Speaker
Description
The Askaryan Radio Array (ARA) is an ultra-high energy (UHE) neutrino detector at the South Pole that searches for impulsive broadband radio signals from neutrino-induced particle showers in glacial ice. ARA comprises five autonomous stations deployed at the South Pole, each instrumented with antennas deployed up to 200 meters below the ice surface and sensitive to both vertically and horizontally polarized signals. With over a decade of accumulated livetime, ARA provides the largest exposure yet achieved by any in-ice radio array.
We present the first array-wide diffuse UHE neutrino search using the ARA dataset taken from 2013 to 2023. Building on previous ARA analyses, this search benefits from substantial improvements in detector characterization and simulation, including data-driven models of noise and electronics, revised antenna responses, and upgraded neutrino interaction and lepton propagation modeling. Additionally, this search brings together the array-wide dataset within a unified analysis framework for waveform processing, background modeling, background rejection, and array-wide cut optimizations.
This search is expected either to identify the first UHE neutrino candidates observed by any in-ice radio neutrino detector, or to set the most stringent limits to date on the diffuse UHE neutrino flux above a few EeV. More broadly, this search informs the analysis and simulation strategies required for next-generation large-scale radio arrays such as RNO-G and IceCube-Gen2 Radio.