The Geospace Environment Modeling (GEM) Program is a broad-based, community-initiated research program on the physics of the Earth's magnetosphere and the coupling of the magnetosphere to the atmosphere and to the solar wind. The work of GEM is accomplished in a series of campaigns and focus groups that solve specific problems leading to the construction of a global Geospace General Circulation Model (GGCM) with predictive capability. This project will contribute essential results to this goal pertaining to understanding the role of plasma waves in energizing and transporting particles and plasma in the near-Earth space environment. In addition, the project supports the research of an early-career tenure-track faculty member and contributes to the research training of another early-career female scientist and a graduate student.
This investigation utilizes both spacecraft observations from THEMIS and Van Allen Probes and the HOTRAY wave ray-tracing computer code to study the modulation of plasma wave intensity by thermal plasma density variations in the inner magnetosphere. The specific science questions to be addressed include: (1) How do thermal plasma density variations cause modulation in the intensity of chorus, hiss and magnetosonic waves? and (2) How do the waves excited by these density variations affect radiation belt and ring current? The investigation is relevant to the GEM Focus Groups on "Storm-Time Inner Magnetosphere-Ionosphere Convection", and "Scientific Magnetic Mapping & Techniques".
