Near-Sun Switchback Boundaries: Dissipation with Solar Distance
نویسندگان
چکیده
The most surprising result from the first solar encounters by Parker Solar Probe (PSP) is large amount of brief magnetic field reversals often referred to as switchbacks. Switchbacks have previously been observed further downstream in wind spacecraft such Helios 2 at 62 Rs Sun. However, these observations lack a distinct proton temperature increase detected inside switchbacks PSP, implying that they are evolving over time eventually reach pressure balance switchback boundaries. We look evolution boundaries function radial distance Sun, closest approach 35.7 during PSP's two beyond 80 Rs. Using and data FIELDS SWEAP instruments, we perform day-by-day superposed epoch analysis 25 with sharpest step-like During both found spikes gradually decline before vanishing completely around 55 Magnetic velocity also steadily drop magnitude, but flatten out instead disappearing. Most interestingly, change ΔTp across × 105 magnitude below 40 outbound trajectory, an order less on inbound suggesting possible common characteristics near encounters.
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2021
ISSN: ['2041-8213', '2041-8205']
DOI: https://doi.org/10.3847/1538-4357/ac079f