Science goals and objectives we propose to investigate and contrast the effects of stochastic (diffusive) transport processes with transport resulting from coherent interactions of energetic particles…

This is a research grant awarded by the National Aeronautics and Space Administration (NASA) to the Regents of the University of Colorado, doing business as the University of Colorado Office of Contracts and Grants Division. The $906,946.01 grant, awarded on September 12, 2017, is for investigating the effects of stochastic (diffusive) transport processes versus coherent interactions of energetic particles with large-scale magnetospheric disturbances. The research aims to expand scientific understanding of the dynamics of energetic particles in the inner magnetosphere. The grant does not have a set-aside designation and is scheduled for completion on February 16, 2023. As a public research university, the University of Colorado has extensive expertise in space physics, climate science, and other science, technology, engineering, and mathematics (STEM) disciplines, and has received past federal research grants and contracts from agencies like NASA, the Department of Defense, and NOAA.

Science goals and objectives we propose to investigate and contrast the effects of stochastic (diffusive) transport processes with transport resulting from coherent interactions of energetic particles with large scale magnetospheric disturbances. Processes affecting the dynamics of energetic particles in the inner magnetosphere may be broadly categorized as either stochastic processes, describing individually-random dynamics of an ensemble of particles interacting with a spectrum of magnetospheric waves; or coherent processes, whereby the dynamics of the particles are collectively driven in one direction in energy or space. On timescales longer than the drift period stochastic processes lead to radial diffusion, whereby particles move randomly through regions of higher or lower magnetic field strength, gaining or losing energy in accordance with the conservation of the particle's magnetic moment. The radial profile of phase space density determines whether a net increase in energy occurs resulting from a positive outward gradient or a net loss of energy from a negative gradient. Coherent processes, by contrast, result from interactions with convective or impulsive transfers of energy with a well-defined direction. Examples of key coherent processes in the inner magnetosphere include plasmasheet injections into the stable trapping region during substo MS, and injections of previously-trapped particles from high l values during impulsive events induced by shocks in the solar wind.