# Relative field-line helicity in bounded domains

@article{Yeates2018RelativeFH, title={Relative field-line helicity in bounded domains}, author={Anthony R. Yeates and Marcus Page}, journal={Journal of Plasma Physics}, year={2018}, volume={84} }

Models for astrophysical plasmas often have magnetic field lines that leave the boundary rather than closing within the computational domain. Thus, the relative magnetic helicity is frequently used in place of the usual magnetic helicity, so as to restore gauge invariance. We show how to decompose the relative helicity into a relative field-line helicity that is an ideal-magnetohydrodynamic invariant for each individual magnetic field line, and vanishes along any field line where the original…

## 9 Citations

### Relative magnetic field line helicity

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Solar ﬂares and coronal mass ejections are the largest energy release phenomena in the current solar system. They cause drastic enhancements of electromagnetic waves of various wavelengths and…

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Coronal mass ejections (CMEs) – among the most energetic events originating from the Sun – can cause significant and sudden disruption to the magnetic and particulate environment of the heliosphere.…

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During solar minimum, the Sun is relatively inactive with few sunspots observed on the solar surface. Consequently, we observe a smaller number of highly energetic events such as solar flares or…

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