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arXiv · 1011.4299

Plasmoid ejections driven by dynamo action underneath a spherical surface

Jörn Warnecke·Axel Brandenburg·Dhrubaditya Mitra
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Abstract

We present a unified three-dimensional model of the convection zone and upper atmosphere of the Sun in spherical geometry. In this model, magnetic fields, generated by a helically forced dynamo in the convection zone, emerge without the assistance of magnetic buoyancy. We use an isothermal equation of state with gravity and density stratification. Recurrent plasmoid ejections, which rise through the outer atmosphere, is observed. In addition, the current helicity of the small--scale field is transported outwards and form large structures like magnetic clouds.

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Jörn Warnecke, Axel Brandenburg, Dhrubaditya Mitra. 2010-11-18. Plasmoid ejections driven by dynamo action underneath a spherical surface. https://doi.org/10.1017/s1743921311007186

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