The Study Of Solar Surges, Jets And Their Associated Phenomena

In this thesis,some observational and theoretical progresses in the study of solar surges,jets and other related dynamical phenomena are reviewed,and my works about the spatial and temporal relationships between surges and jets and their physical origin are introduced during the period of my specializing in PHD. The thesis consists of three parts.The first chapter is review,the second to the fourth ones are my works and the last chapter is the problems and prospects. Our main contributions are as follows:1.Studying seven successive Hαsurge events,we found that:at their base region,the opposite photospheric longitudinal fluxes emerged,converged and were canceled by each other.Correspondingly,a small satellite spot emerged, decayed and disappeared during a period of about 2 hours in the white-light observations. The dynamic properties of the surges,such as the transverse velocity, projected maximum length and lifetime,varied in wide ranges.They are 30-200 km s^-1,38 000-220 000 km and from several to tens of minutes,respectively. Correspondingly,the intensities of their correlated microflares were different too. Prior to these surge events,a small Hαarch filament connecting the opposite flux elements was found at the base region.Instead of erupting completely,it gradually disappeared during the surges.Its role in the surge activities is very like a bipolar flux,which contained the cool plasma and reconnected with the ambient magnetic fields.In 1600(?),three surge events exhibited the composite structures of bright jets and nearby small flaring loops,which provides direct evidence of magnetic reconnection origin of the surges.A careful comparison revealed that the ends of the arch filament,the UV jets and the small flaring loops just corresponded to the interacting longitudinal fluxes in the photosphere. These observational results support the magnetic reconnection model of surges and jets.2.we present a detailed study of an EUV jet and the associated Hαfilament eruption in a major flare in the active region NOAA 10044 on 2002 July 29.In the data of Hαline wings,a small filament was found to erupt out from the magnetic neutral line of the active region during the flare.Two bright EUV loops were observed rising and expanding with the filament eruption,and both hot and cool EUV plasma ejections were observed to form the EUV jet.The two thermal components spatially separated from each other and lasted for about 25 minutes.In the white-light corona data,a narrow coronal mass ejection(CME) was found to well respond to this EUV jet.We cannot found obvious emerging flux on the photosphere accounting for the filament eruption and the EUV jet. On the contrary,significant sunspot decaying and magnetic flux cancellation due to collision of opposite flux before the events were noticed.Based on the hard X-ray data by RHESSI,which showed the evidence of magnetic reconnection along the main magnetic neutral line,we think that all the observed dynamical phenomena,including the EUV jet,filament eruption,flare and CME,should have a close relation to the flux cancellation in the low atmosphere.3.We analyzed multi-wavelength observations of three surges with a recurrent period of about 70 min in Hα,EUV,and soft X-ray,which occurred in the quiet-sun region on 2000 November 3.These homologous surges were associated with small flares at the same base,but their exact footpoints were spatially separated from the flare.Each surge consisted of a cool Hαcomponent and a hot, EUV or soft X-ray component,which showed different evolutions not only in space but also in time.The EUV jets had slightly converging shapes,underwent more complicate development,showed clearly twisting structures,and appeared to open to space.The Hαsurges,however,were smaller and only traced the edges of the jets.They always occurred later than the jets but had dark EUV counterparts appearing in the bright jets.These surge activities were closely associated with two emerging bipoles and their driven flux cancellations at the base region,and were consistent with the magnetic reconnection surge model.