Neutrino direction and energy resolution of Askaryan detectors

TL;DR

This paper discusses techniques for reconstructing the direction and energy of high-energy neutrinos detected via radio signals in ice, emphasizing the resolution capabilities of Askaryan detectors like ARA and ARIANNA.

Contribution

It introduces and quantifies new reconstruction algorithms for neutrino direction and energy using radio detection data and detailed Monte Carlo simulations.

Findings

Neutrino direction can be reconstructed with high precision using signal polarization and timing.

Neutrino energy estimation benefits from frequency spectrum analysis and vertex distance measurement.

The proposed methods achieve promising resolution levels for large-scale Askaryan detectors.

Abstract

Detection of high-energy neutrinos via the radio technique allows for an exploration of the neutrino energy range from $\sim10^{16}$\~eV to $\sim10^{20}$\~eV with unprecedented precision. These Askaryan detectors have matured in two pilot arrays (ARA and ARIANNA) and the construction of a large-scale detector is actively discussed in the community. In this contribution, we present reconstruction techniques to determine the neutrino direction and energy from the observed few-nanoseconds short radio flashes and quantify the resolution of one of such detectors. The reconstruction of the neutrino direction requires a precise measurement of both the signal direction as well as the signal polarization. The reconstruction of the neutrino energy requires, in addition, the measurement of the vertex distance, obtainable from the time difference of two signal paths through the ice, and the viewing angle of the in-ice shower via the frequency spectrum. We discuss the required algorithms and quantify the resolution using a detailed Monte Carlo simulation study.