Ring current modeling: Uncommon Assumptions and Common Misconceptions
Abstract:
The dynamics of the ring current involve plasma transport, losses, strong coupling between residing plasma and large scale electric and magnetic fields as well as wave-particle interactions. While in-situ measurements of the inner magnetosphere broaden our understanding of the dynamic processes that dominate this region, the energization of the system remains a difficult issue to examine using observations alone. Consequently, numerical simulations provide an excellent complementary method for investigating the large-scale coupling of the solar wind-ionosphere-magnetosphere system.Despite many years of ring current modeling, which led to qualitative and quantitative progress in the understanding of such complex processes, predicting the creation and demise of the ring current still requires several sets of assumptions, ranging from boundary conditions, composition knowledge to physical limitations of equations sets. Knowledge of these caveats is required in order to avoid misinterpretations of the results.
We present here the outcome from a first ISSI international team meeting, which gathered together experts on this topic to examine these common/known and less common/known facets of ring current modeling. Our overarching goal is to define, classify and systematically assess the validity of the equation set each modeling approach is assuming and to reach an understanding of the common misconceptions in interpreting the results while providing answers to the following questions:
- What are the common/uncommon assumptions we make and should they be revisited?
- What do we know so far from kinetic, MHD, particle tracing, empirical modeling?
- What do model dependent results are teaching us?
- What data sets do we need in order to improve the theoretical representation of the inner magnetosphere currents?