Wednesday 27 Feb 2019: [Seminar] Asteroseismology of fast-rotating stars : the contribution of two-dimensional calculations
Dr Giovanni Mirouh - University of Surrey
4th Floor, Physics Building 14:00-15:00
Massive stars directly and indirectly drive the chemical enrichment of the interstellar medium. These stars usually exhibit rapid differential rotation, and are known pulsators. Because of rotation, the oscillation spectra in these stars are hard to interpret and the modes cannot be readily identified, preventing us from using well-established asteroseismology techniques.
In this talk, I will present recent advances in the description of oscillations in such stars. First, I will describe low-frequency oscillations in presence of differential rotation: this rotation affects their propagation and is even responsible for the excitation of some modes. I will then discuss higher-frequency oscillations, that can be split into different categories. Using a convolutional neural network, it was possible to classify these modes automatically and derive a scaling law linking regular patterns in the spectra to stellar properties. Finally, I will suggest future work needed for realistic seismic modelling of fast-rotating stars.