Eruption and Interplanetary Evolution of a Stealthy Streamer-Blowout CME Observed by PSP at ${\sim}$0.5~AU

TL;DR

This study analyzes a stealthy streamer-blowout CME observed by PSP at 0.5 AU, revealing its initiation, magnetic erosion, and interaction with heliospheric structures, enhancing understanding of such CMEs during solar minimum.

Contribution

It provides new insights into the initiation and magnetic erosion of SBO-CMEs, highlighting their interaction with heliospheric magnetic fields using PSP observations.

Findings

18% magnetic flux erosion due to reconnection

CME initiation linked to multi-stage sympathetic breakout

Interaction with heliospheric magnetic structures observed

Abstract

Streamer-blowout coronal mass ejections (SBO-CMEs) are the dominant CME population during solar minimum. Although they are typically slow and lack clear low-coronal signatures, they can cause geomagnetic storms. With the aid of extrapolated coronal fields and remote observations of the off-limb low corona, we study the initiation of an SBO-CME preceded by consecutive CME eruptions consistent with a multi-stage sympathetic breakout scenario. From inner-heliospheric Parker Solar Probe (PSP) observations, it is evident that the SBO-CME is interacting with the heliospheric magnetic field and plasma sheet structures draped about the CME flux rope. We estimate that $18 \, \pm \, 11\%$ of the CME's azimuthal magnetic flux has been eroded through magnetic reconnection and that this erosion began after a heliospheric distance of ${\sim}0.35$ AU from the Sun was reached. This observational study has important implications for understanding the initiation of SBO-CMEs and their interaction with the heliospheric surroundings.