VORTEX PAIRS IN CHARGED FLUIDS

The motion of a vortex-(anti)vortex pair is studied numerically in the framework of a dynamical Ginzburg-Landau model, relevant to the descr iption of a superconductor or of an idealized bosonic plasma. It is sh own that up to a fine ''cyclotron'' internal motion, also studied in d etail, two vortices that are brought together rotate around each other , while a vortex and an antivortex move in formation parallel to each other. The velocities of the vortices in both cases are measured to be in remarkable agreement with recent theoretical predictions, down to intervortex distances as small as their characteristic diameter.