Solar Winds Triggered By Magnetic Fields
Posted: Mon Nov 02, 2009 11:06 pm
http://www.sciencedaily.com/releases/20 ... 112048.htm
Solar Winds Triggered By Magnetic Fields
ScienceDaily (Nov. 2, 2009) — Solar wind generated by the sun is probably driven by a process involving powerful magnetic fields, according to a new study led by UCL (University College London) researchers based on the latest observations from the Hinode satellite.
. . .
The collaborative study, published in this month's issue of Astrophysical Journal, suggests that a process called slipping reconnection may drive these winds.
. . .
"Solar wind is an outflow of million-degree gas and magnetic field . . . yet we still don't know what drives these outflows.
"However, our latest study suggests that it is the release of energy stored in solar magnetic fields which provides the additional driver for the solar wind. This magnetic energy release is most efficient in the brightest regions of activity on the Sun's surface, called active regions or sunspot groups, which are strong concentrations of magnetic field. We believe that this fundamental process happens everywhere on the Sun on virtually all scales."
Images taken in February 2007 from the EIS instrument showed that hot plasma outflows are due to a process called slipping reconnection. At the edges of active regions where this process can occur, a slow, continuous restructuring of the magnetic field leads to the release of energy and acceleration of particles in the Sun's hot outer atmosphere, known as the corona. Slipping reconnection is the first theory to explain how observed outflows from the Sun can be located over areas of a single magnetic sign, something previously considered improbable.