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Title: The Detectability of Coronal Mass Ejections in the Low Corona Using Multislit Extreme-ultraviolet Spectroscopy
Abstract The spectra of coronal mass ejections (CMEs) in the low corona play a crucial role in understanding their origins and physical mechanisms and enhancing space weather forecasting. However, capturing these spectra faces significant challenges. This paper introduces a scheme of a multislit spectrometer design with five slits, acquiring the global spectra of the solar corona simultaneously with a focus on the spectra of CMEs in the low corona. The chosen wavelength range of the spectrometer (170–180 Å) includes four extreme ultraviolet emission lines (Fex174.53 Å, Feix171.07 Å, Fex175.26 Å, Fex177.24 Å), which provides information on the plasma velocity, density, and temperature. Utilizing a numerical simulation of the global corona for both the on-disk and the off-limb scenarios, we focus on resolving the ambiguity associated with various Doppler velocity components of CMEs, particularly for a fast CME in the low corona. A new application of our decomposition technique is adopted, enabling the successful identification of multiple discrete CME velocity components. Our findings demonstrate a strong correlation between the synthetic model spectra and the inverted results, indicating the robustness of our decomposition method and its significant potential for global monitoring of the solar corona, including CMEs.  more » « less
Award ID(s):
1854790
PAR ID:
10620834
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
The Astrophysical Journal
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
984
Issue:
2
ISSN:
0004-637X
Page Range / eLocation ID:
141
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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