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arXiv · 2112.11376

A systematic route to subcritical dynamo branches

Paul M. Mannix·Yannick Ponty·Florence Marcotte
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Abstract

We demonstrate that the nonlinear optimisation of a finite-amplitude disturbance over a freely evolving and possibly even turbulent flow, can successfully identify subcritical dynamo branches as well as the structure and amplitude of their critical perturbations. As this approach does not require prior knowledge of the magnetic field amplification mechanisms, it opens a new avenue for systematically probing subcritical dynamo flows.

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Paul M. Mannix, Yannick Ponty, Florence Marcotte. 2021-12-21. A systematic route to subcritical dynamo branches. https://doi.org/10.1103/physrevlett.129.024502

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