First Dark Matter Search Results from the XENON1T Experiment

TLDR

The blinded search analyzed 34.2 live days of data collected from November 2016 to January 2017. We report the first dark‑matter search results from XENON1T, a ∼2000‑kg dual‑phase xenon TPC at LNGS, achieving the lowest electronic‑recoil background of (1.93 ± 0.25) × 10⁻⁴ events/(kg·day·keVₑₑ) in the 5–40 keV_nr range and setting the most stringent spin‑independent WIMP‑nucleon cross‑section limits, reaching 7.7 × 10⁻⁴⁷ cm² at 35 GeV/c².

Abstract

We report the first dark matter search results from XENON1T, a ∼2000-kg-target-mass dual-phase (liquid-gas) xenon time projection chamber in operation at the Laboratori Nazionali del Gran Sasso in Italy and the first ton-scale detector of this kind. The blinded search used 34.2 live days of data acquired between November 2016 and January 2017. Inside the (1042±12)-kg fiducial mass and in the [5,40] keV_{nr} energy range of interest for weakly interacting massive particle (WIMP) dark matter searches, the electronic recoil background was (1.93±0.25)×10^{-4} events/(kg×day×keV_{ee}), the lowest ever achieved in such a dark matter detector. A profile likelihood analysis shows that the data are consistent with the background-only hypothesis. We derive the most stringent exclusion limits on the spin-independent WIMP-nucleon interaction cross section for WIMP masses above 10 GeV/c^{2}, with a minimum of 7.7×10^{-47} cm^{2} for 35-GeV/c^{2} WIMPs at 90% C.L.