Arecibo Monitoring Campaign of the Putative Exoplanet-hosting Brown Dwarf TVLM 513-46546

Short-period exoplanets may induce highly beamed electron cyclotron maser radio emission from their host stars via unipolar induction. This mechanism functions in the Jupiter-Io system, which powers some of Jupiter’s auroral activity emitted from UV to radio wavelengths. It provides an indirect means to characterize the magnetism of the orbiting satellite or exoplanet. We present results of a ~10-year campaign to monitor the 4 GHz radio emission from the M9 brown dwarf TVLM 513 465-46 using Arecibo Observatory. This substellar object periodically emits bursty 4-8 GHz radio emission on its P=1.96 hr rotation period, and may host exoplanets that magnetically interact with it. We investigate long-term temporal and luminosity trends in the radio emission, and use them to evaluate hypotheses ranging from inducement via star-planet interactions, to the existence of solar-like magnetic activity cycles.