  The tau lepton's supersymmetric partner, the stau, appears in some models as
the next-to-lightest supersymmetric particle. Their decay process into the
lightest superpartner is usually suppressed by supersymmetry breaking, which
makes it a long-lived particle. In this scenario, its signature is a long,
minimally ionizing track when traveling through the IceCube detector.
Independent of their primary energy, the stau tracks appear like low-energy
muons in the detector. A potential signal of staus would thus be an excess over
muon tracks induced by atmospheric muon neutrinos. Our analysis focuses on the
region around the horizon as here the ratio between stau signal and atmospheric
background is largest. We will present the first sensitivity to constrain the
stau mass using IceCube and demonstrate the potential of this analysis with
future improvements.
