Miguel T. Clara
IA / FCUP

Abstract
Grid-based modelling techniques have been shown to enable the determination of stellar properties with significant accuracy, justifying their use in the context of data exploitation from space missions like Kepler, TESS or PLATO.
Subgiants are particularly interesting and challenging in the asteroseismic context, as changes in their physical and chemical structure allow the emergence of mixed modes, asteroseismic features that can potentially allow the determination of stellar properties with great precision. However, current stellar grids lack the necessary resolution to properly account for the fast mode frequency evolution, and require interpolation methods to cover the parameter space in between the grid models when applying model-data comparison methods. The errors resulting from the interpolation of non-radial modes across different masses in a typical grid of subgiant models can be as high as a few tens of muHz (up to 2 orders of magnitude higher than the observational errors in some stars).
In this talk, I intend to explore the importance of subgiants in the characterization of stars through asteroseismology, as well as to characterize the problem of frequency interpolation in the subgiant phase, and explore several possibilities to improve on the current procedures.

2023 June 06, 13:30

IA/U.Porto
Centro de Astrofísica da Universidade do Porto (Auditorium)
Rua das Estrelas, 4150-762 Porto