Status of the EDELWEISS-II experiment

TL;DR

The paper reports on the status and recent commissioning results of the EDELWEISS-II experiment, a low-background underground search for dark matter WIMPs using Ge detectors with active surface event rejection.

Contribution

It introduces two new detector types with active surface event rejection, enhancing the experiment's sensitivity to rare nuclear recoils.

Findings

Commissioned second phase with over 7 kg of Ge detectors.

Developed and tested two new detector types with active surface event rejection.

Aimed to achieve a 10-8 pb cross-section measurement sensitivity.

Abstract

EDELWEISS is a direct dark matter search experiment situated in the low radioactivity environment of the Modane Underground Laboratory. The experiment uses Ge detectors at very low temperature in order to identify eventual rare nuclear recoils induced by elastic scattering of WIMPs from our Galactic halo. We present results of the commissioning of the second phase of the experiment, involving more than 7 kg of Ge, that has been completed in 2007. We describe two new types of detectors with active rejection of events due to surface contamination. This active rejection is required in order to achieve the physics goals of 10-8 pb cross-section measurement for the current phase.