Towards Radio Searches for the Highest-Energy Tau Neutrinos with BEACON*

When ultrahigh energy tau neutrinos skim the Earth, the tau leptons they produce can exit the Earth and produce extensive air showers in the atmosphere. The Beamforming Elevated Array for COsmic Neutrinos (BEACON) is a novel detector concept consisting of many radio interferometers placed on mountaintops, designed to detect the radio emission of these upgoing extensive air showers. The prototype is located at the White Mountain Research Station in California and consists of a phased array of 4 custom crossed-dipole antennas with a 30-80 MHz bandwidth. A goal of the prototype is the detection of cosmic rays, whose well known flux will allow us to estimate the sensitivity of a full-size BEACON to ultrahigh energy neutrinos. In this talk, we discuss the current status of the BEACON prototype, a recent calibration campaign using a drone, and the ongoing cosmic ray search.