Institute of research into the fundamental laws of the Universe

Objectives

The goal of Edelweiss is to detect the dark matter of our Galaxy through its interactions in detectors operated in underground laboratory.

The EROS experiment, searching for massive compact objects in our galaxy, showed that at most 7 % of our local missing mass could be accounted for by such objects, that is by ordinary matter.

Most of dark matter could then be constituted of WIMPs (Weakly Interacting Massive Particles), a generic name given to these particles forming an extended spherical halo around our galaxy.

Supersymetric theories provide an ideal candidate, the neutralino, the lightest stable particle in most models.

Edelweiss goal is then to detect such particles by their interactions in detectors able to discriminate the induced nuclear recoils against the overwhelming background of electronic recoils, due to natural radioactiviy.

In a first phase involving 3 detectors of 300 g, Eelweiss had obtained the best sensitivity to the presence of WIMPs in 2002.

Thanks to a copmpletetly new set-up, recently installed and validated in LSM, with 28 and in a next step 68 detectors, Edelweiss will be able to increase its sensitivity by a factor 100 in the two years to come.