Are granules good tracers of solar surface velocity fields?
نویسندگان
چکیده
منابع مشابه
ASTRONOMY AND ASTROPHYSICS Are granules good tracers of solar surface velocity fields?
Using a numerical simulation of compressible convection with radiative transfer mimicking the solar photosphere, we compare the velocity field derived from granule motions to the actual velocity field of the plasma. We thus test the idea that granules may be used to trace large-scale velocity fields at the sun's surface. Our results show that this is indeed the case provided the scale separatio...
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Aims. Determination of horizontal velocity fields on the solar surface is crucial for understanding the dynamics of structures like mesogranulation or supergranulation or simply the distribution of magnetic fields. Methods. We pursue here the development of a method called CST for coherent structure tracking, which determines the horizontal motion of granules in the field of view. Results. We f...
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Context. The determination of horizontal velocity fields at the solar surface is crucial to understanding the dynamics and magnetism of the convection zone of the sun. These measurements can be done by tracking granules. Aims. Tracking granules from ground-based observations, however, suffers from the Earth’s atmospheric turbulence, which induces image distortion. The focus of this paper is to ...
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ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2001
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361:20011160