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arXiv · 1012.0198

Long-term magnetic field monitoring of the Sun-like star Ksi Bootis A

A. Morgenthaler·P. Petit·M. Auriere·B. Dintrans·R. Fares·T. Gastine·J. Lanoux·F. Lignieres·J. Morin·J. Ramirez·S. Saar·S. K. Solanki·S. Theado·V. Van Grootel
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Abstract

Phase-resolved observations of the solar-type star Ksi Bootis A were obtained using the NARVAL spectropolarimeter at the Telescope Bernard Lyot (Pic du Midi, France) during years 2007, 2008, 2009 and 2010. The data sets enable us to study both the rotational modulation and the long-term evolution of various magnetic and activity tracers. Here, we focus on the large-scale photospheric magnetic field (reconstructed by Zeeman-Doppler Imaging), the Zeeman broadening of the FeI 846.84 nm magnetic line, and the chromospheric CaII H and H alpha emission.

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A. Morgenthaler, P. Petit, M. Auriere, B. Dintrans, R. Fares, T. Gastine, J. Lanoux, F. Lignieres, J. Morin, J. Ramirez, S. Saar, S. K. Solanki, S. Theado, V. Van Grootel. 2010-12-01. Long-term magnetic field monitoring of the Sun-like star Ksi Bootis A. https://arxiv.org/abs/1012.0198

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