Blowout Expansion of Overlying Coronal Loops and Subsequent Filament Eruption: AIA and RHESSI Observations

Abstract We present a comprehensive multiwavelength analysis of a coronal mass ejection (CME) on 2014 January 8 from the active region (AR) NOAA 11947 by analyzing the data from Atmospheric Imaging Assembly (AIA) on board Solar Dynamics Observatory, RHESSI, and Hiraiso Radio Spectrograph. The CME is associated with an M3.6 flare and filament eruption. Observations from the AIA 171 Å images reveal the origin of pre-CME arcade ≈1 hr prior to the eruptive event. Before the onset of event, the hot AIA 131 and 94 Å images exhibit an existence of a hot flux rope, which on eruption results in the activation and eruptive expansion of the pre-CME coronal arcade. The eruptive process of pre-CME arcade consists of a slow rise evolution with a speed ≈3 km s −1 , “arcade-to-bubble” transformation, and blowout expansion of the CME-bubble with a fast speed of ≈400 km s −1 . A differential emission measure analysis suggests the presence of multithermal plasma in the bubble-structure and strong plasma heating at the core of the AR. A blowout expansion of CME is accompanied with multiple type III and a split-band type II radio bursts in association with X-ray emission up to 50 keV energies from its source region. Our observations reveal that the formation and expansion of the CME-bubble serve as the earliest signatures of the CME, capturing its development in the low corona. Concurrent X-ray and radio emissions further highlight the critical role of large-scale magnetic reconnection in powering both the flare emissions and the early evolution and dynamics of the CME.