The Dynamic Formation of Pseudostreamers

Abstract Streamers and pseudostreamers structure the corona at largest scales, as seen in both eclipse coronagraph white-light images. Their inverted-goblet appearance encloses broad coronal loops Sun tapers to a narrow radial stalk away from star. The streamer associated with global solar dipole magnetic field is long-lived, predominantly contains single arcade of nested within it, separates opposite-polarity interplanetary fields heliospheric current sheet (HCS) anchored its apex. Pseudostreamers, on other hand, are transient, enclose double arcades loops, separate like-polarity dense plasma sheet. We use numerical magnetohydrodynamic simulations calculate, for first time, formation response photospheric magnetic-field evolution. Convective transport minority-polarity flux concentration, initially positioned under one side streamer, through boundary into adjacent preexisting hole forms pseudostreamer. Interchange reconnection overlying null point(s) governs development pseudostreamer above—and new satellite behind—the moving minority polarity. dynamics liberate coronal-loop that can escape heliosphere along so-called separatrix-web (“S-Web”) arcs, which reach far HCS equatorial plane, explain origin high-latitude slow wind. describe implications our results situ remote-sensing observations obtained, most recently, by Parker Solar Probe Orbiter.