Oral Abstract

Oral Contribution (O0.8) Harish Vedantham (ASTRON)

Opening the radio window to exoplanets and brown dwarfs

Magnetic fields dominate the dynamics of plasma in the atmospheres of brown dwarfs and exoplanets. As such, they influence the escape of atmospheric gases and some key chemical reactions. Observations of exoplanets' cyclotron emission, that falls in the radio band, is a promising technique to measure their magnetic fields. However, the previous generation of radio telescopes was not sensitive enough to detect the coldest brown dwarfs and exoplanets, particularly at low radio frequencies (< 1 GHz) where their cyclotron emission is anticipated. In this talk, I will present recent LOFAR discoveries to demonstrate that radio observations of the coldest brown dwarfs are now within reach. I will discuss prospects to use such radio observations to (a) test magnetic dynamo models that predict exoplanetary magnetic field strengths and (b) to discover exoplanets around brown dwarfs and exo-moons around gas-giant exoplanets.