Flux Emergence in the Sunspot Moat

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Session 86 -- Solar Active Regions
Display presentation, Wednesday, 11, 1995, 9:20am - 6:30pm

[86.02] Flux Emergence in the Sunspot Moat

A.M. Title, R.A. Shine, Z.A. Frank (LPARL), G.W. Simon (AFSC/PL/GPSS), P.N. Brandt (Kiepenheuer Institut fuer Sonnenphysik)

On 13-15 June 1994 we obtained simultaneous movies of a sunspot in NOAA active region 7731 through a 3 \AA\ band K line filter, the LPARL tunable filter, and an 8 \AA\ G band filter. The data sets allow us to make aligned magnetic, continuum, Doppler, K line, and G band movies. The sunspot had a well developed moat. Flux emergence occured throughout the moat. The initial signature of the emergence was a transient dark elongated structure in the K line images that was aligned radially with respect to the spot. Bright point pairs appeared at the ends of these features in the K line and G band shortly after their emergence. Magnetic field is observed cospatial with the K line bright point pairs. The magnetic polarity of the end of the pair closest to the spot is the same as the spot. The pairs of bright points move across the moat in a radial direction away from the spot. When the pairs reach the moat boundary the leading bright point merges with a moat feature and the two disappear. The leading bright point's field and the moat field cancel, since the moat boundary and the spot have the same polarity. We believe that these features are different from the long observed moving magnetic features associated with sunspots.

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