SHINE: Theoretical Investigation of Small Scale Structure in Solar Flare Current Sheets

点击翻译按钮获取中文摘要

Magnetic reconnection is a fundamental physical space plasma process that is the driver of solar eruptions. A detailed understanding of magnetic reconnection, therefore, is an important component of understanding the physical processes responsible for space weather at Earth. Magnetic reconnection governs the dynamics and heating of other astrophysical plasmas as well. The process occurs on length scales much shorter than can be observed remotely, but the released energy and changes in magnetic structure have important global consequences. The objective of this project is to perform numerical simulations of magnetic reconnection in the solar atmosphere that result in predictions that are suitable for comparison with solar observations. The results will provide new understanding of the observational signatures of reconnection and new understanding of the role of small-scale structures in rapid reconnection and particle acceleration. The project includes significant science education and public outreach components. Members of the proposal team will mentor undergraduate summer interns. Funding is also included to coordinate outreach efforts by solar physicists for a local science festival. Each year, this festival brings in hundreds of members of the public of all ages, with exhibits designed to be informative to everyone in attendanceThis research project is aimed at characterizing the small-scale structure in density, temperature, and energy within the reconnection region, which is vital for the dynamics of reconnection and particle acceleration. If strong variations in temperature or density exist, then this will substantially impact the ionization evolution and consequently the interpretation of observations. Both two-dimensional and three-dimensional simulations will be performed, with a focus on investigating how the tearing and plasmoid instabilities drive turbulence and enhance reconnection rates. The statistical properties of the nonlinear dynamics resulting from these instabilities will be investigated to provide insight into particle acceleration and the dynamics of reconnection. While most observations of solar eruptions are interpreted under the assumption that the plasma is in ionization equilibrium, the time scales for ionization and recombination are often comparable to or longer than the time scales of the eruption. The observational predictions will therefore be made using time-dependent ionization modeling in the post processing, including the effects of non-thermal particle distributions.