The Double Chooz experiment presents an indication of reactor electron antineutrino disappearance consistent with neutrino oscillations. An observed-to-predicted ratio of events of $0.944\pm 0.016(\mathrm{stat})\pm 0.040(\mathrm{syst})$ was obtained in 101 days of running at the Chooz nuclear power plant in France, with two $4.25{\mathrm{GW}}_{\mathrm{th}}$ reactors. The results were obtained from a single $10{\mathrm{m}}^3$ fiducial volume detector located 1050 m from the two reactor cores. The reactor antineutrino flux prediction used the Bugey4 flux measurement after correction for differences in core composition. The deficit can be interpreted as an indication of a nonzero value of the still unmeasured neutrino mixing parameter ${sin}^{2}2{\theta }_{13}$. Analyzing both the rate of the prompt positrons and their energy spectrum, we find ${sin}^{2}2{\theta }_{13}=0.086\pm 0.041(\mathrm{stat})\pm 0.030(\mathrm{syst})$, or, at 90% C.L., $0.017<{sin}^{2}2{\theta }_{13}<0.16$.

We present the results of a search for dark matter weakly interacting massive particles (WIMPs) in the mass range below $20\mathrm{GeV}/c^2$ using a target of low-radioactivity argon with a 6786.0 kg d exposure. The data were obtained using the DarkSide-50 apparatus at Laboratori Nazionali del Gran Sasso. The analysis is based on the ionization signal, for which the DarkSide-50 time projection chamber is fully efficient at $0.1\mathrm{keV}\text{ee}$. The observed rate in the detector at $0.5\mathrm{keV}\text{ee}$ is about $1.5\mathrm{event}/\mathrm{keV}\text{ee}/\mathrm{kg}/\mathrm{d}$ and is almost entirely accounted for by known background sources. We obtain a 90% C.L. exclusion limit above $1.8\mathrm{GeV}/c^2$ for the spin-independent cross section of dark matter WIMPs on nucleons, extending the exclusion region for dark matter below previous limits in the range $1.8–6\mathrm{GeV}/c^2$.

The XENON10 experiment at the Gran Sasso National Laboratory uses a 15 kg xenon dual phase time projection chamber to search for dark matter weakly interacting massive particles (WIMPs). The detector measures simultaneously the scintillation and the ionization produced by radiation in pure liquid xenon to discriminate signal from background down to 4.5 keV nuclear-recoil energy. A blind analysis of 58.6 live days of data, acquired between October 6, 2006, and February 14, 2007, and using a fiducial mass of 5.4 kg, excludes previously unexplored parameter space, setting a new 90% C.L. upper limit for the WIMP-nucleon spin-independent cross section of $8.8\times {10}^{-44}{\mathrm{cm}}^2$ for a WIMP mass of $100\mathrm{GeV}/c^2$, and $4.5\times {10}^{-44}{\mathrm{cm}}^2$ for a WIMP mass of $30\mathrm{GeV}/c^2$. This result further constrains predictions of supersymmetric models.

We present results from the direct search for dark matter with the XENON100 detector, installed underground at the Laboratori Nazionali del Gran Sasso of INFN, Italy. XENON100 is a two-phase time-projection chamber with a 62 kg liquid xenon target. Interaction vertex reconstruction in three dimensions with millimeter precision allows the selection of only the innermost 48 kg as the ultralow background fiducial target. In 100.9 live days of data, acquired between January and June 2010, no evidence for dark matter is found. Three candidate events were observed in the signal region with an expected background of ($1.8\pm 0.6$) events. This leads to the most stringent limit on dark matter interactions today, excluding spin-independent elastic weakly interacting massive particle (WIMP) nucleon scattering cross sections above $7.0\times {10}^{-45}{\mathrm{cm}}^2$ for a WIMP mass of $50\mathrm{GeV}/c^2$ at 90% confidence level.

We report results of a search for light ($\lesssim 10\mathrm{GeV}$) 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 ${\sigma }_n>7\times {10}^{-42}{\mathrm{cm}}^2$, for a dark matter particle mass $m_{\chi }=7\mathrm{GeV}$. 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.