Sonic pulses from crossed vorteces in liquid helium-four: A simulation of high energy radiation from crossed cosmic strings

The crossing and recombination of two cosmic strings, left from the evoluti on of the early universe, is a likely source of ultra-high energy quanta. I t is proposed that, as an analogue, the crossing of two vortices in superfl uid Helium-four might generate sound pulses that would be detectable in a l aboratory experiment. A simple model yields a prediction for the spectrum: quanta per element of solid angle and energy inversely proportional to ener gy.