Abstract Understanding the location and evolution of the cool dense prominence in relation to the large-scale structure of coronal mass ejections (CMEs) is critical to distinguish between different CME initiation mechanisms and to further deepen our understanding of CME evolution through the heliosphere. Combining remote observations of extreme-ultraviolet images and white-light coronagraphs and heliospheric imagers (HIs) obtained from the Solar Dynamics Observatory, Solar and Heliospheric Observatory, STEREO-A, and Solar Orbiter, we present an analysis of the continuous tracking from the corona to interplanetary space of the substructures of a CME associated with a prominence that erupted on 2022 September 23. The prominence is found to remain bright and compact during the CME propagation for more than three days. We investigate the kinematic evolution of the CME substructures as the CME propagated to around 0.5 au. We find that for the first 0.28 au, both the CME front and prominence propagated coherently, indicating that the prominence was tied to the CME magnetic structure. Beyond 0.28 au, the CME bright front was seen to be distorted. However, the prominence continued to propagate at a nearly constant velocity up to at least 0.5 au. STEREO-A/HI images further show a dark ridge-like feature trailing the CME that passed over the prominence, and the prominence appeared tilted. We deduce that the prominence propagated independently of the CME at larger distances from the Sun. Overall, this study shows that both previously proposed hypotheses—namely, that the prominence is tied to or propagates independently of the CME—are valid but within different distance ranges.
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Cospatial Multiwavelength Observations of an Eruptive Prominence as the Bright Core of a Coronal Mass Ejection
Abstract Coronal mass ejections (CMEs), as seen in white-light (WL) coronagraphs, often exhibit a classic three-part structure consisting of a bright front, a dark cavity, and a bright core. With the launch of Solar Orbiter, cospatial imaging of solar eruptions in multiwavelengths of extreme-ultraviolet (EUV) and WL has become available. We present a CME that erupted on 2022 September 23, observed under a uniquely favorable viewing geometry. The CME bright core and its eruptive prominence can be cospatially observed up to a coronal height of 3.5R⊙in the middle corona, in WL using COR1 on board STEREO-A and in EUV using the Full Sun Imager on board Solar Orbiter. Cospatial, multiwavelength observations indicate that the CME bright core observed in WL was almost entirely composed of the prominence material, which was heated during the CME eruption. EUV emissions in 174 and 304 Å of the prominence were largely cospatial when the CME propagated to the middle corona, though subtle differences remained. We further discuss the potential temperature in the bright core region and find that the core was heated as it rose, likely reaching temperatures of about 0.1–0.8 MK.
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- Award ID(s):
- 2301382
- PAR ID:
- 10667775
- Publisher / Repository:
- IOPScience
- Date Published:
- Journal Name:
- The Astrophysical Journal Letters
- Volume:
- 995
- Issue:
- 2
- ISSN:
- 2041-8205
- Page Range / eLocation ID:
- L42
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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