Hybrid detection of high-energy cosmic neutrinos with the next-generation neutrino detectors at the South Pole

TL;DR

This paper explores the potential of hybrid detection methods combining radio and optical signals in next-generation neutrino detectors at the South Pole, aiming to improve high-energy cosmic neutrino observations.

Contribution

It provides the first calculation of expected event rates for a hybrid radio-optical neutrino detection system near IceCube-Gen2, demonstrating feasibility and potential detection improvements.

Findings

Approximately 1 event per year expected with 10 radio stations

Radio detectors could lower energy threshold to ~PeV

Hybrid detection enhances high-energy neutrino observation capabilities

Abstract

In 2013 the IceCube collaboration announced the discovery of a cosmic neutrino flux up to PeV energies, validating neutrino astronomy as the next promising observational technique to explore the high-energy Universe. The neutrino community is moving forward with the construction of new facilities to enhance the detection of these elusive particles at higher energies (up to and beyond EeV) and to increase the statistics at the high-energy end of the IceCube neutrino flux. Future large volume neutrino detectors, using both the radio Askaryan and the optical Cherenkov signal, will open the possibility of hybrid detection of neutrino interactions within the polar ice. In this contribution we present a first calculation of the expected number of events for a simplified geometry of one radio station located at 200 m depth in the vicinity of a ~10 km^3 in-ice Cherenkov detector, similar to the planned IceCube-Gen2 neutrino observatory. Preliminary simulations show that a total event rate of ~1 event/year is achievable for a 10-stations array assuming that the Askaryan radio detectors can lower their energy threshold down to ~PeV energies. Such a possibility is currently under study for the future radio extension foreseen as one of the surface components of IceCube-Gen2.