Widespread Occurrence of Trenching Patterns in the Granulation Field: Evidence for Roll Convection?

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

16 pages, 7 figures; accepted by Solar Physics

Scientific paper

10.1007/s11207-007-9056-9

Time-averaged series of granulation images are analysed using COLIBRI, a purpose-adapted version of a code originally developed to detect straight or curvilinear features in aerospace images. The algorithm of image processing utilises a nonparametric statistical criterion that identifies a straight-line segment as a linear feature (lineament) if the photospheric brightness at a certain distance from this line is on both sides stochastically lower or higher than at the line itself. Curvilinear features can be detected as chains of lineaments, using a criterion modified in some way. Once the input parameters used by the algorithm are properly adjusted, the algorithm highlights ``ridges'' and ``trenches'' in the relief of the brightness field, drawing white and dark lanes. The most remarkable property of the trenching patterns is a nearly-universally-present parallelism of ridges and trenches. Since the material upflows are brighter than the downflows, the alternating parallel light and dark lanes should reflect the presence of roll convection in the subphotospheric layers. If the numerous images processed by us are representative, the patterns revealed suggest a widespread occurrence of roll convection in the outer solar convection zone. In particular, the roll systems could form the fine structure of larger-scale, supergranular and/or mesogranular convection flows. Granules appear to be overheated blobs of material that could develop in convection rolls due to some instabilities of roll motion.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Widespread Occurrence of Trenching Patterns in the Granulation Field: Evidence for Roll Convection? does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Widespread Occurrence of Trenching Patterns in the Granulation Field: Evidence for Roll Convection?, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Widespread Occurrence of Trenching Patterns in the Granulation Field: Evidence for Roll Convection? will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-518189

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.