The Solar Solution: Tracking the Sun with Low Energy Neutrinos

TL;DR

This paper explores the potential of using neutrino-electron scattering in terrestrial detectors to determine the direction of low-energy solar neutrinos, aiding in distinguishing them from dark matter signals.

Contribution

It introduces a simple simulation demonstrating that a significant fraction of ejected electrons from neutrino interactions point back to the neutrino source, enabling directional detection.

Findings

68% of ejected electrons are within 0.99 radians of neutrino direction

Simulation suggests feasibility of low-energy neutrino directional detection

Potential to improve background discrimination in dark matter experiments

Abstract

As neutrinos become a significant background for projected dark matter experiments, the community will become concerned with determining if events counted in a dark matter experiment are good dark matter candidates or low-energy neutrinos from astrophysical sources. We investigate the feasibility of using neutrino-electron scattering in a terrestrial detector medium as a means to determine the flight direction of the original, low-energy solar neutrino.Using leading-order weak interactions in the Standard Model and constrains from energy and momentum conservation, we developed a simple simulation that suggests that 68% of the time the ejected electron would be within 0.99 radians of the incident neutrino's direction. This suggests that it may be fruitful to pursue low-energy neutrino detection capability that can utilize such ejected electrons.