Constraining the Sensitivity of BEACON with Scintillating Calibration Devices

The Beamforming Elevated Array for COsmic Neutrinos (BEACON) is a tau neutrino observatory concept consisting of many mountaintop phased radio antenna arrays. BEACON detects tau neutrinos of the highest energies (> 100 PeV) by searching for radio signals that are emitted by the extensive particle air showers (EAS) they initiate. Scintillators are being used in the BEACON prototype to calibrate the radio instruments and validate cosmic ray events. Before comparisons can be made with radio measurements, the scintillators must be calibrated against the known cosmic ray flux. Muons from cosmic ray EAS are measured across a large number of events to identify the MIP peak. Using the Geant4 simulation package, interactions between MIP peak muons and a modeled scintillator are calculated according to the expected zenith angle distribution. These simulations yield the expected energy deposition by MIP peak muons. From the measurements and simulations, muon energy and energy deposition into the scintillator can be reconstructed from a given scintillator signal. Consequently, expected scintillator signal from a given cosmic ray EAS can be calculated. Simulated signal responses in the radio antennas and the scintillators at the BEACON prototype site for given cosmic ray showers are being compared to gain greater insight into the radio response to EAS. Here, we present the results of scintillator calibration at BEACON and discuss how scintillators can be used to refine radio-only detection.