We introduced the decimetric and metric solar radio spectrometers of Yunnan Astronomical Observatories (YNAO) working in the frequency range of 625– 1500 MHz and 70–700 MHz, respectively. Many solar radio bursts have been observed. In these events, various types of decimetric and metric fine structures with fairly meticulous spectral features were recognized. In addition, we investigate the spectral fine structure of a solar radio burst observed by the Solar Broadband Radio Spectrometer (SBRS) at the Huairou Solar Observing Station (HSOS) in a CME/flare event on December 1, 2004. The data during the impulsive phase of the event display two phases of a zebralike emission patterns, including positively and negatively drifting as well as non-drifting stripes.In addition to the radio data, we also studied the associated data in white-light, EUV, soft and hard X-rays. By comparing with the observational consequences of the standard model of two-ribbon flares, we put forward a possible explanation for these zebra-like patterns, which have even been observed in similar events before, such that they display various patterns of plasma motions. These are sunward motions of plasmoids in the CME/flare reconnecting current sheet and possibly also the termination shock on the loop top and the growth of the flare loop system. We investigated a peculiar metric type II solar radio burst with a broken lane structure, which was observed on November 13, 2012. In addition to the radio data, we also studied the data in the other wavelengths. The events took place from the active region AR 11613 that produced two flares ,the associated CMEs and type II busrts. A long current sheet was developed by the first CME, and the second CME collided with the current sheet first and then merged with the first one. Combing information revealed by the multi-wavelength data indicated that a coronal shock accounting for the type II radio burst, and that the collision of this shock with the current sheet resulted in the broken lane of the type II radio burst. The type II burst lane resumed after the shock passed through the current sheet. We further estimated the thickness of the current sheet according to the gap on the lane of the type II burst, and magnetic field in the two sources region.
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