Spectral properties of SWCX emission from the Earth's outer boundaries

Transfers of energy and momentum through the Sun–Earth system, including during geomagnetic storms, alter the fundamental state of the magnetosphere. However, previous observations have been limited by the restricted and often single-point nature of in-situ satellite measurements and ground-based observations. The Solar Wind Charge Exchange (SWCX) mechanism, where X-ray emissions are generated through interactions between heavy, highly charged solar wind ions and neutral atoms, offers new opportunities to observe the magnetosphere in a more dynamic and spatially resolved way.

In the presentation, we showcase results that model and analyze SWCX signatures from Earth’s magnetopause and cusp regions using global Magnetohydrodynamics (MHD) simulations enhanced to incorporate heavy ions and X-ray emissions. We also present comparisons between predictions from the global MHD model and those from our embedded kinetic test-particle model. The SWCX mechanism is highly species dependent, governed by interaction cross sections and solar wind ion abundances. Our simulations capture these species-specific properties, producing X-ray emission spectra with species-level resolution.

These emission profiles help us study solar wind drivers, their spatial and temporal evolution, and their ability to distinguish key magnetospheric regions. These findings are highly relevant, for upcoming missions such as SMILE (Solar wind Magnetosphere-Ionosphere Link Explorer), the first mission dedicated to observing global X-ray emissions from Earth’s magnetosphere. The model also enables investigation of kinetic particle effects such as Kelvin–Helmholtz waves and Flux Transfer Events (FTEs), which are discussed further.