Zongjun Ning

We analyse 22 continuous microwave reverse slope (RS) type III and 21 microwave pulsation groups observed by the Purple Mountain Observatory (PMO) spectrometer over the frequency range of 4.5-7.5 GHz from 1999-2003. The RS type III groups have an average of 12 bursts per group, a mean duration of 0.1-2 s around 6 GHz, a mean quasi-period of s and a mean drift rate of 7.0 GHz s-1. The shortest quasi-period is measurable down to 0.05 s thanks to the high time resolution of this instrument. The microwave pulsation groups have an average of 22 events per group, a mean duration of 3-4 s and a mean quasi-period of s. The RS type III bursts have the same quasi-period as the upward type III bursts documented before. We discuss two possible origins of the quasi-periodicity of type III bursts. One is the quasi-periodic process in magnetic reconnection at the same site, and the other is spatially unresolved stochastic processes in solar flares.

We present the observational results of the solar bursts on the band of 1-80 GHz (NORH) associated with both a CME and a flare on Oct. 26 2003. This event shows two parts of radio bursts in the time profile. The first part is associated with an X1.2 flare. However, the following part seams related to both the flare and the CME, as the radio emission is enhanced while the is decreasing. Thus, these two parts of radio bursts may originate from different physical processes, i.e., flare and CME shock. A primary study is performed on the difference between this two parts.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

We present two remarkable “decimetric pulsation” events (DCIM) around the time 1998 0415 0800, detected by spectrometers (1.00–2.00 GHz and 2.60–3.80 GHz) at Beijing Astronomical Observatory (BAO). High-resolution dynamic spectra reveal various fine structures, such as spike groups, pulsations, type-III bursts, patches, and zebra patterns or evolving emission lines on the rising phase of the second DCIM around 3 GHz. It is the first time that such a wealth of fine features have been detected in a same type IV-DCIM event; it is also the first time that blips pairs simultaneously drifting towards the same frequency have been recorded; it is the second time to observe an evolving emission line, and the first above 1 GHz.