Solar Wind Correlations: Using a Solar Wind Monitor Successfully

Abstract

Solar wind plasma correlations between data from three spacecraft — IMP 8, INTERBALL-1, and WIND — are analyzed for periods near the most recent solar minimum. There are two primary foci of this study: 1) to understand the physics underlying good and poor correlation periods, and 2) to investigate and quantify the degree to which distant solar wind plasma measurements (such as those from near Earth’s L1 point) represent the solar wind affecting the magnetosheath and magnetosphere.

The correlations are examined as a function of the positional separations (in GSE) of the spacecraft, the average flux, speed, and density of the solar wind, the standard deviations of those parameters, and the lags that give the maximum correlation. The character of the correlation behavior (i.e., what percentage of the time good or poor correlations are observed) appears to be dependent on X-separation past some distance (~ 220 R _E )which may be dependent on solar cycle timing. There appear to be no strong dependencies on Y-separation or on speed, but some dependence on the flux and density magnitudes and the dependence on their standard deviations is especially strong.