The ArDM (Argon Dark Matter) Experiment was a particle physics experiment based on a liquid argon detector, aiming at measuring signals from WIMPs (Weakly Interacting Massive Particles), which may constitute the Dark Matter in the universe. Elastic scattering of WIMPs from argon nuclei is measurable by observing free electrons from ionization and photons from scintillation, which are produced by the recoiling nucleus interacting with neighbouring atoms. The ionization and scintillation signals can be measured with dedicated readout techniques, which constituted a fundamental part of the detector.
In order to get a high enough target mass the noble gas argon was used in the liquid phase as target material. Since the boiling point of argon is at 87 K at normal pressure, the operation of the detector required a cryogenic system.
The ArDM experiment ended in 2019 when data taking was stopped and the experiment's apparatus decommissioned. The ArDM experiment's apparatus was then reused for another physics experiment, DArT (part of the DarkSide program), at Canfranc Underground Laboratory.[1]
ArDM did not find signals of dark matter particles.