| 其他摘要 | In the past several decades, various solar eruptive activities have been observed anywhere at anytime in the solar atmosphere. For example, solar flares, filament eruptions, jets, coronal mass ejections, wave phenomena, etc. Previous observations have indicated that solar magnetic field plays a dominant role in the evolution processes of all types of solar activities. Since many large scale solar eruptive activities can cause significant effect on the space environment of the Earth as well as the modern life of human, studying and forecasting the solar activities is an urgent task. In addition, the Sun is the nearest star from us, people can directly observe and study it in great details. Hence, studying the Sun should contribute significant value for studying other stars in the universe. This thesis mainly focuses on the multi-wavelength, high-temporal and high-spatial resolution observations of three types of solar activities: the filament eruptions, the coronal jets and the coronal waves. By analyzing various observations taken by ground-based and space-borne instruments, I try to understand and figure out the inherent physical mechanisms and construct models to interpret these solar eruptive activities. For the filament eruptions, I study the triggering mechanism and the impact factors of one failed filament eruption in Chapter 3. I find that the amount of energy release of the flare is a key impact factor for the fate of a filament eruption. In Chapter 4, I report two sympathetic events, including one partial and one full filament eruptions, in a quadrupolar magnetic source region. Our analysis results indicate that the magnetic implosion could be used to link the two filament eruptions, and the structural properties of coronal fields are important for producing sympathetic eruptions. For coronal jets, I study an unwinding polar coronal jet in Chapter 5 and a coronal blowout jet in Chapter 6, respectively. For the unwinding polar coronal jet, it exhibited obvious transverse expansion during its ejection period, which underwent three distinct phases: the slow expansion phase, the fast expansion phase and the steady phase. I find that the non-potential magnetic field in the jet can supply the energy for the coronal jet. For the coronal blowout jet, I first report that a coronal blowout jet can be associated with a simultaneous bubble-like and a jet-like coronal mass ejection in one solar event. Based on our analysis results, I propose a physical model to interpret the observed coronal blowout jet. I also study three coronal wave events in this thesis. In Chapter 7, a wave event that exhibits quasi-periodic fast propagating (QFP) magnetosonic waves is studied, as well as the associated pulsation flare. I find that almost all the frequencies of the flare are consistent with that of the QFP waves, which is revealed by the k-omega diagram of the QFP waves. In the meantime, a few low frequencies revealed by the $k$--$\omega$ diagram of the QFP waves could not be found from the flare light curves. I propose that both the periodicity of the flare and the QFP waves are excited by a common physical origin, while the low frequencies of the QFP waves result from the leakage of the pressure-driven p-mode oscillations from the photosphere. The origin and the basic physical nature of large scale coronal waves still remain mysterious. In Chapter 8, I report a coronal wave that can be observed simultaneously in the solar photosphere, chromosphere, transition region and low corona. Our analysis results indicate that this wave should be a coronal shock wave driven by the expanding flanks of the associated coronal mass ejection. The wave signatures observed in the lower solar atmosphere are caused by the sweeping of the shock wave traveling in the corona. The physical nature of this wave is a fast mode of magnetosonic wave. Another coronal wave is presented in Chapter 9. By studying the interaction of the wave with some magnetic structures along its propagation path, I find that the wave manifests a lot of wave effects such as reflection and refraction. I propose that this coronal wave is a nonlinear fast magnetosonic wave driven by the expanding flanks of the associated coronal mass ejection. Along with the fast development of many new ground-based and space-borne solar telescopes, high quality observation will certainly help us to reveal the true physics behind various solar eruptive activities. |
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