Observational properties and theoretical aspects of type IV solar radio bursts are much less studied than those of the type III bursts; the observational properties of fine structures in type IV bursts are even less known around 3.0 GHz than around 300 MHz. Since Oct. 1996, a spectrometer with high time and frequency resolution at the Beijing Astronomical Observatory (BAO) has been recording solar bursts in the frequency range 2.60-3.80 GHz. The first event with complicated fine structures was recorded on Apr. 15 1998.
We will emphasise three special fine structures of a kind that we had never recorded before in such a high frequency range (around 3.60 GHz). We will discuss these features in relation to previously identified structures at lower frequencies (around 300 MHz), such as the "zebra patterns" and the "evolving emission line" (EEL) reported by Chernov et al. in 1998.
In Sect. 2, we will describe the instrument and the main features of the event. In Sect. 3, we will analyse and properties of three fine strutures. In Sect. 4, we will discuss what they might be. We will conclude in Sect. 5.
© European Southern Observatory (ESO) 2000
Online publication: January 29, 2001