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Solar Coronal Lines in the Visible and Infrared: A Rough Guide [PDF]
Astrophysical Journal, 2018 Abstract We review the coronal visible and infrared lines, collecting previous observations and comparing, whenever available, observed radiances to those predicted by various models: the quiet Sun (QS), a moderately active Sun, and an active region as observed near the limb, around 1.1 R ⊙.
Edward Deluca, Giulio Del Zanna
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On the solar coronal lines 1175-1965 A
Astrophysical Journal, 1979 Sixteen new coronal lines are observed in ATM UV spectra. Identifications, wavelengths, and intensities are presented. Two additional lines observed previously are proposed as transitions within the 3p(3)3d configuration of Fe XI.
R Tousey
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Research progress in coronal magnetic field measurements
地球与行星物理论评, 2022 Different solar atmospheric layers are connected by the magnetic field of the Sun, which is the primary source for various types of solar activity. The magnetic activity of the Sun has a significant impact on the solar-terrestrial environment and human ...
Zihao Yang +6 more
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Estimating Ion Temperatures at the Polar Coronal Hole Boundary
The Astrophysical Journal, 2023 The temperatures of the heavy ions ( T _i ) in the solar corona provide critical information about the heating mechanism of the million-degree corona.
Yingjie Zhu, Judit Szente, Enrico Landi
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Identification of Solar Coronal Emission Lines [PDF]
Nature, 1964 THE coronal emission lines are produced by highly ionized atoms undergoing forbidden transitions from metastable levels1. In an attempt to identify further lines we have examined the level separation 3P2—3P1 in the excited four-electron configuration 1s2 2s 2p. Fig. 1 shows the level structure near the ground-state.
P. D. B. COLLINS, M. H. L. PRYCE
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First Infrared Coronal Spectra from DKIST/Cryo-NIRSP: Comparisons with Global MHD Models
The Astrophysical Journal, 2023 The Cryogenic Near-Infrared Spectropolarimeter (Cryo-NIRSP) is now conducting science operations at the National Science Foundation’s Daniel K. Inouye Solar Telescope (DKIST).
Thomas A. Schad +6 more
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ON THE NATURE OF THE SPECTRAL LINE BROADENING IN SOLAR CORONAL DIMMINGS [PDF]
The Astrophysical Journal, 2011 We analyze the profiles of iron emission lines observed in solar coronal dimmings associated with coronal mass ejections, using the EUV Imaging Spectrometer on board Hinode. We quantify line profile distortions with empirical coefficients (asymmetry and peakedness) that compare the fitted Gaussian to the data. We find that the apparent line broadenings
Dolla, Laurent R., Zhukov, Andrei N.
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Are Nonthermal Velocities in Active Region Coronal Loops Anisotropic?
The Astrophysical Journal, 2023 We have measured line widths in active region coronal loops in order to determine whether the nonthermal broadening is anisotropic with respect to the magnetic field direction. These nonthermal velocities are caused by unresolved fluid motions.
Michael Hahn +2 more
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Coronal spectral diagnostics: The coronal solar magnetism observatory (COSMO)
Frontiers in Astronomy and Space Sciences, 2022 The Need: Understanding and predicting the major phenomena taking place in the solar corona, such as flares and Coronal Mass Ejections (CMEs), the heating and evolution of the solar atmosphere, and the acceleration of the solar wind, are fundamental ...
Enrico Landi +9 more
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CAII lines in a quiet region on the Sun I. Dynamic processes in the solar atmosphere
Solar-Terrestrial Physics, 2023 We have studied oscillation processes in the quiet Sun outside a coronal hole at different levels of the solar chromosphere. The study was based on spectroscopic observations of ionized calcium lines (K, H, and 849.8 nm) obtained by the Sayan Solar ...
Turova I. P. +2 more
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