Abstract
In gauge-mediated models, the next-to-lightest supersymmetric particle (NLSP), may travel a long distance before decaying into a gravitino and a photon. The collider experiment is not able to distinguish such a scenario from the usual supergravity models when the decay time of the NLSP is long enough. Here we propose a new method to detect such a long decay of the NLSP. The high energy cosmic rays hitting the atmosphere will produce a lot of SUSY particles, which decay promptly into the NLSP. The can travel a distance of the order of the atmosphere and decays into a photon and a gravitino. We suggest to use the ground-based arrays of telescopes to detect the photon. This method can probe a SUSY breaking scale sqrt(<F>) ~ 10^4~10^6 GeV. The event rate could be as high as O(10^(-4)) per km^2 per year per sr.