GEM: Turbulence and Structure in the Magnetospheric Cusps: Cluster Spacecraft Observations and Numerical Simulations

Embry-Riddle Aeronautical University, Daytona Beach FL

Investigators

Abstract

The primary goal of this project is to understand the formation of structure, boundaries and low frequency turbulence in the high-altitude cusp and to study particle acceleration due to the motion of the structures, magnetic reconnection and low frequency turbulence. The investigation will use several years of Cluster satellite data complemented with Double Star satellite data in the magnetosheath. Data analysis methods include variance analysis techniques, transforming observations into the deHoffman Teller frame of reference, use of the Walen relation, multi-spacecraft methods, and spectral analysis methods such as Fast Fourier Transform and Wavelet analysis. The data analysis results will be compared with three-dimensional high-resolution MHD simulations in the cusp geometry. Virtual spacecraft measurements can be taken in the simulation box and compared with satellite data. The simulations will also use test particles. The study will address several specific topics: (1) The formation of diamagnetic cavities and other boundaries in the cusp, (2) the role of Kelvin-Helmholtz modes and reconnection as generators of low frequency turbulence in the cusp, (3) the effect of sheath turbulence on cusp turbulence, and (4) the effect of (i) the motion of the diamagnetic cavities, (ii) reconnection, and (iii) low frequency wave turbulence on particle acceleration in the cusp. The project integrates research and education by including undergraduate students of Embry-Riddle Aeronautical University (ERAU) in a summer research program. The PI will also generate a project website that makes it easy and interesting for the undergraduate students in ERAU (but also for a broader audience) to get familiar with the project and learn space science through it. The ERAU is promoting equal opportunities for the underrepresented groups and the PI will follow this tradition when nominating students for this project.