Speaker
Description
Detailed interferometric radio observations of solar activity allow us to constrain the dynamics of high-energy electron beams accelerated in flares and coronal mass ejections (CME), and thus to better model and study space weather effects. We report here a comparative analysis of two similar solar activity periods observed by LOFAR LBA on September 24 and 28, 2023. Both events exhibited the same radio burst sequence: an episode of strong type III bursts followed several minutes later by a type II burst in metric wavelengths, drifting between 80-20 MHz frequency. To understand these events comprehensively, we combined LOFAR observations with optical and EUV data. We employ a novel approach to processing 1-second time resolution LOFAR solar interferometry, and apply a new method for automated source extraction and measurement. During both eruptive events we observe distinct active emission regions in the solar corona, which correspond to the radio bursts and electron beams detected in situ (for the September 24 events). We investigate the dynamics of the type II solar radio sources from LOFAR interferometry for both September 24 and 28 events to understand the common physical processes underlying this type III – type II burst sequence.
