Ion Heating in the Solar Wind and Corona

Space weather is a major cause of satellite degradation and failure, causing severe economic impacts not only within the space industry but also downstream users including agricultural and transportation industries. This project will develop rigorous, physics-based models of the Sun's corona and solar wind, a stream of energetic particles from the Sun, that causes mild to extreme space weather on Earth and affects satellites and critical space infrastructure. The models will add to our pool of knowledge and improve strategic capabilities in space weather forecasting. This project also has profound implications for our understanding of the wider universe: the same physics is essential for interpretation of new astrophysical data. Finally, this work will train undergraduate students in the fundamental plasma physics techniques and models needed not just in space sciences and industry, but also in the rapidly growing commercial fusion power sector. Ion heating is essential to explain the heating of the corona and the acceleration of the solar wind. One attractive model for how the heating occurs is via plasma turbulence: chaotic fluctuations in the coronal plasma over a wide range of scales. However, significant challenges remain when it comes to quantitative modelling of this process. This project uses a new model that takes into account the intermittent, random fluctuations in the turbulence, essential for accurate heating determinations, and will use a novel, sensitive observational technique to diagnose the heating directly from spacecraft data. By combining state-of-the-art observations and theoretical modelling, this work will significantly advance our understanding of heating across a wide range of conditions in the corona and solar wind. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.