| 英文摘要: | This grant is for partial support of a project selected and funded under the 2012 NASA-NSF partnership for Space Weather Modeling Collaborations. It is a collaborative effort, led by Princeton University and with participation also from University of New Hampshire, University of California-San Diego, NASA Goddard Space Flight Center, and Los Alamos National Laboratory. The objective is to undertake what amounts to a theoretical and computational grand challenge, namely to develop a state-of-the-art global magnetosphere model that goes beyond the standard framework of the resistive MHD model to include multi-fluid physics, including a generalized Ohms' law, enhanced equations of state for electrons and ions that incorporate kinetic effects, and multiple charged particle species. To this end, the project will assimilate and represent many of the remarkable advances made over the last almost 15 years in our understanding of reconnection, instabilities of current sheets, multiple fluids, and turbulence in collisionless plasmas within the framework of a global magnetosphere code, the OpenGGCM, a traditional version of which is presently used extensively in the community. A suite of mature physics-based modules, based on high-Lundquist-number MHD, Hall MHD, hybrid, multi species, and fully kinetic particle-in-cell codes exist amongst the team members and will be brought together to produce a comprehensive, next-generation global magnetosphere code that will include for the first time extended MHD and kinetic effects.
When completed, the resulting enhanced global magnetosphere model will be delivered to the Community Coordinated Modeling Center (CCMC) for easy and full access to the scientific community and eventual transition to use for operational space weather forecasting. This will enable the accurate modeling of the kinetic scale processes (e.g., magnetic reconnection) responsible for extreme space weather events with direct impact on human society. While the application is geared to the Earth's magnetosphere, the core science module of the model has much broader applicability, and has potentially transformative implications for our ability to understand and predict a broad range of space weather phenomena in the heliosphere that involve magnetic reconnection, instabilities of current sheets, and turbulence. The team, which is a partnership between academia and national laboratories, consists of several junior scientists, postdoctoral fellows, and graduate students who will be educated in this broadly interdisciplinary subject, involving theoretical as well as experimental space plasma physics, applied mathematics, and high-performance computing. |