SH049-0006
Small-scale Magnetic Flux Ropes in the First Two Parker Solar Probe Encounters

Wednesday, 16 December 2020
Poster
Yu Chen1, Qiang Hu1,2, Lingling Zhao2, Justin Christophe Kasper3, Stuart D Bale4, Kelly E Korreck5, Anthony W Case5, Michael Louis Stevens5, John W Bonnell4, Keith Goetz6, Peter Harvey4, Kristopher G. Klein7, Davin Larson4, Roberto Livi4, Robert J MacDowall8, David Malaspina9, Marc Pulupa4 and Phyllis L Whittlesey4, (1)University of Alabama in Huntsville, Department of Space Science, Huntsville, AL, United States, (2)Center for Space Plasma and Aeronomic Research, Huntsville, AL, United States, (3)University of Michigan, Climate and Space Sciences and Engineering, Ann Arbor, MI, United States, (4)Space Sciences Laboratory, University of California Berkeley, Berkeley, CA, United States, (5)Smithsonian Astrophysical Observatory, Cambridge, MA, United States, (6)University of Minnesota, School of Physics and Astronomy, Minneapolis, MN, United States, (7)University of Arizona, Lunar and Planetary Laboratory, Tucson, AZ, United States, (8)NASA/Goddard Space Flight Center, Greenbelt, United States, (9)University of Colorado, Astrophysical and Planetary Sciences Department, Boulder, CO, United States
Abstract:
Small-scale magnetic flux ropes (SFRs) are a type of structures in the solar wind that possess helical magnetic field lines. In a recent report (Chen and Hu 2020), we presented the radial variations of the properties of SFR from 0.29 to 8 au using in situ measurements from the Helios, ACE/Wind, Ulysses, and Voyager spacecraft. With the launch of the Parker Solar Probe (PSP), we extend our previous investigation further into the inner heliosphere. We apply a Grad-Shafranov-based algorithm to identify SFRs during the first two PSP encounters. We find that the number of SFRs detected near the Sun is much less than that at larger radial distances, where magnetohydrodynamic (MHD) turbulence may act as the local source to produce these structures. The prevalence of Alfvenic structures significantly suppresses the detection of SFRs at closer distances. We compare the SFR event list with other event identification methods, yielding a dozen well-matched events. The cross-section maps of two selected events confirm the cylindrical magnetic flux rope configuration. The power-law relation between the SFR magnetic field and heliocentric distances seems to hold down to 0.16 au.
<< Previous Abstract | Next Abstract >>