Testing for Planetary Modulation of YZ Ceti's Radio Bursts

Based on the Jupiter-Io system, magnetic star-planet interaction (SPI) is predicted to cause luminous stellar radio bursts, whose luminosity depends on the exoplanet's magnetic field strength. A few radio SPI candidates have been reported, based on detections of radio bursts from stars known or suspected to host a sub-Alfvénic planet. However, no candidate system yet has confirmed orbital modulation of the radio burst timing, which is necessary to determine whether the radio bursts are stochastic stellar activity or truly SPI. We will present results from a 50-hour, 1-2 GHz monitoring program of SPI candidate system YZ Ceti, an M4 dwarf with a 2-day-orbit terrestrial planet, which seeks to explain why this slowly rotating star emits relatively frequent radio bursts. This program will compare the burst rate "in phase", at an orbital phase range where radio bursts were previously detected, to "out of phase" at randomly sampled times.