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Session 35 - Solar Magnetic Fields.
Display session, Tuesday, June 11
Tripp Commons,

[35.04] High-Resolution Studies of the Solar Polar Magnetic Fields

J. R. Varsik (NSO/SP), P. R. Wilson, Y. Li (Univ. of Sydney)

Most observations of the polar magnetic fields of the Sun have been at relatively low resolution. High-resolution studies of the polar fields offer new insight into their evolution. We show that near sunspot maximum in 1989, the polar regions are covered with several unipolar regions, each region containing magnetic knots of both polarities. These knots have average lifetimes greater than 7 hours but less than 24 hours. In 1995, after the polar field reversal was complete, each pole exhibits one dominant polarity, and the dominant polarity knots are in a ratio of 5:1 to the opposite polarity. By measuring the displacement of magnetic knots over a 7 hour period a rotation rate can be determined which is consistent with the Snodgrass (1982) relation determined by cross correlations of Mt. Wilson magnetograms. Most knots are not seen in magnetic bipoles either when the overall polar fields are mixed or when one polarity is dominant.

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