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Abstract Coronal pseudostreamer flux systems have a specific magnetic configuration that influences the morphology and evolution of coronal mass ejections (CMEs) from these regions. Here we continue the analysis of the Wyper et al. magnetohydrodynamic simulation of a CME eruption from an idealized pseudostreamer configuration through the construction of synthetic remote-sensing and in situ observational signatures. We examine the pre-eruption and eruption signatures in extreme ultraviolet and white light from the low corona through the extended solar atmosphere. We calculate synthetic observations corresponding to several Parker Solar Probe–like trajectories at ∼10R⊙to highlight the fine-scale structure of the CME eruption in synthetic WISPR imagery and the differences between the in situ plasma and field signatures of flank and central CME-encounter trajectories. Finally, we conclude with a discussion of several aspects of our simulation results in the context of interpretation and analysis of current and future Parker Solar Probe data.
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Observations of fine coronal structures with high-order solar adaptive optics
Abstract Resolving fine structures in the Sun’s corona may provide key insights into rapid eruptions and the heating of the corona. Adaptive optics systems have been used for over two decades to reach the diffraction limit of large telescopes, thereby compensating for atmospheric image blur. Current systems, however, are still limited to observations of the solar disk and fail with coronal objects, leaving fundamental coronal dynamics hidden in that blur. Here we present observations with coronal adaptive optics reaching the diffraction limit of a 1.6-m telescope to reveal very fine coronal details. Furthermore, we discovered a short-lived, fast-moving, finely twisted feature occurring during the decay phase of a flare that quickly destabilized. Coronal adaptive optics increased the spatial resolution by an order of magnitude at visible wavelengths. We report here a large portion of off-limb coronal rain material with observed scales below 100 km. This new adaptive optics scheme opens opportunities for observational discoveries at small scales beyond the solar limb in the highly dynamic corona by exploiting the diffraction limit of large ground-based telescopes.
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- PAR ID:
- 10593677
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Astronomy
- Volume:
- 9
- Issue:
- 8
- ISSN:
- 2397-3366
- Format(s):
- Medium: X Size: p. 1148-1157
- Size(s):
- p. 1148-1157
- Sponsoring Org:
- National Science Foundation
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