The Space Climate Research Group at the University of Oulu, Finland has been studying the effects of energetic particle precipitation from space, more commonly known as the aurora borealis or Northern ...

One of the main features of superfluids is the presence of topological defects with quantised circulation. These objects are known as quantum vortices and exhibit a hydrodynamic behaviour. Nowadays, ...

We report an experimental study of the 2D dynamics of active particles driven by quantum vortices on the free surface of superfluid helium at T = 1.45 К. The particle motion at short times (< 25 ms) ...