  WIMPs (Weakly Interacting Massive Particles) are considered the main
candidates for Cold Dark Matter. The ArDM experiment aims at measuring signals
directly induced by WIMPs in liquid argon. A 1-ton prototype is currently
developed with the goal of demonstrating the feasibility and performance of a
detector with such a large target mass. ArDM aims at acting as a liquid argon
TPC and additionally measuring the scintillation light. The principle of the
experiment and the conceptual design of the detector are described.
