Tadpoles in Wavelet Spectra of a Solar Decimetric Radio Burst

In the solar decimetric type IV radio event observed on 2001 June 13, we have found wavelet tadpole patterns for the first time. They were detected simultaneously at all radio frequencies in the 1.1-4.5 GHz frequency range. The characteristic period of the wavelet tadpole patterns was found to be 70.9 s. The parameters of the tadpoles on different frequencies are very similar and the correlations between individual radio fluxes are high. These tadpoles are interpreted as a signature of the magnetoacoustic wave train moving along the flare loop through the radio source and modulating its gyrosynchrotron emission.