Dark Matter Results from 100 Live Days of XENON100 Data

TL;DR

This paper reports on the XENON100 experiment's 100-day search for dark matter, setting the most stringent limits on WIMP-nucleon interactions to date, with no confirmed dark matter detection.

Contribution

First detailed results from the XENON100 detector using 100 live days, providing the tightest constraints on dark matter particle interactions.

Findings

No dark matter signals observed.

Set new upper limits on WIMP-nucleon cross-section.

Observed 3 candidate events against an expected background of 1.8.

Abstract

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 to select only the innermost 48 kg as ultra-low 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 a pre-defined signal region with an expected background of 1.8 +/- 0.6 events. This leads to the most stringent limit on dark matter interactions today, excluding spin-independent elastic WIMP-nucleon scattering cross-sections above 7.0x10^-45 cm^2 for a WIMP mass of 50 GeV/c^2 at 90% confidence level.