Some comments on the limb shift of solar lines. II: The effect of granular motions.
Abstract
The well-known correlation between granulation intensity and velocity fluctuations causes a shift of the average line position called the `convective blue shift'. It is argued that this convective blue shift is most likely reponsible for the limb effect of solar Fraunhofer lines. To explain the center-to-limb variation of this limb effect it is essential that both horizontal and vertical motions in the granulation are considered. The effects of a variation in the granulation properties across the Sun on large scale velocity pattern observations are discussed. Abnormal granulation patterns observed inactive regions and at the boundaries of supergranules could be responsible for part or all of the `downflow' observed there.
- Publication:
-
Solar Physics
- Pub Date:
- July 1978
- DOI:
- 10.1007/BF00157270
- Bibcode:
- 1978SoPh...58..243B
- Keywords:
-
- Fraunhofer Lines;
- Frequency Shift;
- Solar Granulation;
- Solar Limb;
- Solar Spectra;
- Convective Flow;
- Doppler Effect;
- Mathematical Models;
- Red Shift;
- Solar Physics;
- Vertical Motion;
- Blue Shift;
- Velocity Fluctuation;
- Scale Velocity;
- Line Position;
- Solar Granulation:Motions;
- Sun: Limb Effect