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Solar Cycle Dependence of Mass Density and Ion Composition at Geosynchronous Orbit. Richard E. Denton, Dartmouth Kazue Takahashi, APL Michelle Thomsen, LANL. Solar Cycle Dependence. Mass density. MPA ion density. f10.7. f10.7. Same But Just on Dayside.
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Solar Cycle Dependence of Mass Density and Ion Composition at Geosynchronous Orbit Richard E. Denton, Dartmouth Kazue Takahashi, APL Michelle Thomsen, LANL
Solar Cycle Dependence Mass density MPA ion density f10.7 f10.7
Conclusions • At geosynchronous orbit, the mass density peaks at solar maximum while ion density peaks at solar minimum, the opposite of the expected trend for electron density • This implies a much higher concentration of O+ at solar maximum. • VERY preliminary and not quite right: MPA underestimates ion density by a factor of 4 for O+. Assuming a H+/O+ plasma, we can use the average values at solar max and solar min to find nO+/ne = 0.42 and average ion mass M = 7 at solar max, and nO+/ne = 0.08 and M = 2.2 at solar min.