Obtaining supernova directional information using the neutrino matter oscillation pattern

TL;DR

This paper investigates how neutrino oscillation patterns affected by Earth's matter can be used to determine the direction of a supernova, especially when multiple detectors are combined, despite limitations compared to other methods.

Contribution

It introduces a novel approach to supernova localization using matter oscillation signatures in neutrino spectra, emphasizing the role of multiple detectors and energy resolution.

Findings

Oscillation patterns encode supernova direction information.

Multiple detectors improve pointing accuracy.

Method is complementary to existing neutrino detection techniques.

Abstract

A nearby core collapse supernova will produce a burst of neutrinos in several detectors worldwide. With reasonably high probability, the Earth will shadow the neutrino flux in one or more detectors. In such a case, for allowed oscillation parameter scenarios, the observed neutrino energy spectrum will bear the signature of oscillations in Earth matter. Because the frequency of the oscillations in energy depends on the pathlength traveled by the neutrinos in the Earth, an observed spectrum contains also information about the direction to the supernova. We explore here the possibility of constraining the supernova location using matter oscillation patterns observed in a detector. Good energy resolution (typical of scintillator detectors), well known oscillation parameters, and optimistically large (but conceivable) statistics are required. Pointing by this method can be significantly improved using multiple detectors located around the globe. Although it is not competitive with neutrino-electron elastic scattering-based pointing with water Cherenkov detectors, the technique could still be useful.