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j. Assume externally-driven plasma flow (inputs energy) . Magnetic fields. Magnetic reconnection . A change in magnetic topology in the presence of a plasma. Plasma carrying a current . Jan Egedal, 2007. Magnetic reconnection . A change in magnetic topology
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j Assume externally-driven plasma flow (inputs energy) Magnetic fields Magnetic reconnection • A change in magnetic topology • in the presence of a plasma Plasma carrying a current Jan Egedal, 2007
Magnetic reconnection • A change in magnetic topology • in the presence of a plasma Assume externally-driven plasma flow (inputs energy) Jan Egedal, 2007
Magnetic reconnection • A change in magnetic topology • in the presence of a plasma Assume externally-driven plasma flow (inputs energy) Jan Egedal, 2007
Magnetic reconnection • A change in magnetic topology • in the presence of a plasma Assume externally-driven plasma flow (inputs energy) Jan Egedal, 2007
Magnetic reconnection • A change in magnetic topology • in the presence of a plasma Magnetic configuration now has less energy Nearly all the initial magnetic energy is converted into: 1. thermal energy 2. kinetic energy on fast electrons and ions 3. kinetic energy of large scale flows Jan Egedal, 2007
Magnetic reconnection • A change in magnetic topology • in the presence of a plasma Magnetic configuration now has less energy -Magnetic energy release requires change in magnetic topology: field lines breaking and re-connecting -Reconnection is impossible in a perfectly conducting (very hot) ideal plasma, as plasma current can adjust arbitrarily (Alfvén’s theorem1) 1see e.g. D. Griffiths, Electrodynamics Jan Egedal, 2007