The nature of Dark Matter in the universe remains a mystery. Experiments so far have not been able to directly prove that Dark Matter even exists, despite ample cosmological evidence indicating that it makes up 85% of the matter in the universe. The DEAP-3600 experiment is looking for the signature of Dark Matter particles from our galactic halo scattering on the detector's 3.3 tonne liquid argon target. Located in an active mine at a depth of 2 km, the DEAP-3600 detector has been taking data for 3 years and is among the most sensitive currently running detectors for detecting Dark Matter in the form of weakly interacting particles (WIMPs) of masses above 30 GeV/c^2.
The interaction cross section between the hypothetical WIMPs and atomic nuclei must be very small. Experimenters must go to extreme lengths to build detectors sensitive to scattering cross sections well below 10^-40 cm^2, that nevertheless are free of background events from natural radioactivity.
This talk will present the design and underground construction of the DEAP-3600 detector in the light of achieving stable, background-free operation, as well as analysis highlights of the data taken so far.
The DEAP-3600 detector is followed by the DarkSide-20k detector currently under construction. The design and physics reach of this upcoming project, as well as its relevance in the direct detection field, will be discussed.