Investigating the Behavior and Correlation Between Apparent, Total Corrected Sunspot Areas Parameters and the Total Sunspot Brightness Index
Aqeel Z. Azeez & Khalid A. Hadi

Department of Astronomy and Space, College of Science, University of Baghdad, Baghdad, Iraq

Abstract

Sunspot characteristics (Total Apparent Sunspot Area (TASA), Total Corrected Sunspot Area (TCSA), and Total Sunspot Brightness (TSB)) are important indicators of solar activity. In this work, an analytical investigation was conducted of the TASA, TCSA, and TSB datasets observed using the solar science observatory above the Mitaka campus for the years of solar cycle 24 and the ascending phase of solar cycle 25. The study findings showed that the TCSA parameter values were more accurate compared to the TASA parameter data for all months of the years 2009-2024. It also showed that the behavior of the TCSA and TSB parameters exhibited significant fluctuations during the peak of solar cycles 24 and 25 and less variation during the minimum years (2009, 2019). The mathematical correlation tests between the TSB and TCSA parameters, performed for all days/months of the adopted solar cycle years, showed that the exponential regression method yielded better correlation results than other methods. The predicted TCSA parameter results, calculated using the proposed mathematical equation, showed values closer to the observed values obtained from the white light telescope of the solar science observatory. Statistical calculation results of the standard error showed high accuracy in predicting TCSA values during the minimum years and a slight increase (variation) during the maximum years of the studied solar cycles. The statistical calculations of SSreg, SSres, and SSTotal, also showed a clear convergence between the observed and predicted values of the TCSA parameter, while the results of MSreg, MSres, MSTotal, and F-statistics, indicated the reliability of predicting the values of the TCSA parameter compared with the observed data for all the studied years.

Keywords: Sunspots, Corrected Sunspot Area, Sunspot Brightness, Apparent Sunspot Area.

Topic: Earth Physics and Space Science