Results from the Cryogenic Dark Matter Search experiment

Understand

The Cryogenic Dark Matter Search experiment uses low-temperature solid-state detectors to seek Weakly Interacting Massive Particles (WIMPs) and has the world's best exclusion limit on the spin-independent WIMP-nucleon cross section.

• The experiment uses ionization and athermal phonon signals from particle interactions to discriminate between candidate (nuclear recoil) and background (electron recoil) events with extremely high efficiency.
• The detectors' low energy threshold for electron recoil events allows us to perform the search for relic axions and solar axions which can interact in the detector via the axio-electric coupling $g_{a\bar{e}e}$ and the Primakoff coupling $g_{a\gamma\gamma}$ respectively.
• We describe the experiment and our most recent results from the Soudan 5-tower data runs which include a world-leading upper limit on the WIMP-nucleon spin-independent cross section with a minimum of $4.6\times10^{-44}$ cm$^{2}$ at the 90% confidence level (CL) for a 60 GeV/c$^{2}$ WIMP, the world-leading experimental upper limit on the axio-electric coupling of $1.4\times10^{-12}$ at the 90% CL for a 2.5 keV/c$^{2}$ axion, and the upper limit on the axion-photon coupling of $2.4\times10^{-9}$ GeV$^{-1}$ at the 95% CL.