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arXiv · 2311.08831

Introduction to Field Line Helicity

A. R. Yeates·M. A. Berger
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Abstract

Field line helicity measures the net linking of magnetic flux with a single magnetic field line. It offers a finer topological description than the usual global magnetic helicity integral, while still being invariant in an ideal evolution unless there is a flux of helicity through the domain boundary. In this chapter, we explore how to appropriately define field line helicity in different volumes in a way that preserves a meaningful topological interpretation. We also review the time evolution of field line helicity under both boundary motions and magnetic reconnection.

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A. R. Yeates, M. A. Berger. 2023-11-15. Introduction to Field Line Helicity. https://arxiv.org/abs/2311.08831

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