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Towards age/rotation/magnetic activity relation with seismology
The knowledge of stellar ages directly impacts the characterization of a
planetary system as it puts strong constraints on the moment when the system
was born. Unfortunately, the determination of precise stellar ages is a very
difficult task. Different methods can be used to do so (based on isochrones or
chemical element abundances) but they usually provide large uncertainties.
During its evolution a star goes through processes leading to loss of angular
momentum but also changes in its magnetic activity. Building rotation,
magnetic, age relations would be an asset to infer stellar ages model
independently. Several attempts to build empirical relations between rotation
and age (namely gyrochronology) were made with a focus on cluster stars where
the age determination is easier and for young stars on the main sequence. For
field stars, we can now take advantage of high-precision photometric
observations where we can perform asteroseismic analyses to improve the
accuracy of stellar ages. Furthermore, the variability in the light curves
allow us to put strong constraints on the stellar rotation and magnetic
activity. By combining these precise measurements, we are on the way of
understanding and improving relations between magnetic activity, rotation, and
age, in particular at different stages of stellar evolution. I will review the
status on gyrochronology relationships based on observations of young cluster
stars. Then I will focus on solar-like stars and describe the inferences on
stellar ages, rotation, and magnetism that can be provided by high-quality
photometric observations such as the ones of the Kepler mission, in particular
through asteroseismic analyses.Comment: 6 pages, 3 figures. Proceedings of the CoRoT3-KASC7 conference: The
Space Photometry Revolutio
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