2019ApJ...874L..23W

We study the nonthermal emission from the interaction between magnetized Jupiter-like exoplanets and the wind from their host star. The supersonic motion of planets through the wind forms a bow shock that accelerates electrons that produce nonthermal radiation across a broad wavelength range. We discuss three wind mass-loss rates: {dot}M_w∼10^–14, 10^–9, 10^–6M_☉yr^–1 corresponding to solar-type, T Tauri, and massive O/B-type stars, respectively. We find that the expected radio synchrotron emission from a Jupiter-like planet is detectable by the Jansky Very Large Array and the Square Kilometre Array at ∼1–10GHz out to a distance of ∼100 pc, whereas the infrared emission is detectable by the James Webb Space Telescope out to a similar distance. Inverse Compton scattering of the stellar radiation results in X-ray emission detectable by Chandra X-ray Observatory out to ∼150 pc. Finally, we apply our model to the upper limit constraints on V380 Tau, the first star-hot Jupiter system observed in radio wavelength. Our bow-shock model provides constraints on the magnetic field, the interplanetary medium, and the nonthermal emission efficiency in V380 Tau.