Search for exotic interactions of solar neutrinos in the CDEX-10 experiment

We investigate exotic neutrino interactions using the 205.4 kg$\cdot$day dataset from the CDEX-10 experiment at the China Jinping Underground Laboratory. New constraints on the mass and couplings of new gauge bosons are presented. Two nonstandard neutrino interactions are considered: a $U(1{)}_{B-L}$ gauge-boson-induced interaction between an active neutrino and electron/nucleus, and a dark-photon-induced interaction between a sterile neutrino and electron/nucleus via kinetic mixing with a photon. This work probes an unexplored parameter space involving sterile neutrino coupling with a dark photon. New laboratory limits are derived on dark photon masses below $1\mathrm{e}\mathrm{V}\mathrm{/}{c}^2$ at some benchmark values of $\mathrm{\Delta }{m}_{41}^2$ and $g^{\mathrm{\prime }2}{\mathrm{s}\mathrm{i}\mathrm{n}}^{2}2{\theta }_{14}$.