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Title: Identifying the Coronal Source Regions of Solar Wind Streams from Total Solar Eclipse Observations and in situ Measurements Extending over a Solar Cycle
Abstract

This letter capitalizes on a unique set of total solar eclipse observations acquired between 2006 and 2020 in white light, Fexi789.2 nm (Tfexi= 1.2 ± 0.1 MK), and Fexiv530.3 nm (Tfexiv= 1.8 ± 0.1 MK) emission complemented by in situ Fe charge state and proton speed measurements from Advanced Composition Explorer/SWEPAM-SWICS to identify the source regions of different solar wind streams. The eclipse observations reveal the ubiquity of open structures invariably associated with Fexiemission from Fe10+and hence a constant electron temperature,Tc=Tfexi, in the expanding corona. The in situ Fe charge states are found to cluster around Fe10+, independently of the 300–700 km s−1stream speeds, referred to as the continual solar wind. Thus, Fe10+yields the fiducial link between the continual solar wind and itsTfexisources at the Sun. While the spatial distribution of Fexivemission from Fe13+associated with streamers changes throughout the solar cycle, the sporadic appearance of charge states >Fe11+in situ exhibits no cycle dependence regardless of speed. These latter streams are conjectured to be released from hot coronal plasmas at temperatures ≥Tfexivwithin the bulge of streamers and from active regions, driven by the dynamic behavior of prominences magnetically linked to them. The discovery of continual streams of slow, intermediate, and more » fast solar wind characterized by the sameTfexiin the expanding corona places new constraints on the physical processes shaping the solar wind.

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Authors:
; ; ; ; ; ; ; ; ;
Award ID(s):
2028173
Publication Date:
NSF-PAR ID:
10361514
Journal Name:
The Astrophysical Journal Letters
Volume:
911
Issue:
1
Page Range or eLocation-ID:
Article No. L4
ISSN:
2041-8205
Publisher:
DOI PREFIX: 10.3847
Sponsoring Org:
National Science Foundation
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