New Results from the Cryogenic Dark Matter Search Experiment

TL;DR

The Cryogenic Dark Matter Search experiment used improved detectors and shielding to set stricter limits on WIMP interactions, excluding new parameter space for certain WIMP masses and confirming previous candidate events were likely neutrons.

Contribution

This paper presents new experimental results with enhanced detection methods that significantly improve limits on WIMP-nucleus scattering cross sections.

Findings

Stricter limits on WIMP cross sections for high masses.

Exclusion of new parameter space for WIMPs with 8-20 GeV/c^2 mass.

Confirmation that previous WIMP candidates were consistent with neutrons.

Abstract

Using improved Ge and Si detectors, better neutron shielding, and increased counting time, the Cryogenic Dark Matter Search (CDMS) experiment has obtained stricter limits on the cross section of weakly interacting massive particles (WIMPs) elastically scattering from nuclei. Increased discrimination against electromagnetic backgrounds and reduction of neutron flux confirm WIMP-candidate events previously detected by CDMS were consistent with neutrons and give limits on spin-independent WIMP interactions which are >2X lower than previous CDMS results for high WIMP mass, and which exclude new parameter space for WIMPs with mass between 8-20 GeV/c^2.