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arXiv · 0809.4222

Modeling X-ray emission from stellar coronae

S. G. Gregory·M. Jardine·C. Argiroffi·J. -F. Donati
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Abstract

By extrapolating from observationally derived surface magnetograms of low-mass stars we construct models of their coronal magnetic fields and compare the 3D field geometry with axial multipoles. AB Dor, which has a radiative core, has a very complex field, whereas V374 Peg, which is completely convective, has a simple dipolar field. We calculate global X-ray emission measures assuming that the plasma trapped along the coronal loops is in hydrostatic equilibrium and compare the differences between assuming isothermal coronae, or by considering a loop temperature profiles. Our preliminary results suggest that the non-isothermal model works well for the complex field of AB Dor, but not for the simple field of V374 Peg.

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S. G. Gregory, M. Jardine, C. Argiroffi, J. -F. Donati. 2008-09-24. Modeling X-ray emission from stellar coronae. https://doi.org/10.1063/1.3099184

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