Calculated solar-neutrino capture rate for a radiochemical 205 Tl-based solar-neutrino detector

TL;DR

This paper calculates the solar-neutrino capture rate for a 50Tl-based radiochemical detector, revealing a lower rate than previous estimates, and highlights its potential for low-energy solar-neutrino detection.

Contribution

First calculation of the charged-current solar-neutrino scattering cross section for 50Tl, providing new insights into its detection capabilities.

Findings

Capture rate of 62.2 8 8.6 SNU for 50Tl.

Significantly smaller capture rate than previous estimates.

Potential for low-energy solar-neutrino detection using 50Tl.

Abstract

Radiochemical experiments for low-energy solar-neutrino detection have been making headlines by exploiting the isotopes \iso{Cl}{37} and \iso{Ga}{71}. Such a very low-threshold measurement of this type can also be performed using \iso{Tl}{205}, which has been considered for decades for this purpose. A unique feature of this detector nucleus is the integration is the solar-neutrino flux over millions of years owing to its long-living daughter \iso{Pb}{205}. In this study we have calculated for the first time the cross section for the charged-current solar-neutrino scattering off \iso{Tl}{205}. Taking into account the solar-model-predicted neutrino fluxes and the electron-neutrino survival probabilities, a solar-neutrino capture rate of 62.2 $\pm 8.6$ SNU is determined, a value significantly smaller than in previous estimates.