Bibcode
DOI
Vargas Domínguez, S.; Bonet, J. A.; Martínez Pillet, V.; Katsukawa, Y.; Kitakoshi, Y.; Rouppe van der Voort, L.
Bibliographical reference
The Astrophysical Journal, Volume 660, Issue 2, pp. L165-L168.
Advertised on:
5
2007
Journal
Citations
27
Refereed citations
25
Description
Proper motions in a sunspot group with a δ-configuration and close
to the solar disk center have been studied by employing local
correlation tracking techniques. The analysis is based on a more than 1
hr time series of G-band images. Radial outflows with a mean speed of
0.67 km s-1 have been detected around the spots, the
well-known sunspots moats. However, these outflows are not found in
those umbral core sides without penumbra. Moreover, moat flows are only
found in those sides of penumbrae located in the direction marked by the
penumbral filaments. Penumbral sides perpendicular to them show no moat
flow. These results strongly suggest a relation between the moat flow
and the well-known, filament-aligned Evershed flow. The standard picture
of a moat flow originating from a blocking of the upward propagation of
heat is discussed in some detail.