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arXiv · 1705.03721

What CoRoT tells us about δ Scuti stars existence of a regular pattern and seismic indices to characterize stars

Eric Michel·Marc-Antoine Dupret·Daniel Reese·Rhita-Maria Ouazzani·Jonas Debosscher·Antonio García Hernández·Kevin Belkacem·Reza Samadi·Sébastien Salmon·Juan Carlos Suarez·Sebastia Barceló Forteza
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Abstract

Inspired by the so appealing example of red giants, where going from a handful of stars to thousands revealed the structure of the eigenspectrum, we inspected a large homogeneous set of around 1860 δ Scuti stars observed with CoRoT. This unique data set reveals a common regular pattern which appears to be in agreement with island modes featured by theoretical non-perturbative treatments of fast rotation. The comparison of these data with models and linear stability calculations suggests that spectra can be fruitfully characterized to first order by a few parameters which might play the role of seismic indices for δ Scuti stars, as {Δν} and {ν_{max}} do for red giants. The existence of this pattern offers an observational support for guiding further theoretical works on fast rotation. It also provides a framework for further investigation of the observational material collected by CoRoT and Kepler. Finally, it sketches out the perspective of using δ Scuti stars pulsations for ensemble asteroseismology.

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Eric Michel, Marc-Antoine Dupret, Daniel Reese, Rhita-Maria Ouazzani, Jonas Debosscher, Antonio García Hernández, Kevin Belkacem, Reza Samadi, Sébastien Salmon, Juan Carlos Suarez, Sebastia Barceló Forteza. 2017-05-10. What CoRoT tells us about δ Scuti stars existence of a regular pattern and seismic indices to characterize stars. https://doi.org/10.1051/epjconf%2F201716003001

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