ecCNO Solar Neutrinos: A Challenge for Gigantic Ultra-Pure Liquid Scintillator Detectors

TL;DR

This paper discusses the potential to detect rare ecCNO solar neutrinos using future large ultra-pure liquid scintillator detectors, which could reveal insights into the solar core's metallicity and neutrino properties.

Contribution

It proposes that future gigantic ultra-pure liquid scintillator detectors could measure the elusive ecCNO neutrinos, providing new information on solar composition and neutrino physics.

Findings

Detection of ecCNO neutrinos is challenging but potentially feasible with future detectors.

Measuring ecCNO neutrinos can inform on solar metallicity.

This approach probes the solar neutrino transition region at around 2.5 MeV.

Abstract

Neutrinos produced in the Sun by electron capture reactions on $^{13}{\rm N}$, $^{15}{\rm O}$ and $^{17}{\rm F}$, to which we refer as ecCNO neutrinos, are not usually considered in solar neutrino analysis since the expected fluxes are extremely low. The experimental determination of this sub-dominant component of the solar neutrino flux is very difficult but could be rewarding since it provides a determination of the metallic content of the solar core and, moreover, probes the solar neutrino survival probability in the transition region at $E_\nu\sim 2.5\,{\rm MeV}$. In this letter, we suggest that this difficult measure could be at reach for future gigantic ultra-pure liquid scintillator detectors, such as LENA.