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arXiv · 1310.4020

Doppler imaging of the double-lined active binary V824 Ara

Levente Kriskovics·Krisztián Vida·Zsolt Kővári·David Garcia-Alvarez·Katalin Oláh
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Abstract

We introduce an iterative spectral disentangling technique combined with Doppler imaging in order to recover surface temperature maps for both components of double-lined active binary systems. Our method provides an opportunity to separate spectra of the active components while minimizing the unwanted disturbances on the given line profile from the other component. The efficiency of the method is demonstrated on real data of the double-lined RS CVn-type binary V824 Ara. The resulting Doppler images reveal cool spots on the polar regions as well as low-latitude features on both of the stars. Moreover, both components have hot spots, that are facing each other. This may indicate interconnection between the stellar magnetic fields.

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Levente Kriskovics, Krisztián Vida, Zsolt Kővári, David Garcia-Alvarez, Katalin Oláh. 2013-10-15. Doppler imaging of the double-lined active binary V824 Ara. https://doi.org/10.1002/asna.201211974

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