Modelling hybrid stellar pulsators
Asteroseismology is the extension of helioseismology to the study of distant stars. Thanks to the Kepler mission of NASA, the frequencies of oscillations of many thousands of stars have been precisely measured over periods of years. These measurements are enabling a whole new insight into the evolution of stars. Projects focus on the analysis and interpretation of the Kepler data.
Stellar oscillation frequencies probe stellar interiors, informing us about their internal structure, including rotation. In solar-like oscillators, one typically detects frequencies for pressure modes, which are most sensitive to envelope structure. However, gravity modes,mostly sensitive to core structure, have recently been detected in solar-type stars. This project will study how the additional information from the gravity modes helps to constrain stellar model parameters.
In addition, the gravity modes have different sensitivity to known systematic differences caused by inadequate modeling of the near-surface layers, and therefore offer the opportunity to better determine this systematic difference in distant stars.