi s signal from the muon background, we explore the kinematics and particle i dentification tools: a time-of-flight device, dE/dX, and Cherenkov devices. We show that a linear collider will be able to detect long-lived staus wit h masses up to the kinematical limit of the machine. We also present our es timation of the sensitivity to the stau lifetime.