Search for Light Dark Matter in XENON10 Data

We report results of a search for light ($ensuremath{lesssim}10text{ }text{ }mathrm{GeV}$) particle dark matter with the XENON10 detector. The event trigger was sensitive to a single electron, with the analysis threshold of 5 electrons corresponding to 1.4 keV nuclear recoil energy. Considering spin-independent dark matter-nucleon scattering, we exclude cross sections ${ensuremath{sigma}}_{n}>7ifmmodetimeselsetexttimesfi{}{10}^{ensuremath{-}42}text{ }text{ }{mathrm{cm}}^{2}$, for a dark matter particle mass ${m}_{ensuremath{chi}}=7text{ }text{ }mathrm{GeV}$. We find that our data strongly constrain recent elastic dark matter interpretations of excess low-energy events observed by CoGeNT and CRESST-II, as well as the DAMA annual modulation signal.