## Abstract

The magnetic breakout model gives an elegant explanation for the onset of an eruptive solar flare, involving magnetic reconnection at a coronal null point which leads to the initially enclosed flux 'breaking out' to large distances. In this paper we take a topological approach to the study of the conditions required for this breakout phenomenon to occur. The evolution of a simple delta sunspot model, up to the point of breakout, is analysed through several sequences of potential and linear force-free quasi-static equilibria. We show that any new class of field lines, such as those connecting to large distances, must be created through a global topological bifurcation and derive rules to predict the topological reconfiguration due to various types of bifurcation.

Original language | English |
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Pages (from-to) | 2099-2120 |

Number of pages | 22 |

Journal | Proceedings of the Royal Society A - Mathematical, Physical & Engineering Sciences |

Volume | 461 |

Issue number | 2059 |

DOIs | |

Publication status | Published - 8 Jul 2005 |

## Keywords

- solar flare
- magnetic breakout
- magnetic topology
- solar corona.
- 3-DIMENSIONAL NULL POINTS
- CORONAL MASS EJECTIONS
- FORCE-FREE
- CURRENT SHEETS
- FLUX EMERGENCE
- FIELDS
- RECONNECTION
- EVOLUTION
- FEATURES
- COMPLEX