Group of type III bursts and its associated spikes

National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, PR China

Corresponding author: S. J. Wang, wsj@sun10.bao.ac.cn or wsj888@263.net

Received: 6 March 2001
Accepted: 2 May 2001

Abstract

A group of type III bursts in solar radio bursts, observed with the 2.6-3.8 GHz spectrometer of the Beijing Astronomical Observatory on April 15 1998, is selected and analyzed. The type III bursts are associated with a large number of spikes, which have been recorded by the spectrometer at high temporal resolution (8 ms). We report the observational characteristics of the type III bursts and the corresponding spikes including duration, frequency bandwidth, drift rate and quasi-periodicity. Afterwards we discuss the space scale, the brightness temperature and the magnetic field strength at the emission source region. Finally we investigate the mechanism which would cause the quasi-periodicity of the type III bursts and the short time scale of the spikes theoretically. It is suggested that the type III bursts and the spikes differ clearly between their source regions in the space scale, the brightness temperature, the magnetic field strength and the magnetic structure.