Infrared interferometric characterisation of second generation protoplanetary discs

In a binary star system, one of the stars is further in the evolutionary phase than the other one. At the point of investigation, one of the stars has gone through the red giant star phase. At the end of their life some binary stars form Keplerian discs of gas and dust with similar properties to planet-forming discs around young stars (protoplanetary discs). Around evolved binaries, these scaled-up versions of discs, called the second generation protoplanetary discs because of their resemblence to first generation protoplanetary discs, form as the result of an unconstrained binary interaction process taking place at the end of the asymptotic giant branch evolution of the initially most massive star. Dynamical interactions between the binary and its circumbinary disc strongly influence the evolution of these objects. However, these interactions are poorly constrained and the disc's structure, dispersal and evolution remain elusive. With this project we focus on the very inner structure and aim at spatially resolving all building blocks of these systems and their interactions. We will use a combination of observational data as well as state-of-the art radiative transfer modelling tools. This project is embedded into a larger research project for which we recently obtained a large programme of observations, called “INSPIRING”, at ESO/VLTI.