ecCNO solar neutrinos: A challenge for gigantic ultra-pure liquid scintillator detectors

Neutrinos produced in the Sun by electron capture reactions on N-13, O-15 and F-17, 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 similar to 2.5 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. (C) 2015 The Author. Published by Elsevier B.V.