Sources of the Multi-Lane Type II Solar Radio Burst on 5 November 2014

Abstract

We report the well-observed event of a multi-lane type II solar radio burst with a combined analysis of radio dynamic spectra and radio and extreme-ultraviolet (EUV) imaging data. The burst is associated with an EUV wave driven by a coronal mass ejection (CME) that is accompanied by a GOES X-ray M7.9 flare on 5 November 2014. This type of event is rarely observed with such a complete data set. The type II burst presents three episodes (referred to as A, B, and C), characterized by a sudden change in spectral drift, and contains more than ten branches, including both harmonic-fundamental (H–F) pairs and split bands. The sources of the three episodes present a general outward propagating trend. There exists a significant morphology change from single source (Episode A) to double source (Episode B). Episode C maintains the double-source morphology at 150 MHz (no imaging data are available at a lower frequency). The double-source centroids are separated by $\sim300 ^{\prime\prime}$ to $500^{\prime\prime}$ . The southeastern (SE) source is likely the continuation of the source of Episode A since both are at the same section of the shock (i.e. the EUV wave) and close to each other. The northwestern (NW) source is coincident with (thus, possibly originates from) the interaction of the shock with a nearby mini-streamer-like structure. Comparing the simultaneously observed sources of the F and H branches of Episode A, we find that their centroids are separated by less than $200^{\prime \prime}$ . The centroids of the split bands of Episode B are cospatial within the observational uncertainties. This study shows the source evolution of a multi-lane type II burst and the source locations of different lanes relative to each other and to the EUV wave generated by a CME. The study indicates the intrinsic complexity underlying a type II dynamic spectrum.