Multi-point study of the energy release and impulsive CME dynamics in an eruptive C7 flare

Abstract

We combine observations from different vantage points to perform a detailed study of a long duration eruptive C7 class flare that occurred on 17 April 2021 and was partially occulted from Earth view. The dynamics and thermal properties of the flare-related plasma flows, the flaring arcade, and the energy releases and particle acceleration are studied together with the kinematic evolution of the associated CME in order to place this long duration event in context of previous eruptive flare studies. The flare showed hard X-ray (HXR) bursts over the duration of an hour in two phases lasting from 16:04 UT to 17:05 UT. During the first phase, a strong increase in emission from hot plasma and impulsive acceleration of the CME was observed. The CME acceleration profile shows a three-part evolution of slow rise, acceleration, and propagation in line with the first STIX HXR burst phase, which is triggered by a rising hot (14 MK) plasmoid. During the CME acceleration phase, we find signatures of ongoing magnetic reconnection behind the erupting structure, in agreement with the standard eruptive flare scenario. The subsequent HXR bursts that occur about 30 minutes after the primary CME acceleration show a spectral hardening (from $\delta \approx$ 7 to $\delta \approx$ 4) but do not correspond to further CME acceleration and chromospheric evaporation. Therefore, the CME-flare feedback relationship may only be of significance within the first 25 minutes of the event under study, as thereafter the flare and the CME eruption evolve independently of each other.

References in corpus (18)

• The Solar Orbiter mission -- Science overview
• An Observational Overview of Solar Flares
• Differential Emission Measures from the Regularized Inversion of Hinode and SDO data
• Implications of X-ray Observations for Electron Acceleration and Propagation in Solar Flares
• The origin, early evolution and predictability of solar eruptions
• Different Power-law Indices in the Frequency Distributions of Flares with and without Coronal Mass Ejections
• Microwave and Hard X-Ray Observations of the 2017 September 10 Solar Limb Flare
• Combined STEREO/RHESSI study of CME acceleration and particle acceleration in solar flares
• From coronal observations to MHD simulations, the building blocks for 3D models of solar flares
• Genesis and impulsive evolution of the 2017 September 10 coronal mass ejection
• Global Energetics of Solar Flares: II. Thermal Energies
• The Origin of Underdense Plasma Downflows Associated with Magnetic Reconnection in Solar Flares
• Statistics of coronal dimmings associated with coronal mass ejections. II. Relationship between coronal dimmings and their associated CMEs
• MEM_GE: a new maximum entropy method for image reconstruction from solar X-ray visibilities
• How Does Magnetic Reconnection Drive the Early Stage Evolution of Coronal Mass Ejections?
• Solar Flare-CME Coupling Throughout Two Acceleration Phases of a Fast CME
• Sunspot number second differences as a precursor of the following 11-year sunspot cycle
• Multi-instrument STIX microflare study

Cited by in corpus (2)

• On the three-dimensional relation between the coronal dimming, erupting filament and CME. Case study of the 28 October 2021 X1.0 event
• Three-part structure of solar coronal mass ejection observed in low coronal signatures of Solar Orbiter