Detection of “Diffuse” Coronal He I 1083 During the April 8, 2024 Solar Eclipse: Evidence for Terrestrial Atmospheric Scattering Contribution

IF 2.4 3区物理与天体物理 Q2 ASTRONOMY & ASTROPHYSICS

Solar Physics Pub Date : 2025-06-27 DOI:10.1007/s11207-025-02500-5

Momchil E. Molnar, Roberto Casini, Paul Bryans, Ben Berkey, Kalista Tyson

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引用次数: 0

Abstract

Strong He i 1083 nm atomic line signals have previously been measured during total solar eclipses at coronal heights above the lunar limb. These rather unexpected measurements have kindled a discussion about the suggested presence of significant amounts of neutral helium at coronal conditions. We performed spectroscopic observations of the He i 1083 nm wavelength region during the April 8th, 2024 total solar eclipse, using an instrument specifically designed to test the presence of He i 1083 in the solar corona. We were able to detect the He i 1083 line, the forbidden coronal line of Fe xiii at 1074.7 nm, as well as the chromospheric H i 1093.8 nm (Paschen-\(\gamma \)) line in our data. The chromospheric He i 1083 nm and H i 1093.8 nm lines were detected in both the corona and on the lunar disc. We hypothesize that our observations support a terrestrial atmospheric scattering of the solar flash spectrum as the origin of the He i 1083 signal during the April 8th, 2024 eclipse. Our findings challenge the notion of abundant neutral helium in the solar corona suggested by previous eclipse observations.

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2024年4月8日日食期间“漫射”日冕He I 1083的探测：陆地大气散射贡献的证据

强He i 1083 nm原子线信号已经在日全食期间在月缘以上日冕高度被测量到。这些出乎意料的测量结果引发了一场关于日冕条件下存在大量中性氦的讨论。在2024年4月8日日全食期间，我们使用专门设计的仪器对He i 1083波长区域进行了光谱观测，以测试He i 1083在日冕中的存在。我们能够在我们的数据中检测到He i 1083线，Fe xiii在1074.7 nm的禁止日冕线，以及色球H i 1093.8 nm （Paschen- \(\gamma \)）线。在日冕和月盘上均检测到He 1083 nm和He 1093.8 nm的色球谱线。我们假设，在2024年4月8日日食期间，我们的观测结果支持地球大气对太阳闪光光谱的散射，这是He i 1083信号的来源。我们的发现挑战了以前日食观测中提出的日冕中存在大量中性氦的观点。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Solar Physics 地学天文-天文与天体物理

CiteScore

5.10

自引率

17.90%

发文量

146

审稿时长

1 months

期刊介绍： Solar Physics was founded in 1967 and is the principal journal for the publication of the results of fundamental research on the Sun. The journal treats all aspects of solar physics, ranging from the internal structure of the Sun and its evolution to the outer corona and solar wind in interplanetary space. Papers on solar-terrestrial physics and on stellar research are also published when their results have a direct bearing on our understanding of the Sun.