Simulated Coronal EUV Emission from Exoplanet Host Stars

We apply a modified solar flux transport (SFT) model, developed by Schrijver and colleagues, to emulate the magnetic activity of the host stars of recently discovered habitable-zone planets. The magnetic flux distributions produced by the SFT simulations serve as a first-order proxy for the expected magnetic behavior of an exoplanet host star. We couple the simulated magnetic structure to a coronal heating model and simulate the expected EUV and X-ray emission of the target star. The EUV emission is a key energetic input to the exoplanetary atmosphere, governing ionospheric conductance and therefore influencing the magnetospheric response to stellar activity – a key factor in determining the overall atmospheric loss and ultimately the potential of the planet for habitation. In addition, the simulated stellar coronal emission may provide signatures for comparison with astronomical observations. We consider the simulated activity over a number of stellar cycles to explore the long-term impact of the star on the exo-planetary environment.