As direct dark matter experiments continue to increase in size, they will
become sensitive to neutrinos from astrophysical sources. For experiments that
do not have directional sensitivity, coherent neutrino scattering (CNS) from
several sources represents an important background to understand, as it can
almost perfectly mimic an authentic WIMP signal. Here we explore in detail the
effect of neutrino backgrounds on the discovery potential of WIMPs over the
entire mass range of 500 MeV to 10 TeV. We show that, given the theoretical and
measured uncertainties on the neutrino backgrounds, direct detection
experiments lose sensitivity to light (~10 GeV) and heavy (~100 GeV) WIMPs with
a spin-independent cross section below 10^{-45} cm^2 and 10^{-49} cm^2,
respectively.Comment: 15 pages, 12 figures, 7Be fluxes revised, conclusions unchange
