Bibcode
Sobotka, M.; Muller, R.; Bonet, J. A.; Márquez, I.
Bibliographical reference
In: SOLMAG 2002. Proceedings of the Magnetic Coupling of the Solar Atmosphere Euroconference and IAU Colloquium 188, 11 - 15 June 2002, Santorini, Greece. Ed. H. Sawaya-Lacoste. ESA SP-505. Noordwijk, Netherlands: ESA Publications Division, ISBN 92-9092-815-8, 2002, p. 579 - 582
Advertised on:
10
2002
Citations
1
Refereed citations
1
Description
Time series of images of a sunspot, acquired simultaneously in blue
light and in G-band at the SVST, La Palma, are used to study horizontal
motions of granules in the vicinity of the spot and evolution of
penumbral grains (PGs) near the outer penumbral border. Local
correlation tracking and feature tracking algorithms have been utilized
for this purpose. Around sunspots and pores we can observe numerous
centers of diverging local horizontal motions, caused mostly by
exploding granules. Around developed spots we find an organized motion
directed out from the penumbra. The divergence centers are carried away
from the spot by this motion. In the outer penumbra, PGs move mostly
outwards, toward the surrounding granulation. About 2/3 of PGs disappear
near the penumbra-granulation border. The remaining PGs move across the
border, they transform either to granules or to small bright features,
and continue moving away from the sunspot.