Propagation of supersymmetric charged sleptons at high energies

The potential for neutrino telescopes to discover charged stau production in neutrino-nucleon interactions in Earth depends in part on the stau lifetime and range. In some supersymmetric scenarios, the next lightest supersymmetric particle is a stau with a decay length on the scale of 10 km. We evaluate the electromagnetic energy loss as a function of energy and stau mass. The energy loss parameter $\beta$ scales as the inverse stau mass for the dominating electromagnetic processes, photonuclear and $e^+e^-$ pair production. The range can be parameterized as a function of stau mass, initial energy and minimum final energy. In comparison to earlier estimates of the stau range, our results are as much as a factor of two larger, improving the potential for stau discovery in neutrino telescopes.