Mapping solar variability of equatorial sunspots and plasma flows

Authors

DOI:

https://doi.org/10.14295/bjs.v3i9.638

Keywords:

sunspot numbers, solar magnetic field, plasma flows, solar differential rotation, meridional circulation, magnetic induction equation

Abstract

This study investigated the variability of equatorial sunspots and plasma flows, focusing on the detailed dynamics of solar activity revealed by sunspot data analysis and magnetic field evolution. The goals were to investigate the relationship between sunspot numbers with differential rotation, meridional circulation, and magnetic induction using observational data and theoretical models. The methods included studying historical sunspot data from 1700 to the present and using time series decomposition to find trends, seasonality, and residuals. The evolution of the solar magnetic field was predicted using the magnetic induction equation, which considers plasma flow and magnetic diffusion effects. The real sunspot data were combined with the simulated magnetic field data to investigate their relationship over time. Contour maps were created to illustrate the spatiotemporal evolution of the magnetic field, and correlation studies were used to quantify the correlations between sunspot numbers and key solar dynamics characteristics. Key studies show that the Sun rotates differentially, with latitudinal zones rotating at differing angular velocities, influencing sunspot generation. A strong connection (0.8192) between the sunspot numbers and meridional velocity demonstrates the influence of large-scale plasma flows on sunspot activity. Despite this, the monthly averaged magnetic field strength and sunspot numbers exhibited a minor correlation (0.004507), showing that solar activity is affected by independent underlying processes or phases. Magnetic field evolution contour maps show differences from 1x1013 to 2x1013 Gauss at different spatial (40 km to 80 km) and temporal scales (from start to the present in months). This evolution is governed by the magnetic induction equation, which includes the effects of plasma flow and magnetic diffusion. The paper also emphasizes the alpha effect's significance in producing poloidal magnetic fields from toroidal fields via turbulent convection, which is essential to the solar dynamo mechanism. In conclusion, this study provides a comprehensive analysis of equatorial sunspots and plasma flows, offering insights into the solar cycle and laying the groundwork for future research in solar and space weather prediction.

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Published

2024-07-20

How to Cite

Goshu, B. S. (2024). Mapping solar variability of equatorial sunspots and plasma flows. Brazilian Journal of Science, 3(9), 49–64. https://doi.org/10.14295/bjs.v3i9.638

Issue

Vol. 3 No. 9 (2024): Brazilian Journal of Science

Section

Exact Sciences

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Copyright (c) 2024 Belay Sitotaw Goshu

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