The Spiral Interplanetary Magnetic Field: A Polarity Sense and Solar Plasma Indices during Three Solar Cycles (22-24) using the Wavelet Transforms

Abstract

Abstract In this study, we analyzed the monthly average of "toward" and "away" groups of solar plasma parameters: plasma density (N), plasma temperature (T), plasma flow pressure (P), and solar wind speed (V), during the interval 9/1986-12/2019, covering three solar activity cycles 22-24, based on the polarity of the interplanetary magnetic field (IMF). We investigated the symmetry and asymmetry of these plasma properties by applying the wavelet transform methods; continuous wavelet, cross-wavelet, and wavelet coherence to the monthly averages determined by the IMF's daily polarity. The continuous wavelet transform revealed the periodic features of each plasma parameter for both polarity groups. To explore synchronization and interconnections between these parameters, we employed cross-wavelet and wavelet coherence transforms, illustrating the phase relationships between the "toward" and "away" groups for each plasma parameter. The results of continuous wavelet transform indicated that, unlike in solar cycles 22 and 24, the solar cycle 23 exhibited symmetry and correlation between the "toward" and "away" groups concerning solar wind speed. Throughout solar cycles 22-24, solar plasma characteristics displayed dynamic interactions and varying periodicities, with a noticeable shift from asymmetry to greater symmetry between the two polarity groups. In solar cycle 24, both plasma temperature and pressure in the "toward" and "away" groups exhibited more frequent periodicities. The results of cross-wavelet and wavelet coherence transforms confirmed the continuous wavelet transform findings by identifying phase relationships between the two polarity groups during common periods. Notably, in solar cycle 24, prominent quasi-periodicities of 1.7, 4.5, and 5.4 years were observed.