### Abstract

Original language | English |
---|---|

Pages (from-to) | 177-197 |

Number of pages | 21 |

Journal | Geophysical & Astrophysical Fluid Dynamics |

Volume | 99 |

Issue number | 2 |

DOIs | |

Publication status | Published - 2005 |

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### Keywords

- Magnetohydrodynamics (MHD)
- Magnetic diffusion
- Plasmas
- MHD

### Cite this

*Geophysical & Astrophysical Fluid Dynamics*,

*99*(2), 177-197. https://doi.org/10.1080/03091920500044808

}

*Geophysical & Astrophysical Fluid Dynamics*, vol. 99, no. 2, pp. 177-197. https://doi.org/10.1080/03091920500044808

**Magnetic diffusion and the motion of field lines.** / Wilmot-Smith, A. L.; Priest, E. R.; Hornig, G.

Research output: Contribution to journal › Article

TY - JOUR

T1 - Magnetic diffusion and the motion of field lines

AU - Wilmot-Smith, A. L.

AU - Priest, E. R.

AU - Hornig, G.

N1 - dc.publisher: Taylor & Francis

PY - 2005

Y1 - 2005

N2 - Diffusion of a magnetic field through a plasma is discussed in one-, two- and three-dimensional configurations, together with the possibility of describing such diffusion in terms of a magnetic flux velocity, which, when it exists, is in general non-unique. Physically useful definitions of such a velocity include doing so in terms of the energy flow or in such a way that it vanishes in a steady state. Straight field lines (or plane flux surfaces) diffuse as if flux is disappearing at a neutral sheet, whereas circular field lines (or cylindrical flux surfaces) do so as if flux is disappearing at an 0-type neutral line. In three dimensions it is not always possible to define a flux velocity, for example when the magnetic flux through a closed field line is changing in time. However, in at least some such cases it is possible to describe the behaviour of the magnetic field in terms of a pair of quasi-flux-velocities.

AB - Diffusion of a magnetic field through a plasma is discussed in one-, two- and three-dimensional configurations, together with the possibility of describing such diffusion in terms of a magnetic flux velocity, which, when it exists, is in general non-unique. Physically useful definitions of such a velocity include doing so in terms of the energy flow or in such a way that it vanishes in a steady state. Straight field lines (or plane flux surfaces) diffuse as if flux is disappearing at a neutral sheet, whereas circular field lines (or cylindrical flux surfaces) do so as if flux is disappearing at an 0-type neutral line. In three dimensions it is not always possible to define a flux velocity, for example when the magnetic flux through a closed field line is changing in time. However, in at least some such cases it is possible to describe the behaviour of the magnetic field in terms of a pair of quasi-flux-velocities.

KW - Magnetohydrodynamics (MHD)

KW - Magnetic diffusion

KW - Plasmas

KW - MHD

U2 - 10.1080/03091920500044808

DO - 10.1080/03091920500044808

M3 - Article

VL - 99

SP - 177

EP - 197

JO - Geophysical & Astrophysical Fluid Dynamics

JF - Geophysical & Astrophysical Fluid Dynamics

SN - 0309-1929

IS - 2

ER -