Correlation Between the Magnetic Field and Plasma Parameters at 1 AU

Zicai Yang   Fang Shen   Jie Zhang   Yi Yang   Xueshang Feng   Ian G. Richardson  

Solar Physics
February 2018
The physical parameters of the solar wind observed in-situ near 1 AU have been studied for several decades, and relationships between them, such as the positive correlation between the solar wind plasma temperature,   TT , and velocity,   VV , and the negative correlation between density,   NN , and velocity,   VV , are well known. However, the magnetic field intensity,   BB , does not appear to be well correlated with any individual plasma parameter. In this article, we discuss previously under-reported correlations between   BB  and the combined plasma parameters   NV2−−−−√NV2  as well as between   BB  and   NT−−−√NT . These two correlations are strong during periods of corotating interaction regions and high-speed streams, and moderate during intervals of slow solar wind. The results indicate that the magnetic pressure in the solar wind is well correlated both with the plasma dynamic pressure and the thermal pressure.
Solar wind Correlation Magnetic fields CIR