| 其他摘要 | The Sun is the nearest star from the Earth and very ordinary among all stars in the universe. However, the relationship between the sun and human is the closest. The sun's light and heat give birth to all lives on Earth, and maintain human activities, which is necessary for people's living environment. Activities and cycle variations of the sun have a direct impact on the living environment of mankind. Sometimes this influence is beneficial, but sometimes it is destructive. Coronal mass ejections (CMEs) are the most impressive large-scale phenomena occurring on the Sun, which carried about 100,000,000,000 to 10,000,000,000,000 kg magnetized plasma expelled from the sun into interplanetary space in a short period of time. When the ejection is earth-directed, it may lead to a significant disturbance of the earth's magnetic field. Sometimes it could result in the interruption of radio communication, disruption of power grid, the failure of the spacecraft, crew safety as well as harm the development of aerospace. CMEs have been with us ever since the existence of the solar system, yet only in the past century and a half, do they make themselves known to us in that way. The early understanding of the CMEs just limited to the moment when solar eclipses occurred. They became a continuously observable phenomenon only since the Skylab and SOHO era. At present, our understanding of CMEs is not enough. Therefore, understanding CMEs is thus important in protecting ourselves from the CME's potentially devastating effects. Based on a massive document survey and study, we summarized the previous research results on CMEs in chapter one and chapter two. Chapter one includes the observational and statistical properties of CMEs and the main theoretical models of it. Chapter two includes the associated activities and the accompanying phenomena on the solar surface. In chapter three, we studied a eruptive event that involved in a filament eruption, the expansion and eruption of the overlying coronal loops and the formation of a coronal dimming region close to the preexisting eruptive filament. It showed that the CME had a close spatial and temporal relationship with these surface activities, and possibly suggested that the CME was directly originated from the filament and loop's eruption, and the dimming region may supplied mass to it. The chapter four is a summary of this thesis, the open problems of CMEs and the prospects of our future work. |
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