XENON100 Dark Matter Results from a Combination of 477 Live Days

TL;DR

The XENON100 experiment analyzed 477 live days of data to set stringent limits on WIMP-nucleon scattering cross sections, significantly advancing dark matter detection sensitivity.

Contribution

This work combines three data runs and applies a blind analysis to improve constraints on WIMP interactions, providing the most sensitive limits to date for certain WIMP masses.

Findings

Set a minimum spin-independent WIMP-nucleon cross section of 1.1 × 10^{-45} cm^2 at 50 GeV/c^2.

Established upper limits on spin-dependent WIMP-neutron and WIMP-proton cross sections.

Achieved an ultra-low background level of approximately 5 × 10^{-3} events/(keV_ee·kg·day).

Abstract

We report on WIMP search results of the XENON100 experiment, combining three runs summing up to 477 live days from January 2010 to January 2014. Data from the first two runs were already published. A blind analysis was applied to the last run recorded between April 2013 and January 2014 prior to combining the results. The ultra-low electromagnetic background of the experiment, ~$5 \times 10^{-3}$ events/(keV$_{\mathrm{ee}}\times$kg$\times$day) before electronic recoil rejection, together with the increased exposure of 48 kg $\times$ yr improves the sensitivity. A profile likelihood analysis using an energy range of (6.6 - 43.3) keV$_{\mathrm{nr}}$ sets a limit on the elastic, spin-independent WIMP-nucleon scattering cross section for WIMP masses above 8 GeV/$c^2$, with a minimum of 1.1 $\times 10^{-45}$ cm$^2$ at 50 GeV/$c^2$ and 90% confidence level. We also report updated constraints on the elastic, spin-dependent WIMP-nucleon cross sections obtained with the same data. We set upper limits on the WIMP-neutron (proton) cross section with a minimum of 2.0 $\times 10^{-40}$ cm$^2$ (52$\times 10^{-40}$ cm$^2$) at a WIMP mass of 50 GeV/$c^2$, at 90% confidence level.