Prospective Implications of Extreme-ultraviolet Coronal Plumes for Magnetic-network Genesis of Coronal Heating, Coronal-hole Solar Wind, and Solar-wind Magnetic Field Switchbacks

Abstract

We propose that coronal heating in EUV coronal plumes is weaker, not stronger, than in adjacent nonplume coronal magnetic funnels. This expectation stems from (i) the observation that an EUV plume is born as the magnetic flux at the foot of the plume’s magnetic funnel becomes tightly packed, and (ii) the observation that coronal heating in quiet regions increases in proportion to the coastline length of the underlying magnetic network. We do not rule out the possibility that coronal heating in EUV plumes might be stronger, not weaker, but we point out how the opposite is plausible. We reason that increasing coronal heating during plume birth would cause co-temporal increasing net upward mass flux in the plume, whereas decreasing coronal heating during plume birth would cause co-temporal net downward mass flux in quiet-region plumes and co-temporal decrease in net upward mass flux or even net downward mass flux in coronal-hole plumes. We further reason that conclusive evidence of weaker coronal heating in EUV plumes would strengthen the possibility that magnetic-twist waves from fine-scale magnetic explosions at the edges of the magnetic network (1) power much of the coronal heating in quiet regions, and (2) power most of the coronal heating and solar-wind acceleration in coronal holes, with many twist waves surviving to become magnetic field switchbacks in the solar wind from coronal holes.

Keywords

• Solar coronal plumes
• Solar coronal heating
• Solar wind
• Solar extreme ultraviolet emission
• Solar coronal holes