Description

We report the first dark matter search results from XENON1T, a~2000 kg dual-phase xenon time projection chamber in operation at the Laboratori Nazionali del Gran Sasso in Italy, 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] keVnr energy range of interest for WIMP dark matter searches, the electronic recoil background was (1.93±0.25)x10−4 events/(kg x day x keVee), the lowest ever achieved in a dark matter detector. A profile likelihood analysis shows that the data is 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/c2, with a minimum of 7.7 x10−47 cm2 for 35-GeV/c2 WIMPs at 90% confidence level.

In the full nominal 2 t y exposure, we expect to reach with XENON1T a sensitivity of 1.6 x10−47 cm2.

We will also present the future upgrade of the detector, XENONnT, with increased active mass and lower background, to foresee another order of magnitude improvement in sensitivity by 2024.

First Results from the XENON1T Dark Matter Experiment at LNGS

by Marco Selvi (BO)

aula 131