Narrowband dm-Spikes in the 2 GHz Frequency Range and MHD Cascading Waves in Reconnection Outflows

Two examples of clouds of narrowband dm-spikes, observed by the Ondřejov radiospectrograph in the 1-2 GHz frequency range, are analyzed. After transformation of the frequency scales to distances in the solar atmosphere, the power spectra analysis of size scales reveals a spectral index of −5/3, resembling that of Kolmogorov spectra of turbulent cascades. The narrowband dm-spikes are interpreted as radio emission from electrons accelerated in MHD cascading waves, probably generated in plasma outflows from magnetic field reconnection.