Towards a comprehensive model for planet-disc interaction in 1D models

Since the first detection of an exoplanet orbiting a Sun-like star more than thirty years ago, exoplanet science has advanced at an extraordinary pace. More than 6,000 exoplanets have now been confirmed, and this number is expected to grow rapidly in the coming years. Advances in detection and characterisation techniques, supported by a wide range of ground- and space-based observatories, have greatly expanded our ability to study planets beyond the Solar System.

In parallel, theoretical modelling has progressed dramatically. Modern simulations can now model protoplanetary discs on global scales while including radiation and magnetic fields. Yet a fundamental challenge remains: planet formation itself is rarely observable directly. Constraining formation models therefore requires large ensembles of simulations whose outcomes can be compared statistically with the observed exoplanet population. Owing to their low computational cost, 1D models remain the preferred tool for such studies.

This computational efficiency, however, comes at the cost of physical simplifications, particularly in the treatment of planet–disc interactions. Existing models often rely on simplified prescriptions for orbital migration and gap formation, especially in multi-planet systems. These approximations can significantly affect predictions for planetary masses and orbital distributions.

Here, we present a novel framework for modelling planet–disc interactions in 1D simulations. Our approach includes a detailed treatment of angular momentum exchange between planets and the disc and accurately reproduces gap structures seen in hydrodynamic simulations.