The Beamforming Elevated Array for COsmic Neutrinos (BEACON): A Radio Detector for Earth-Skimming Tau Neutrinos

Abstract

When ultrahigh energy tau neutrinos skim the Earth, they can generate tau leptons that then decay in the atmosphere, forming upgoing extensive air showers. The Beamforming Elevated Array for COsmic Neutrinos (BEACON) is a novel detector concept that utilizes a mountaintop radio interferometer to search for the radio emission due to these extensive air showers. The prototype, located at the White Mountain Research Station in California, consists of 4 custom crossed-dipole antennas operating in the 30-80 MHz range and uses a directional interferometric trigger to achieve reduced thresholds and background rejection. The prototype will first be used to detect extensive air showers from down-going cosmic rays to validate the detector model. In this talk, we give an overview of the BEACON concept and the status of its prototype. We also discuss the ongoing cosmic ray search which utilizes both data analysis and simulation.

Detection of Radio Emission by Cosmic Rays with the BEACON Prototype

“…Detecting Cosmic Rays with BEACON A. Zeolla since 2018, there should be hundreds of detected cosmic rays among the hundreds of millions of RF-triggered events. Cranberry, the cosmic ray simulation for BEACON [8], determines the electric fields received by each antenna for a given extensive air shower through the interpolation of a library of ZHaireS [10] simulations. The electric fields are converted to voltages using the XFdtd simulated impedance and gain of the antennas, and then finally convolved with the amplifier and filter signal-chain.…”

“…Detecting Cosmic Rays with BEACON A. Zeolla and contains three 1-D convolution layers with filter sizes [128, 256, 128] and kernel sizes [3,8,8]. These hyperparameters were chosen using KerasTuner, which finds the optimal hyperparameters for a Keras model.…”

“…The current prototype consists of 4 crossed-dipole antennas with a 30-80 MHz bandwidth. While unlikely to detect tau neutrinos with only a single station, the BEACON prototype is expected to detect O (1) cosmic rays a day [8]. Cosmic rays produce downgoing EAS, which like the upgoing EAS of tau leptons, emit radio.…”