Planetary Systems around evolved stars provide a unique window regarding the formation and evolution of planetary systems. Almost all planet-host stars will end their lives as white dwarfs, having evolved along the giant branches. By studying planetary systems around giant stars and white dwarfs, we can learn about the key processes that govern their evolution.
Metal lines observed in the atmospheres of white dwarfs, alongside observations of gas and dust, provide evidence for the presence of a planetary system. The best theory to explain these observations suggests that asteroids or comets are perturbed onto star-grazing orbits, following stellar mass loss on the giant branch, before being disrupted and accreted (swallowed) by the white dwarf. Our group works on providing improved theoretical models to explain the processes that occur to the planetary system that lead to the white dwarf observations.