Observational And Theoretical Research On The Fiber Fine Structure Of Solar Radio Bursts

Solar activity, especially, Coronal Mass Ejection (CME) during a large solar activity affected the space environment of human being and could be one of main reasons of the space disaster. Theoretical researches on solar activity, solar flare and CME were involved in many fields of foundational physics such as plasma astrophysics, magnetohydrodynamics (MHD) and so on. The forecast of solar activity, a main branch of Space Weather, was becoming more and more significant for preventing space disaster and for many aspects of space science. Furthermore the 'microflare theory' tried to discuss and find the elementary flares in small space and time scale which might form and trigger the whole solar flare. The detection of radio fine structures showed many observational evidences of 'microflare'. The observations and theoretical researches on radio fine structure have been developed fast recently and played an important role in solar radio astrophysics.The Bastille-Day flare of 14 July 2000, a great solar flare with X-ray/Ha importance of X5.7/B3, was observed around 10:24 UT in the NOAA 9077 AR at position N22W07. In this flare, very rich interesting radio bursts and fine radio spectral structures were detected, not only in metric wave band, but also in decimetric and microwave band (1.0-7.6 GHz by National Astronomical Observatories of Chinese Academy of Sciences - NAOC). The event gave us a good opportunity to discuss the processes of magnetic change, energy release and particle acceleration in the corona during the preflare, especially using decimetric and microwave fine structure data.In this thesis, we report the solar type IV bursts and its associated fiber fine structures recorded on 14 July 2000. A theoretical interpretation for the fibers is based upon the model of a magnetic-mirror loop configuration in the solar corona. In this model, the source of the fiber emission is considered as the ducting of whistler solitons within the magnetic-mirror loop. Using this model, we estimate the magnetic field strength and the relevant space scale of the emission source area.In Chap.1 of this dissertation, we introduce the background of solar activity, solar radio research and radio emission theory. In Chap.2, the observational characteristics of the radio burst of the Bastille event were discussed in detail. In Chap.3, we described the associated foundational theories with the model of a magnetic-mirror loop, consisting of the flux duct, the magnetic reconnection, the plasma wave, the wave-wave interaction and so on. Then in Chap.4, using the model of magnetic-mirror loop to estimate quantitatively, we obtain the magnetic field strength, the number of solitons in a single fiber source, the volume of the source and the ducting parameters. Finally we give out some conclusions and discussions.