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arXiv · 1309.1005

Evolution of Neutron-Initiated Micro-Big-Bang in superfluid He 3B

Yuri Bunkov·Andrei Golov·Victor L'vov·Anna Pomyalov·Itamar Procaccia
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Abstract

A nuclear capture reaction of a single neutron by ultra-cold superfluid $^3$He results in a rapid overheating followed by the expansion and subsequent cooling of the hot subregion, in a certain analogy with the Big Bang of the early Universe. It was shown in a Grenoble experiment that a significant part of the energy released during the nuclear reaction was not converted into heat even after several seconds. It was thought that the missing energy was stored in a tangle of quantized vortex lines. This explanation, however, contradicts the expected lifetime of a bulk vortex tangle, $10^{-5}-10^{-4}\,$s, which is much shorter than the observed time delay of seconds. In this Letter we propose a scenario that resolves the contradiction: the vortex tangle, created by the hot spot, emits isolated vortex loops that take with them a significant part of the tangle's energy. These loops quickly reach the container walls. The dilute ensemble of vortex loops attached to the walls can survive for a long time, while the remaining bulk vortex tangle decays quickly.

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Yuri Bunkov, Andrei Golov, Victor L'vov, Anna Pomyalov, Itamar Procaccia. 2013-09-04. Evolution of Neutron-Initiated Micro-Big-Bang in superfluid He 3B. https://doi.org/10.1103/physrevb.90.024508

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