Physical Society Colloquium
Interview for Faculty Position<
Explosions on the Sun:
Solar flares as cascades of reconnecting magnetic loops
Maya Paczuski
Imperial College
Solar flares are bursts of intense radiation from the corona, caused by the
sudden release of coronal magnetic energy due to reconnection. Robust
power-laws have been observed for the distribution of energy released in
flares, the time intervals between them, etc. suggesting that the corona is
in a self-organized critical state. We introduce a model of the solar coronal
magnetic field where multiple directed loops evolve in space and time. Energy
is fed into the system by the addition of new loops and stirring of
footpoints. When two loops collide they may reconnect, possibly triggering a
cascade of further reconnection. The model reproduces the scaling behavior
for flare statistics as well as some geometrical features of the coronal
magnetic field. We predict that the distribution of net, signed magnetic flux
in grid cells imposed on the photosphere is also power law.
Monday, February 17th 2003, 11:30
Ernest Rutherford Physics Building, R.E. Bell Conference Room (room 103)
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