Séminaires

Characterising the rotation of solar-type stars in the PLATO era
Sylvain Breton (INAF Catania)

Salle de réunion AGO (local -1/14), Institut d'Astrophysique et de Géophysique
Bâtiment B5c, Quartier Agora, Allée du 6 Août, 19C, B-4000 Liège 1 (Sart-Tilman)

Setting constraints on the rotation profile of solar-type stars is a fundamental problem to characterise the way they evolve and interact with their environment. The advent of space photometry (CoRoT, Kepler/K2, TESS) was instrumental in bringing us insights on the rotational dynamics of large samples of solar-type stars. With its unmatched photometric capabilities, the upcoming PLATO mission promises to take us several steps further in the perspective of building a coherent view of stellar internal angular momentum transport and rotational evolution.

In this seminar, I will start by presenting the strategy that PLATO will use to measure surface rotation and activity from the analysis of photospheric brightness modulations connected to the transit of active regions in the visible disk. I will explain the possible synergies between these measurements and the acoustic mode asteroseismology that the high cadence of PLATO light curves will also enable. I will then emphasise how we lack observational constraints on the deep dynamics of solar-type stars during their journey on the main sequence. In consequence, I will describe how studying low-frequency stellar oscillations in the non-linear context of 3D simulations might represent the way forward to guide the analysis of photometric observations. In particular, I will present the first simulations of a 1.3 Msun star including both the convective core and envelope surrounding the radiative interior, and I will comment on the consequences that this coupling has on the behaviour of the internal gravity waves excited by the stochastic convective motions.