Physics from solar neutrinos in dark matter direct detection experiments

International audienceThe next generation of dark matter direct detection experiments will besensitive to both coherent neutrino-nucleus and neutrino-electron scattering.This will enable them to explore aspects of solar physics, perform the lowestenergy measurement of the weak angle to date, and probe contributions from newtheories with light mediators. In this article, we compute the projectednuclear and electron recoil rates expected in several dark matter directdetection experiments due to solar neutrinos, and use these estimates toquantify errors on future measurements of the neutrino fluxes, weak mixingangle and solar observables, as well as to constrain new physics in theneutrino sector. Our analysis shows that the combined rates of solar neutrinoevents in second generation experiments (SuperCDMS and LZ) can yield ameasurement of the $pp$ flux to 2.5% accuracy via electron recoil, and slightlyimprove the $^8$B flux determination. Assuming a low-mass argon phase,projected tonne-scale experiments like DARWIN can reduce the uncertainty onboth the $pp$ and boron-8 neutrino fluxes to below 1%. Finally, we use currentresults from LUX, SuperCDMS and CDMSlite to set bounds on new interactionsbetween neutrinos and electrons or nuclei, and show that future directdetection experiments can be used to set complementary constraints on theparameter space associated with light mediators