Hans Kraus

Abstract:

The EDELWEISS-II collaboration has performed a direct search for WIMP dark matter with an array of ten 400 g heat-and-ionization cryogenic detectors equipped with interleaved electrodes for the rejection of near-surface events. Results from eleven months of continuous operation at the Laboratoire Souterrain de Modane are shown and their interpretation in terms of limits on the cross-section of spin-independent interactions of WIMPs and nucleons presented. The result obtained demonstrates the excellent background rejection capabilities of these simple and robust detectors in an actual WIMP search experiment. © 2012 American Institute of Physics.

Abstract:

Motivated by the recent interest in light weakly interacting massive particles (WIMPs) of mass ∼O(10GeV/c2), an extension of the elastic, spin-independent, WIMP-nucleon cross-section limits resulting from the CRESST-II commissioning run (2007) are presented. Previously, these data were used to set cross-section limits from 1000GeV/c2 down to ∼17GeV/c2, using tungsten recoils, in 47.9 kg-days of exposure of calcium tungstate. Here, the overlap of the oxygen and calcium bands with the acceptance region of the commissioning run data set is reconstructed using previously published quenching factors. The resulting elastic WIMP cross-section limits, accounting for the additional exposure of oxygen and calcium, are presented down to 5GeV/c2. © 2012 American Physical Society.