| 其他摘要 | Solar jets are ubiquitous, transient plasma ejecting phenomena in the solar atmosphere, including spicules, macrospicules, coronal jets, and so on. These unique and fascinating solar activities occur over a broad spatial range, whose length/width may vary from 6.5/0.3 Mm to 400/100 Mm. These multi-scale plasma ejections eject mass and energy flux into the upper atmosphere, likely contributing to the coronal heating and the acceleration of solar wind. Despite many observational and theoretical advances over the past few decades, the triggering mechanism, acceleration process, and energy release of solar jets are still not fully understood. Whether solar jets occurring over different spatial scales have a similar origin needs further study. This paper focuses on the above issues. Taking advantage of high spatiotemporal resolution multi-wavelength data from the space and ground observation instruments, we have investigated the coronal jet associated energy release phenomenon and the origin of small-scale jet activity (macrospicules) and also explored the self-similarity of multi-scale jet events in their physical nature. This paper mainly includes the following aspects:(1) Using imaging and radio multi-wavelength observations, we studied a coronal jet associated energy release in a coupled magnetic system. The jet occurred under a small-scale fan-spine configuration that was inseted within a large-scale pseudostreamer. This unique magnetic system provided clues to the interpretation of the various physical phenomena we observed. This research work reveals that the type III radio burst and the on-disk fast-moving radio source are homogenous electrons accelerated by the same physical process (i.e., the null-point reconnection) but propagated along different field system. Additionally, we also discuss the generation mechanism of the QFP wave associated with the jet. Our study has important implications for understanding the energy release and particle acceleration mechanisms of the solar coronal jets. (2) With high-resolution observations from the New Vacuum Solar Telescope and Solar Dynamics Observatory, we have investigated the origin of five groups of recurrent active-region macrospicules. Before the launch of each macrospicule, we detect a compact bright patch (BP) at its base, where a newly emerging dipole contacts and cancels with the preexisting ambient field. The spectral diagnosis from the Interface Region Imaging Spectrograph at one of BPs reveals signatures of reconnection at the lower atmosphere. We suggest that these macrospicules and related BPs form in a common reconnection process, in which the increasing reconnection height between the emerging dipole and the ambient field results in the observed variations from BPs to macrospicules. Interestingly, most macrospicules show similar characteristics to larger-scale coronal jets and/or smaller-scale spicules, i.e., the rotating motions, the presence of mini-filaments and BPs before the eruptions, and magnetic flux emergence and cancellation. We studied the detailed evolution process of the base of the macrospicules, providing evidence that the macrospicules are associated with emergence-cancellation-driven reconnection. Our study provides important new clues to understanding the driving mechanism of spicules and has important significance for the self-similarity between the formation mechanisms of multi-scale solar jet activity.(3) Study on twin-structure coronal mass ejections can help us understand the cause of coronal mass ejections (CMEs) formation. Using SDO/AIA and STEREO/EUVI, we conducted a small sample statistical study of seven jet-twin structure CMEs ((referred to as twin CMEs)) and nine jet-narrow CMEs. Among them, we analyze in detail four examples of twin CMEs, all of which consist of both jet-like compnent and bubble-like component. We find that both twin CMEs and narrow CMEs involve interchange reconnection of open and closed fields during their formation. The jet formed by the filaments are destroyed extends to the high corona to form a narrow CME or a jet-like component of the twin CME. But during this reconnection interchange process, the large magnetic loops driving outward expansion by the formation of the jet by the filaments leads to the creation of the bubble-like component in the twin CME. This is different from the previous explanation of the cause of twin CME formation. Our study is revealing for the understanding of bubble (or loop shape) CMEs without core magnetic field structure, providing further observational constraints for the self-similarity theory of solar eruptive activity phenomena. |
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