Hunting for exoplanets via star-planet interactions

Low-mass stars host the bulk of all exoplanets in our galaxy. While the population of exoplanets discovered to date is dominated by those that are close-in, massive, and transit, such a population is not representative of the complete sample. M dwarfs, which are the most common type of star in the galaxy, are expected to favour hosting small rocky planets. Finding such planets however is very difficult through traditional methods, as their signatures are very weak, and can be drowned out by stellar activity. M dwarfs also harbour strong surface magnetic fields, which dominate the energetics of the surrounding plasma environment out to large distances. In this region, the motion of a planet through the star's large-scale magnetic field can produce Alfvén waves, which carry energy back to the star. Such a scenario is expected to power bright radio emission from the star via the electron cyclotron maser (ECM) instability. Due to the beamed nature of ECM emission, such signatures could be more favourable for detection from exoplanetary systems with architectures distinct from the currently known population. Here, I present our recent work utilising numerical models to identify the most favourable systems for detecting these signatures based on the characteristics of the star and planetary orbit.