May Gade Pedersen

Probing time dependent convective boundary mixing with gravity mode oscillations

One of the dominant uncertainties in the evolution of stars with convective cores arises from their poorly constrained internal mixing properties. Such mixing can renew the hydrogen fuel in the stellar cores, thereby significantly extending their main-sequence lifetimes and increasing the final helium core mass obtained at core hydrogen exhaustion. Different mixing processes occurring near the convective boundaries are collectively referred to as convective boundary mixing (CBM). Their implementation in 1D stellar structure and evolution codes generally rely on at least one free parameter that defines the extent and mixing efficiency in this region. One such type of CBM is convective penetration. Recently, 3D numerical simulations of convective penetration occurring at the boundary of convective cores suggest that the extent of this CBM region can be directly computed from the properties of the core and changes size as the star evolves. Here we investigate if gravity mode oscillations, which have the highest probing power near the convective core, are sensitive to such time dependent CBM and if such mixing is sufficient to explain the gravity mode oscillations observed in Slowly Pulsating B stars.