A search for ultrahigh-energy neutrinos associated with astrophysical sources using the third flight of ANITA

TL;DR

This paper describes a methodology for detecting ultra high-energy neutrinos from astrophysical sources using ANITA's third flight data, applying it to various source classes, and setting upper limits on neutrino fluxes.

Contribution

The paper introduces a new analysis method for associating neutrino signals with astrophysical sources in ANITA data, including application to multiple source classes and setting upper limits.

Findings

One candidate neutrino event associated with SN 2015D but not statistically significant.

Upper limits established for neutrino emissions from various astrophysical sources.

Methodology applicable to future more sensitive neutrino detection instruments.

Abstract

The ANtarctic Impulsive Transient Antenna (ANITA) long-duration balloon experiment is sensitive to interactions of ultra high-energy (E > 10^{18} eV) neutrinos in the Antarctic ice sheet. The third flight of ANITA, lasting 22 days, began in December 2014. We develop a methodology to search for energetic neutrinos spatially and temporally coincident with potential source classes in ANITA data. This methodology is applied to several source classes: the TXS 0506+056 blazar and NGC 1068, the first potential TeV neutrino sources identified by IceCube, flaring high-energy blazars reported by the Fermi All-Sky Variability Analysis, gamma-ray bursts, and supernovae. Among searches within the five source classes, one candidate was identified as associated with SN 2015D, although not at a statistically significant level. We proceed to place upper limits on the source classes. We further comment on potential applications of this methodology to more sensitive future instruments.