Divergence and Vorticity at Solar Mesogranular Scales
Abstract
Ten time series of solar granulation filtergrams at high spatial resolution and various durations, i. e. from 20 min to several hours, (one data set is from numerical simulations) are used to investigate the relation between vorticity and divergence at mesogranular scales. Velocity fields at various scales were generated by local correlation tracking and from these divergence and vorticity were computed. In all data sets we find a strong preference of stronger vortices at downflowing regions, i.e. where the divergence is negative. This holds especially for scales larger than granular sizes and for longer lifetimes.
- Publication:
-
Central European Astrophysical Bulletin
- Pub Date:
- 2007
- Bibcode:
- 2007CEAB...31...11P
- Keywords:
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- granulation;
- mesogranulation;
- vorticity;
- divergence