Collaborative Research: GEM: Comparative Study of Mars' and Earth's Magnetotail Current Sheets

In collisionless space plasma, mixing and exchanging different energies, e.g., magnetic field energy and charged particle kinetic energy, are controlled by the formation and destruction of plasma structures like current sheets. Current sheets are universal quasi-1D self-consistent plasma and magnetic field configurations that naturally form as boundaries between different plasmas or as current layers embedded within stretched magnetic field lines (typical configuration for the planetary magnetospheres). This project will systematically examine current sheet characteristics in Martian and terrestrial magnetospheres. These two systems differ significantly in plasma content and energies. The team will reveal details of current sheet formation and destruction associated with charged particle acceleration in different parametric regimes. This collaborative project between UTD and UCLA involves significant contributions from two PIs and two graduate students. The configuration and stability of an essential kinetic plasma structure, the current sheet (CS), determine the efficiency of magnetic energy storage, release, and transport in surrounding plasmas. These properties depend on plasma parameters (the ratio of plasma to magnetic field pressures, the ratio of bulk velocities to magnetosonic velocities, etc.). The main scientific goal of this project is to systematically characterize current sheet configurations in the Martian magnetotail (using MAVEN observations), compare these configurations with statistical results of the Earth’s magnetotail current sheets, and reveal the role of plasma parameters, as well as heavy ion contributions, in various configurations. To mitigate the uncertainties due to single-spacecraft measurements from MAVEN, this analysis will be supplemented by comparisons with kinetic simulations of the Martian magnetotail. To compare Martial and Earth’s magnetotail current sheets, we will use current sheet datasets from THEMIS and ARTEMIS, supplemented by Cluster and MMS datasets. 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.