Study of the development of geomagnetic storms in the magnetosphere using solar wind data of three different time resolutions

We study the development of strong geomagnetic storms due to coronal mass ejections in near-Earth space. We compare the time evolution of geomagnetic disturbances with the time variation of solar wind plasma and field parameters with special attention to the development of the main-phase of the geomagnetic storms. We use geomagnetic indices and solar wind parameters of three different time resolutions (1 hour, 5-minutes, and 1-minute) for the analysis, and determine the time-lag between them during the development of the geomagnetic storms. The time-lag has been determined for the 10 selected geomagnetic storms of different strength (weakest geomagnetic storm with Dst=−88\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$= -88$\end{document} nT and strongest geomagnetic storm with Dst=−422\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$= -422$\end{document} nT) and different main-phase durations (shortest main-phase duration ≈ 4 hours, and longest main-phase ≈ 21 hours). These results will lead us towards better understanding of onset and the development of geomagnetic storms and ultimately the solar wind-magnetosphere coupling.