INVESTIGATION OF THE EARTH–DIRECTED HALO CORONAL MASS EJECTIONS (CMEs) DURING SOLAR CYCLES 23 AND 24

This thesis studies on “Investigation of the Earth–directed Halo Coronal Mass Ejections (CMEs) during Solar Cycles 23 and 24”, focusing on their occurrence, characteristics, and impact on Earth's space weather environment. Halo CMEs are crucial because they have the ability to generate geomagnetic storms that impair Earth's technological infrastructure. To identify and analyse Earth-directed halo CMEs, the study uses data from several solar observatories, including the Kodaikanal Solar Observatory, as well as satellite missions such as SOHO and STEREO. Analysing the physical properties of these CMEs, such as speed, angular width, and mass. Assessing the Geo-effectiveness of these CMEs by correlating their properties with geomagnetic storm indices. Identifying the distribution of Earth-directed halo CMEs during Solar Cycles 23 and 24. The results show differences in the frequency and features of Earth-directed halo CMEs across the two solar cycles, shedding light on the changing nature of solar activity and its consequences for space weather prediction. The study also emphasises the importance of continual solar observation and advanced data processing approaches in identifying and managing the threats posed by solar events to current technological infrastructure.