Quantized vortex rings in superfluid He4 and Light Dark Matter

The possibility is considered that, after nuclear recoil caused by elastic scattering with Light Dark Matter, atoms in superfluid He4 may create quantized vortex rings, which can thereafter be detected. The concept for sort of telescope for LDM is presented, which would be sensitive to its motion through the Galactic LDM wind. A demonstrator is proposed, which makes use of thermal neutrons.