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Using Gaia to measure the atmospheric dynamics in AGB stars

Published online by Cambridge University Press:  30 December 2019

Andrea Chiavassa ,
Bernd Freytag  and
Mathias Schultheis
Andrea Chiavassa
Affiliation:
Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Lagrange, CS 34229, Nice, France email: andrea.chiavassa@oca.eu
Bernd Freytag
Affiliation:
Department of Physics and Astronomy at Uppsala University, Regementsvägen 1, Box 516, SE-75120 Uppsala, Sweden
Mathias Schultheis
Affiliation:
Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Lagrange, CS 34229, Nice, France email: andrea.chiavassa@oca.eu
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Abstract

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We use 3D radiative-hydrodynamics simulations of convection with CO5BOLD and the post-processing radiative transfer code Optim3D to compute intensity maps in the Gaia G band [325–1030 nm]. We calculate the intensity-weighted mean of all emitting points tiling the visible stellar surface (i.e., the photo-center) and evaluate its motion as a function of time. We show that the convection-related variability accounts for a substantial part to the Gaia DR2 parallax error of our sample of semiregular variables. Finally, we denote that Gaia parallax variations could be exploited quantitatively to extract stellar parameters using appropriate RHD simulations corresponding to the observed star.

Keywords

stars: atmospheresstars: AGBastrometryparallaxeshydrodynamics
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 14 , Symposium S343: Why Galaxies Care About AGB Stars: A Continuing Challenge through Cosmic Time , August 2018 , pp. 373 - 374
Copyright
© International Astronomical Union 2019 

References

Arenou, F., Luri, X., Babusiaux, C., et al. 2018, arXiv:1804.09375Google Scholar
Chiavassa, A., Plez, B., Josselin, E., & Freytag, B. 2009, A&A, 506, 1351 CrossRefGoogle Scholar
Chiavassa, A., Freytag, B., & Schultheis, M. 2018, arXiv:1808.02548Google Scholar
Evans, D. W., Riello, M., De Angeli, F., et al. 2018, arXiv:1804.09368Google Scholar
Freytag, B., Steffen, M., Ludwig, H.-G., et al. 2012, Journal of Computational Physics, 231, 919 CrossRefGoogle Scholar
Freytag, B., Liljegren, S., & Höfner, S. 2017, A&A, 600, A137 CrossRefGoogle Scholar
Glass, I. S., & van Leeuwen, F. 2007, MNRAS, 378, 1543 CrossRefGoogle Scholar
Jura, M., Yamamoto, A., & Kleinmann, S. G. 1993, ApJ, 413, 298 CrossRefGoogle Scholar
Mowlavi, N., Lecoeur-Taïbi, I., Lebzelter, T., et al. 2018, arXiv:1805.02035Google Scholar
Tabur, V., Bedding, T. R., Kiss, L. L., et al. 2009, MNRAS, 400, 1945 CrossRefGoogle Scholar