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Photospheric and chromospheric activity in four young solar-type stars

Katia Biazzo·Antonio Frasca·Gregory W. Henry·Santo Catalano·Ettore Marilli
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Abstract

We present a photometric and spectroscopic study of four G-K dwarfs, namely HD 166, epsilon Eri, chi1 Ori and kappa1 Cet. In three cases, we find a clear spatial association between photospheric and chromospheric active regions. For chi1 Ori we do not find appreciable variations of photospheric temperature, and chromospheric Halpha emission. We applied a spot/plage model to the observed rotational modulation of temperature and flux to derive spot/plage parameters and to reconstruct a rough three-dimensional map of the outer atmosphere of kappa1 Cet, HD 166 and epsilon Eri.

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Katia Biazzo, Antonio Frasca, Gregory W. Henry, Santo Catalano, Ettore Marilli. 2006-09-19. Photospheric and chromospheric activity in four young solar-type stars. https://doi.org/10.1086/510279

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