Development of a method for determining the search window for solar flare neutrinos

TL;DR

This paper introduces a method to define temporal search windows for solar flare neutrinos using satellite data, aiming to enhance neutrino detection sensitivity amidst background noise.

Contribution

A novel approach utilizing satellite observations to accurately determine search windows for solar flare neutrino detection, improving background discrimination.

Findings

Average search windows: 4178 s for soft X-ray, 700 s for derivative, 944 s for hard X-ray, 1586 s for neutron capture gamma-rays, 776 s for high-energy hard X-ray.

Analyzed 23 solar flares above X5.0 class from 1996-2018.

Method enhances neutrino detectors' ability to identify solar flare neutrinos.

Abstract

Neutrinos generated during solar flares remain elusive. However, after $50$ years of discussion and search, the potential knowledge unleashed by their discovery keeps the search crucial. Neutrinos associated with solar flares provide information on otherwise poorly known particle acceleration mechanisms during solar flare. For neutrino detectors, the separation between atmospheric neutrinos and solar flare neutrinos is technically encumbered by an energy band overlap. To improve differentiation from background neutrinos, we developed a method to determine the temporal search window for neutrino production during solar flares. Our method is based on data recorded by solar satellites, such as Geostationary Operational Environmental Satellite (GOES), Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI), and GEOTAIL. In this study, we selected 23 solar flares above the X5.0 class that occurred between 1996 and 2018. We analyzed the light curves of soft X-rays, hard X-rays, $\gamma$-rays, line $\gamma$-rays from neutron capture as well as the derivative of soft X-rays. The average search windows are determined as follows: $4,178$ s for soft X-ray, $700$ s for derivative of soft X-ray, $944$ s for hard X-ray ($100$-$800$ keV), $1,586$ s for line $\gamma$-ray from neutron captures, and $776$ s for hard X-ray (above $50$ keV). This method allows neutrino detectors to improve their sensitivity to solar flare neutrinos.