Probing neutrino magnetic moment at the Jinping neutrino experiment

Abstract

Neutrino magnetic moment ($\nu$MM) is an important property of massive neutrinos. The recent anomalous excess at few keV electronic recoils observed by the Xenon1T collaboration might indicate a $\sim 2.2\times 10^{-11}{\mu }_B$ effective neutrino magnetic moment (${\mu }_{\nu }^{eff}$) from solar neutrinos. Therefore, it is essential to carry out the $\nu$MM searches at a different experiment to confirm or exclude such hypothesis. We study the feasibility of doing $\nu$MM measurement with 4 kton active mass at Jinping neutrino experiment using electron recoil data from both natural and artificial neutrino sources. The sensitivity of ${\mu }_{\nu }^{eff}$ can reach $1.2\times 10^{-11}{\mu }_B$ at 90\% C.L. with 10-year data taking of solar neutrinos. Besides the intrinsic low energy background ${}^{14}$C in the liquid scintillator, we find the sensitivity to $\nu$MM is highly correlated with the systematic uncertainties of $pp$ and ${}^{85}$Kr. Reducing systematic uncertainties ($pp$ and ${}^{85}$Kr) and the intrinsic background (${}^{14}$C and ${}^{85}$Kr) can help to improve sensitivities below these levels and reach the region of astrophysical interest. With a 3 mega-Curie (MCi) artificial neutrino source ${}^{51}$Cr installed at Jinping neutrino detector for 55 days, it could give us a sensitivity to the electron neutrino magnetic moment (${\mu }_{{\nu }_e}$) with $1.1\times 10^{-11}{\mu }_B$ at 90\% C.L.. With the combination of those two measurements, the flavor structure of the neutrino magnetic moment can be also probed at Jinping.

Comments: 18 pages, 9 figures