Results 1 to 10 of about 938 (183)
Differential rotation: the chromosphere to the quiet chromosphere
Monthly Notices of the Royal Astronomical Society, 2023 ABSTRACT Synoptic maps of Ca II K-normalized intensity at ±40° latitude belt from Carrington rotations 827 (1915 August 10) to 1764 (1985 July 7) are utilized to investigate the long-term variation of the quiet chromospheric differential rotation within solar activity cycles through removing some large values of Ca II-normalized ...
, X J Shi, J L Xie
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The mystery of the chromosphere [PDF]
Solar Physics, 1996 We discuss many aspects of the solar chromosphere from an observational point of view, and show that most existing models are in direct contradiction to radio and eclipse measurements. We plead for attention to the actual observed radio temperatures and density gradients, as well as images of the chromosphere.
Zirin Harold, Harold Zirin
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An overall view of temperature oscillations in the solar chromosphere with ALMA [PDF]
Philosophical Transactions Series A, Mathematical, Physical, and Engineering Sciences, 2021 S D T Grant, R J Morton, Bernhard Fleck
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A Comparison Between Cool Chromospheric and Hot Coronal Jets [PDF]
Iranian Journal of Astronomy and Astrophysics, 2023 The similarities between Ca and x-ray jets suggest that their formation mechanism should be the same. Surges are almost cool plasma jets and are usually observed in Hα at ground-based observation, space observations also detect Surges.
Ehsan Tavabi, Azam Mollatayefeh
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Chromospheric Jets and Their Properties [PDF]
Iranian Journal of Astronomy and Astrophysics, 2022 In this study we review solar chromospheric jets and characteristics of them. The chromosphere and transition region are the interface between the solar photosphere and the corona, which plays a key role in the formation and acceleration of the solar ...
Ehsan Tavabi, Sima Zeighami
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Physical Properties of Radio Stars Based on LAMOST Spectral Survey
Universe, 2022 Radio emission has been detected for all types of stars in the Hertzsprung Russell diagram. Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) low and medium-resolution spectroscopic surveys provide a good opportunity to obtain the ...
Liyun Zhang +6 more
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Frontiers in Astronomy and Space Sciences, 2023 The flare activity of the Sun has been studied for decades, using both space- and ground-based telescopes. The former have mainly focused on the corona, while the latter have mostly been used to investigate the conditions in the chromosphere and ...
Alberto Sainz Dalda +4 more
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Dissipation of Magnetohydrodynamic Waves in the Solar Stratified Flux Tubes [PDF]
Iranian Journal of Astronomy and Astrophysics, 2023 Chromosphere is the second layer of the Sun with high variability. The increase of the temperature and the decrease of the density are observed in this layer. This unusual behavior is one of the most important problems in the solar corona.
Zahra Fazel
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A CHROMOSPHERIC CONUNDRUM? [PDF]
The Astrophysical Journal, 2010 We examine spectra of the Ca II H line, obtained under good seeing conditions with the VTT Echelle Spectrograph in June of 2007, and higher resolution data of the Ca II 8542 Angstrom line from Fabry-Perot instruments. The VTT targets were areas near disk center which included quiet Sun and some dispersed plage.
Judge, Philip +3 more
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The quiet sun at mm wavelengths as seen by ALMA
Frontiers in Astronomy and Space Sciences, 2022 Solar observations at sub-mm, mm and cm wavelengths offer a straightforward diagnostic of physical conditions in the solar atmosphere because they yield measurement of brightness temperature which, for optically thick features, equals intrinsic ...
Costas E. Alissandrakis +2 more
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