Fine Structure of Metric Type-IV Radio Bursts Observed with the ARTEMIS-IV Radio Spectrograph: Association with Flares and Coronal Mass Ejections

摘要

Fine structures embedded in type-IV burst continua may be used as diagnosticsof the magnetic field restructuring and the corresponding energy releaseassociated with the low corona development of flare/CME events. A catalog of 36type-IV bursts observed with the SAO receiver of the ARTEMIS-IV solarradio-spectrograph in the 450--270 MHz range at high cadence (0.01 sec) wascompiled; the fine structures were classified into five basic classes with twoor more sub-classes each. The time of fine structure emission was compared withthe injection of energetic electrons as evidenced by HXR and microwaveemission, the SXR light-curves and the CME onset time. Our results indicate avery good temporal association between energy release episodes and pulsations,spikes, narrow-band bursts of the type-III family and zebra bursts. Of theremaining categories, the featureless broadband continuum starts near the timeof the first energy release, between the CME onset and the SXR peak, butextends for several tens of minutes after that, covering almost the full extentof the flare--CME event. The intermediate drift bursts, fibers in theirmajority, mostly follow the first energy release but have a wider distribution,compared to other fine structures.