The neutrino floor at ultra-low threshold

Abstract: By lowering their energy threshold direct dark matter searches can reach the neutrino floor with experimental technology now in development. The 7Be flux can be detected with $\sim 10$ eV nuclear recoil energy threshold and 50 kg-yr exposure. The pep flux can be detected with $\sim 3$ ton-yr exposure, and the first detection of the CNO flux is possible with similar exposure. The pp flux can be detected with threshold of $\sim$ eV and only $\sim$ kg-yr exposure. These can be the first pure neutral current measurements of the low-energy solar neutrino flux. Measuring this flux is important for low mass dark matter searches and for understanding the solar interior.