Solar wind control of the open magnetosphere: Comparison of GGS/polar images and theory.

摘要

This investigation explores the connection between the open polar cap magnetic flux Φ_PCF and interplanetary conditions. Φ _PCF is determined from GGS/Polar VIS Earth Camera far ultraviolet observations of the aurora borealis. Observations from the GGS/Wind SWE and MFI instruments are used to characterize the interplanetary conditions. Additional observations from the IMP-8 PLA and MAG instruments are used to evaluate solar wind propagation time delay estimation methods so that the GGS/Wind observations can be better associated with the GGS/Polar observations. This allows the GGS/Wind observations to be used to estimate the polar cap potential &phis;_PCP values associated with the GGS/Polar Φ_PCF values. Statistical methods are applied to determine a proxy relationship between &phis;_PCP and Φ_PCF. The Rice Field Model (RFM) is modified to accept Φ _PCF as a configuration parameter, and RFM polar caps are produced using Φ _PCF determined both directly from the GGS/Polar images and by the proxy relationship from the GGS/Wind data. The RFM is able to produce polar caps with the same areas and open magnetic fluxes as the GGS/Polar observations, but the agreement in the polar cap shapes and locations leaves opportunities for further improvements.