The Radar Echo Telescope for Cosmic Rays: Pathfinder experiment for a next-generation neutrino observatory

The Radar Echo Telescope for Cosmic Rays (RET-CR) is a recently initiated experiment designed to detect the englacial cascade of cosmic-ray air shower via in-ice radar, toward goal full-scale, next-generation ultra high energy neutrinos in polar ice. For cosmic rays with primary greater than 10 PeV, roughly 10% an air-shower's reaches surface elevation ice-sheet ($\gtrsim$2 km) concentrated into radius cm. This penetrating core creates many orders magnitude more dense preceding in-air cascade. can be detected radar echo technique, where transmitted radio reflected from ionization deposit left wake RET-CR will test method nature, air-shower serving as beam. We present projected event rate and sensitivity based upon three part simulation using CORSIKA, GEANT4, RadioScatter. expects $\sim$1 per day.