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arXiv · 0801.4724

Links between magnetic fields and plasma flows in a coronal hole

T. Wiegelmann·L. D. Xia·E. Marsch
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Abstract

We compare the small-scale features visible in the Ne viii Doppler-shift map of an equatorial coronal hole (CH) as observed by SUMER with the small-scale structures of the magnetic field as constructed from a simultaneous photospheric magnetogram by a potential magnetic-field extrapolation. The combined data set is analysed with respect to the small-scale flows of coronal matter, which means that the Ne viii Doppler-shift used as tracer of the plasma flow is investigated in close connection with the ambient magnetic field. Some small closed-field regions in this largely open CH are also found in the coronal volume considered. The Doppler-shift patterns are found to be clearly linked with the field topology.

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T. Wiegelmann, L. D. Xia, E. Marsch. 2008-01-30. Links between magnetic fields and plasma flows in a coronal hole. https://doi.org/10.1051/0004-6361:200500029

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