Poster
I. M. Rolo, M. S. Cunha, D. L. Holdsworth, A. R. G. Santos
Abstract
The study of chemically peculiar (CP) stars has the potential to revolutionise our
current understanding of processes at play inside all stars. Specifically, pulsating CP stars are
perfect laboratories for studying stellar physics, as asteroseismology provides robust
observational constraints. As a first step towards comprehending the intricacies of these stars,
in this work, we focus on a particular group of pulsating CP stars: the rapidly oscillating
chemically peculiar A-type (roAp) stars. So far, conducting studies of roAp stars has been
especially difficult due to the rarity of these objects. However, the large-scale TESS and Gaia
surveys have truly expanded our horizons, allowing for the collection of data for ~100 roAp
stars. We homogeneously determine seismic and non-seismic parameters of these stars and
analyse them using a plethora of methods, to be showcased here. We find evidence for the
existence of two different populations in the data when closely inspecting the radial order of
these stars. Comparing the results with state-of-the-art theoretical stellar models, we conclude
that one of these populations cannot be explained by the models. Going forward, this finding will
contribute to further development of stellar models, and ultimately improve our understanding of
the mechanisms that drive the pulsations in roAp stars.
8th TESS/15th Kepler Asteroseismic Science Consortium Workshop
Porto, Portugal
2024 July
