Likely Common Coronal Source of Solar Wind and 3He-enriched Energetic Particles: Uncoupled Transport from the Low Corona to 0.2 au

D. G. Mitchell; M. E. Hill; D. J. McComas; C. M. S. Cohen; N. A. Schwadron; P. S. Mostafavi; W. H. Matthaeus; N. E. Raouafi; S. T. Al-Nussirat; D. E. Larson; A. Rahmati; J. C. Kasper; P. L. Whittlesey; R. Livi; S. D. Bale; M. Pulupa; J. Giacalone; R. L. McNutt Jr.; E. R. Christian; M. E. Wiedenbeck; T. Sharma

doi:10.3847/1538-4357/ad2467

The Astrophysical Journal (Jan 2024)

Likely Common Coronal Source of Solar Wind and 3He-enriched Energetic Particles: Uncoupled Transport from the Low Corona to 0.2 au

D. G. Mitchell,
M. E. Hill,
D. J. McComas,
C. M. S. Cohen,
N. A. Schwadron,
P. S. Mostafavi,
W. H. Matthaeus,
N. E. Raouafi,
S. T. Al-Nussirat,
D. E. Larson,
A. Rahmati,
J. C. Kasper,
P. L. Whittlesey,
R. Livi,
S. D. Bale,
M. Pulupa,
J. Giacalone,
R. L. McNutt Jr.,
E. R. Christian,
M. E. Wiedenbeck,
T. Sharma

Affiliations

D. G. Mitchell: ORCiD; Johns Hopkins Applied Physics Laboratory , Laurel, MD 20723, USA
M. E. Hill: ORCiD; Johns Hopkins Applied Physics Laboratory , Laurel, MD 20723, USA
D. J. McComas: ORCiD; Department of Astrophysical Sciences, Princeton University , Princeton, NJ 08544, USA
C. M. S. Cohen: ORCiD; California Institute of Technology , Pasadena, CA 91125, USA
N. A. Schwadron: ORCiD; Department of Astrophysical Sciences, Princeton University , Princeton, NJ 08544, USA; Space Science Center, University of New Hampshire , Durham, NH, 03824, USA
P. S. Mostafavi: ORCiD; Johns Hopkins Applied Physics Laboratory , Laurel, MD 20723, USA
W. H. Matthaeus: ORCiD; University of Delaware , Newark, DE 19716, USA
N. E. Raouafi: ORCiD; Johns Hopkins Applied Physics Laboratory , Laurel, MD 20723, USA
S. T. Al-Nussirat: University of California at Berkeley , Berkeley, CA 94720, USA
D. E. Larson: ORCiD; University of California at Berkeley , Berkeley, CA 94720, USA
A. Rahmati: ORCiD; University of California at Berkeley , Berkeley, CA 94720, USA
J. C. Kasper: ORCiD; University of Michigan , Ann Arbor, MI, 48109, USA
P. L. Whittlesey: ORCiD; University of California at Berkeley , Berkeley, CA 94720, USA
R. Livi: ORCiD; University of California at Berkeley , Berkeley, CA 94720, USA
S. D. Bale: ORCiD; University of California at Berkeley , Berkeley, CA 94720, USA
M. Pulupa: ORCiD; University of California at Berkeley , Berkeley, CA 94720, USA
J. Giacalone: ORCiD; Lunar and Planetary Laboratory, University of Arizona , Tucson, AZ 85721, USA
R. L. McNutt Jr.: ORCiD; Johns Hopkins Applied Physics Laboratory , Laurel, MD 20723, USA
E. R. Christian: ORCiD; Goddard Space Flight Center , Greenbelt, MD 20771, USA
M. E. Wiedenbeck: California Institute of Technology , Pasadena, CA 91125, USA
T. Sharma: Department of Astrophysical Sciences, Princeton University , Princeton, NJ 08544, USA

DOI: https://doi.org/10.3847/1538-4357/ad2467
Journal volume & issue: Vol. 965, no. 1
p. 54

Abstract

Read online

Parker Solar Probe (PSP) observations of a small dispersive event on 2022 February 27 and 28 indicate scatter-free propagation as the dominant transport mechanism between the low corona and greater than 35 solar radii. The event occurred during unique orbital conditions that prevailed along specific flux tubes that PSP encountered repeatedly between 25 and 35 R _s during outbound orbit 11. This segment of the PSP orbit exhibits almost stationary angular motion relative to the rotating solar surface, such that in the rotating frame, PSP’s motion is essentially radial. The time dispersion often observed in impulsive solar energetic particle (SEP) events continues in this case down to velocities including the core solar-wind ion velocities. Especially at the onset of this event, the ^3 He content is much larger than the usual SEP abundances seen in the energy range from ∼100 keV to several MeV for helium. Later in the event, iron is enhanced. The compositional signatures suggest this to be an example of an acceleration mechanism for generating the seed energetic particles required by shock (or compression) acceleration models in SEP events to account for the enrichment of various species above solar abundances in such events. A preliminary search of similar orbital conditions over the PSP mission has not revealed additional such events, although favorable conditions (isolated impulsive acceleration and well-ordered magnetic field connection with minimal magnetic field fluctuation) that would be required are infrequently realized, given the small fraction of the PSP trajectory that meets these observation conditions.

Published in The Astrophysical Journal

ISSN: 1538-4357 (Online)
Publisher: IOP Publishing
Country of publisher: United Kingdom
LCC subjects: Science: Astronomy: Astrophysics
Website: https://iopscience.iop.org/journal/0004-637X

About the journal

Abstract

Keywords