DUNE as the Next-Generation Solar Neutrino Experiment.

We show that the Deep Underground Neutrino Experiment (DUNE), with significant but feasible new efforts, has the potential to deliver world-leading results in solar neutrinos. With a 100  kton-yr exposure, DUNE could detect ≳10^{5} signal events above 5 MeV electron energy. Separate precision measurements of neutrino-mixing parameters and the ^{8}B flux could be made using two detection channels (ν_{e}+^{40}Ar and ν_{e,μ,τ}+e^{-}) and the day-night effect (>10σ). New particle physics may be revealed through the comparison of solar neutrinos (with matter effects) and reactor neutrinos (without), which is discrepant by ∼2σ (and could become 5.6σ). New astrophysics may be revealed through the most precise measurement of the ^{8}B flux (to 2.5%) and the first detection of the hep flux (to 11%). DUNE is required: No other experiment, even proposed, has been shown capable of fully realizing these discovery opportunities.