Simulations of structured upflows from plumes and their connection to the solar wind

TL;DR

This study uses advanced 3D simulations to explore how structured plasma outflows from coronal hole plumes, driven by magnetic topologies like QSLs, contribute to the solar wind without relying on interchange reconnection.

Contribution

It introduces a novel simulation approach revealing that plasma outflows along QSLs can sustain the solar wind independently of interchange reconnection.

Findings

Outflows transition from cool downflows to hot upflows at plume interfaces.

Mass fluxes significantly exceed observed solar wind loss rates.

Structured outflows are channeled along QSLs at open field boundaries.

Abstract

Small-scale transient jetlet activity and associated upflows from coronal hole plumes are potential sources of the solar wind. To elucidate the magnetic origins and driving mechanisms of such upflows, we perform three-dimensional radiative magnetohydrodynamic simulations using the MURaM code, spanning from the upper convection zone to the low corona. We synthesize Fe\,{\sc x} 174\,{\AA} emission to capture the plume evolution comparable to observations, examining underlying plasma flows, thermal structures, and magnetic topologies. We identify a pronounced transition from cool downflows in the lower atmosphere to hot upflows in the corona at the interface between plume-rooted like-polarity flux concentrations. These upflows are threaded by a complex, filamentary network of Quasi-Separatrix Layers (QSLs) -- a topology distinct from standard interchange reconnection scenarios. The domain-averaged mass flux over a 38-minute interval ranges from $10^{-9}$ to $10^{-8}\,\mathrm{g\,cm^{-2}\,s^{-1}}$, substantially exceeding observed solar-wind loss rates. Our results demonstrate that highly structured plasma outflows are channeled along strong QSLs at open--open field boundaries, providing a pathway to sustain the solar wind from coronal-hole plumes without requiring interchange reconnection triggered by opposite-polarity flux emergence.