Towards Interferometric Triggering on Air Showers Induced by Tau Neutrino Interactions
2019 July 22
The Beamforming Elevated Array for COsmic Neutrinos (BEACON) Experiment aims to implement a new interferometric trigger targeting air showers initiated by the decay of tau leptons created during neutrino interactions in the earth at energies greater than 100 PeV. Over the past decade, interferometric techniques have been successfully implemented in analysis for many of the leading UHE particle experiments. BEACON has included interferometry at the trigger level, by implementing a beamforming technique in which signals are coherently summed, improving overall sensitivity and providing robust rejection against man-made backgrounds. A two-antenna short-term interferometer and a four-antenna long-term interferometer, both targeting the 30-80 MHz range, were installed on White Mountain near Bishop, California, as part of a months-long site study of man-made backgrounds and rates. Successfully suppressing man-made backgrounds will lead future iterations of BEACON to trigger on both cosmic rays from above and tau lepton air showers from tau neutrino interactions near the horizon.