Overview

Thanks to the space missions CoRoT and Kepler, asteroseismology has successfully probed stellar interiors, especially of solar-like stars and red giants. Such a success has not been achieved yet for non-evolved intermediate-mass and massive stars, as the oscillation spectra of pulsating stars in this mass range exhibit complex patterns that are not well understood. Rapid rotation, a very common feature of these stars, is an identified source of complexity.

Our proposal aims at building a joint effort between modellers and observers, based on existing seismic data for fast rotators, in order to address major difficulties in understanding and studying stars with rapid rotation.

Substantial progress has recently been achieved both in theory and observations. The space missions CoRoT and Kepler have provided seismic data with unprecedented quality for classical pulsators such as δ Scuti stars, γ Doradus or SPB (slow pulsating B-type) stars. It allowed us to accurately determine the frequencies of hundreds of oscillation modes in these stars. The mode identification, i.e. associating each frequency with a mode, is a prerequisite for any further seismic inference. This identification needs theoretical support. In the last years, new theoretical approaches as well as new 2D codes taking into account the centrifugal deformation have been developed to model the internal structure of rotating stars and to compute their oscillation spectra.

We are now close to a convergence between theory and observation. Indeed a first breakthrough has been made with the detection of regular patterns that were predicted by the models.

Our team will gather observers who have analysed CoRoT and Kepler data of classical pulsators, and modellers who have developped new 2D codes and theoretical seismic tools. The team will involve up to 14 researchers, including young scientists, from Belgium, France, Hungary, and Spain.

We aim at providing new seismic diagnosis, especially for stellar rotation so as to obtain new interpretations of CoRoT and Kepler observations of δ Scuti stars, γ Doradus or SPB stars. This work will also help the seismic analyses of future space missions such as TESS and PLATO.

Proposal of the SoFAR Team