Direct observations of a complex coronal web driving highly structured slow solar wind

Abstract

The solar wind consists of continuous streams of charged particles that escape into the heliosphere from the Sun, and is split into fast and slow components, with the fast wind emerging from the interiors of coronal holes. Near the ecliptic plane, the fast wind from low-latitude coronal holes is interspersed with a highly structured slow solar wind, the source regions and drivers of which are poorly understood. Here we report extreme-ultraviolet observations that reveal a spatially complex web of magnetized plasma structures that persistently interact and reconnect in the middle corona. Coronagraphic white-light images show concurrent emergence of slow wind streams over these coronal web structures. With advanced global magnetohydrodynamics coronal models, we demonstrate that the observed coronal web is a direct imprint of the magnetic separatrix web (S-web). By revealing a highly dynamic portion of the S-web, our observations open a window into important middle-coronal processes that appear to play a key role in driving the structured slow solar wind.

Observational Evidence of S-web Source of the Slow Solar Wind

“…Interchange reconnection is also induced in pseudo-streamer configurations at their null points and separators (Aslanyan et al 2021). Recently, Chitta et al (2023) presented extremeultraviolet (EUV) and white-light observations of the highly structured mid-corona that show indications of the interchange reconnection dynamics consistent with the MHD simulations of the S-web.…”

The Solar Minimum Eclipse of 2019 July 2. III. Inferring the Coronal T e with a Radiative Differential Emission Measure Inversion

“…These very different streamer temperatures indicate that there are never truly "quiet-Sun" streamers but rather different levels of activity and dynamics that can create quite unique structures. Chitta et al (2023) recently found similar fine-scale structures, complexity, and diversity of coronal streamers using white-light and EUV observations along with MHD modeling-albeit without any T e measurement.…”

Observations of Mini Coronal Dimmings Caused by Small-scale Eruptions in the Quiet Sun

“…The mass and magnetic free energy can be transferred from the lower corona to the middle or higher corona, which could become a possible source of the solar wind. Chitta et al (2023) gave a direct observational evidence for a coronal separatrix web driving highly structured slow solar wind through complex middle-coronal dynamic processes. Perhaps the minifilament eruption we observed could transport mass and energy to the middle or higher corona, which then becomes the solar wind through the mechanism proposed by their research.…”