Year: 2020
Type: article
Abstract: The physical mechanisms that produce the slow solar wind are still highly debated. Parker Solar Probe’s (PSP’s) second solar encounter provided a new opportunity to relate in situ measurements of the nascent slow solar wind with white-light images of streamer flows. We exploit data taken by the Solar and Heliospheric Observatory, the Solar TErrestrial RElations Observatory (STEREO), and the Wide Imager on Solar Probe to reveal for the first time a close link between imaged streamer flows and the high-density plasma measured by the Solar Wind Electrons Alphas and Protons (SWEAP) experiment. We identify different types of slow winds measured by PSP that we relate to the spacecraft’s magnetic connectivity (or not) to streamer flows. SWEAP measured high-density and highly variable plasma when PSP was well connected to streamers but more tenuous wind with much weaker density variations when it exited streamer flows. STEREO imaging of the release and propagation of small transients from the Sun to PSP reveals that the spacecraft was continually impacted by the southern edge of streamer transients. The impact of specific density structures is marked by a higher occurrence of magnetic field reversals measured by the FIELDS magnetometers. Magnetic reversals are associated with much stronger density variations inside than outside streamer flows. We tentatively interpret these findings in terms of magnetic reconnection between open magnetic fields and coronal loops with different properties, providing support for the formation of a subset of the slow wind by magnetic reconnection.
Authors: Alexis P. Rouillard, Athanasios Kouloumvakos, Angelos Vourlidas, Justin Kasper, Stuart Bale, Nour-Edine Raouafi, Benoit Lavraud, Russell A. Howard, Guillermo Stenborg, Michael Stevens, Nicolas Poirier, Jackie A. Davies, Phillip Hess, Aleida K. Higginson, Michael Lavarra, Nicholeen M. Viall, Kelly Korreck, Rui F. Pinto, Léa Griton, Victor Réville, Philippe Louarn, Yihong Wu, Kévin Dalmasse, Vincent Génot, Anthony W. Case, Phyllis Whittlesey, Davin Larson, Jasper S. Halekas, Roberto Livi, Keith Goetz, Peter R. Harvey, Robert J. MacDowall, D. Malaspina, M. Pulupa, J. Bonnell, T. Dudok de Witt, Emmanuel Penou
Institutions: Centre National de la Recherche Scientifique, Université Toulouse III - Paul Sabatier, Institut de Recherche en Astrophysique et Planétologie, Johns Hopkins University, Johns Hopkins University Applied Physics Laboratory, Smithsonian Astrophysical Observatory, University of Michigan, Queen Mary University of London, Space Sciences Laboratory, Imperial College London, University of California, Berkeley, United States Naval Research Laboratory, Rutherford Appleton Laboratory, Goddard Space Flight Center, University of Iowa, University of Minnesota, University of Colorado Boulder, Laboratory for Atmospheric and Space Physics, Université d'Orléans, Laboratoire de Physique et Chimie de l’Environnement et de l’Espace
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $1,410
OpenAlex ID: W3000494630