The Heliospheric Current Sheet and Plasma Sheet during Parker Solar Probe’s First Orbit
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Author
Lavraud, B.Fargette, N.
Réville, V.
Szabo, A.
Huang, J.
Rouillard, A. P.
Viall, N.
Phan, T. D.
Kasper, J. C.
Bale, S. D.

Berthomier, M.
Bonnell, J. W.
Case, A. W.
Dudok de Wit, T.
Eastwood, J. P.
Génot, V.
Goetz, K.
Griton, L. S.
Halekas, J. S
Harvey, P.
Kieokaew, R.
Klein, K. G.
Korreck, K. E.
Kouloumvakos, A.
Larson, D. E.
Lavarra, M.
Livi, R.
Louarn, P.
MacDowall, R. J.
Maksimovic, M.
Malaspina, D.
Nieves-Chinchilla, T.
Pinto, R. F.
Poirier, N.
Pulupa, M.
Raouafi, N. E.
Stevens, M. L.
Toledo-Redondo, S.
Whittlesey, P. L.
Affiliation
Univ Arizona, Lunar & Planetary LabIssue Date
2020-05-08Keywords
Slow solar windSolar coronal streamers
Solar coronal transients
Heliosphere
Solar magnetic reconnection
Space plasmas
Plasma jets
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IOP PUBLISHING LTDCitation
Lavraud, B., Fargette, N., Réville, V., Szabo, A., Huang, J., Rouillard, A. P., ... & Whittlesey, P. L. (2020). The Heliospheric Current Sheet and Plasma Sheet during Parker Solar Probe’s First Orbit. The Astrophysical Journal Letters, 894(2), L19.Journal
ASTROPHYSICAL JOURNAL LETTERSRights
© 2020. The American Astronomical Society. All rights reserved.Collection Information
This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.Abstract
We present heliospheric current sheet (HCS) and plasma sheet (HPS) observations during Parker Solar Probe's (PSP) first orbit around the Sun. We focus on the eight intervals that display a true sector boundary (TSB; based on suprathermal electron pitch angle distributions) with one or several associated current sheets. The analysis shows that (1) the main density enhancements in the vicinity of the TSB and HCS are typically associated with electron strahl dropouts, implying magnetic disconnection from the Sun, (2) the density enhancements are just about twice that in the surrounding regions, suggesting mixing of plasmas from each side of the HCS, (3) the velocity changes at the main boundaries are either correlated or anticorrelated with magnetic field changes, consistent with magnetic reconnection, (4) there often exists a layer of disconnected magnetic field just outside the high-density regions, in agreement with a reconnected topology, (5) while a few cases consist of short-lived density and velocity changes, compatible with short-duration reconnection exhausts, most events are much longer and show the presence of flux ropes interleaved with higher-beta regions. These findings are consistent with the transient release of density blobs and flux ropes through sequential magnetic reconnection at the tip of the helmet streamer. The data also demonstrate that, at least during PSP's first orbit, the only structure that may be defined as the HPS is the density structure that results from magnetic reconnection, and its byproducts, likely released near the tip of the helmet streamer.ISSN
2041-8205EISSN
2041-8213Version
Final published versionae974a485f413a2113503eed53cd6c53
10.3847/2041-8213/ab8d2d
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