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arXiv · 2001.08716

Morphological Reconstruction of a Small Transient Observed by Parker Solar Probe on 2018 November 5

Brian E. Wood·Phillip Hess·Russell A. Howard·Guillermo Stenborg·Yi-Ming Wang
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Abstract

On 2018 November 5, about 24 hours before the first close perihelion passage of Parker Solar Probe (PSP), a coronal mass ejection (CME) entered the field of view of the inner detector of the Wide-field Imager for Solar PRobe (WISPR) instrument onboard PSP, with the northward component of its trajectory carrying the leading edge of the CME off the top edge of the detector about four hours after its first appearance. We connect this event to a very small jet-like transient observed from 1 au by coronagraphs on both the SOlar and Heliospheric Observatory (SOHO) and the A component of the Solar TErrestrial RElations Observatory mission (STEREO-A). This allows us to make the first three-dimensional reconstruction of a CME structure considering both observations made very close to the Sun and images from two observatories at 1 au. The CME may be small and jet-like as viewed from 1 au, but the close-in vantage point of PSP/WISPR demonstrates that it is not intrinsically jet-like, but instead has a structure consistent with a flux rope morphology. Based on its appearance in the SOHO and STEREO-A images, the event belongs in the "streamer blob" class of transients, but its kinematic behavior is very unusual, with a more impulsive acceleration than previously studied blobs.

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Brian E. Wood, Phillip Hess, Russell A. Howard, Guillermo Stenborg, Yi-Ming Wang. 2020-01-23. Morphological Reconstruction of a Small Transient Observed by Parker Solar Probe on 2018 November 5. https://doi.org/10.3847/1538-4365/ab5219

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