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arXiv · 1611.00505

Numerical evidence of drift term in two-dimensional point vortex system at negative absolute temperature

Yuichi Yatsuyanagi·Tadatsugu Hatori
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Abstract

The drift term appearing in an anaylitically obtained kinetic equation for a point vortex system is evidenced numerically. It is revealed that the local temperature in a region where the vortices are frequently transported by the diffusion and the drift terms characterizes system temperature and its sign is definitely negative. Simulation results clearly show a ransport process of the vortices by the diffusion term (outside the clumps) and the drift term (inside the clumps), which gives a key mechanism of the self-organization, i.e., condensation of the same-sign vortices.

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Yuichi Yatsuyanagi, Tadatsugu Hatori. 2016-11-02. Numerical evidence of drift term in two-dimensional point vortex system at negative absolute temperature. https://arxiv.org/abs/1611.00505

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