MHD simulations of magnetospheric response to a strong solar wind density pulse

On 16-17 June 2012, an interplanetary coronal mass ejection with an extremely high solar wind density (~100 cm^-3) and mostly strong northward (or eastward) interplanetary magnetic field (IMF) interacted with the Earth’s magnetosphere. We have simulated this event using global MHD models. We study the magnetospheric response to two solar wind discontinuities. The first is characterized by a fast drop of the solar wind dynamic pressure resulting in rapid magnetospheric expansion. The second is a northward IMF turning which causes reconfiguration of the magnetospheric-ionospheric currents. We discuss variations of the magnetopause position and locations of the magnetopause reconnection in response to the solar wind variations. In the second part of our presentation, we present simulation results for the forthcoming SMILE (Solar wind Magnetosphere Ionosphere Link Explorer) mission. SMILE is scheduled for launch in 2024. We produce two-dimensional images that derive from the MHD results of the expected X-ray emission as observed by the SMILE Soft X-ray Imager (SXI). We discuss how SMILE observations may help to study events like the one presented in this work.