Results 41 to 50 of about 155,544 (195)
Hydrostatic Modeling of the Integrated Soft X-Ray and Extreme Ultraviolet Emission in Solar Active Regions [PDF]
, 2006 Many studies of the solar corona have shown that the observed X-ray luminosity is well correlated with the total unsigned magnetic flux. In this paper we present results from the extensive numerical modeling of active regions observed with the Solar and ...
H. Warren, A. Winebarger
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ALMA Observations of Solar Spicules in a Polar Coronal Hole
The Astrophysical JournalWe report observations of solar spicules at millimeter wavelengths (mm- λ ) using the Atacama Large Millimeter/submillimeter Array (ALMA). These are supplemented by observations in optical, ultraviolet (UV), and extreme ultraviolet (EUV) wavelengths. The
T. S. Bastian +4 more
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Modeling solar extreme ultraviolet irradiance variability using emission measure distributions
Geophysical Research Letters, 1996 We introduce a new model of solar irradiance variability at extreme ultraviolet (EUV) wavelengths. The model combines a spectral emission line database, solar emission measure distributions, and estimates from ground‐based solar images of the fraction of the Sun covered by the various types of activity to synthesize the irradiance.
H. P. Warren +4 more
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Characterizing Chromospheric Condensation with High-cadence Si iv Observations from IRIS
The Astrophysical JournalChromospheric flare ribbons are believed to result from coronal magnetic energy released by reconnection and propagating down to the cooler, lower atmosphere.
Chunming Zhu +3 more
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The Astrophysical Journal, 2022 Abstract The hydrogen Lyα (H i Lyα) emission during solar flares has rarely been studied in spatially resolved images, and its physical origin has not been fully understood. In this paper, we present novel Lyα images for a C1.4 solar flare (SOL2021-08-20T22:00) from the Extreme Ultraviolet Imager aboard Solar Orbiter, together with multi-
Y. Li +9 more
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The solar chromosphere at millimetre and ultraviolet wavelengths [PDF]
Astronomy & Astrophysics, 2019 Solar observations with the Atacama Large Millimeter/submillimeter Array (ALMA) provide us with direct measurements of the brightness temperature in the solar chromosphere.
S. Jafarzadeh +5 more
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Quasi-periodic Pulsation Detected in Lyα Emission During Solar Flares [PDF]
Astrophysical Journal, 2020 We investigated the quasi-periodic pulsation (QPP) in Lyα, X-ray, and extreme-ultraviolet (EUV) emissions during two solar flares, i.e., an X-class (SOL2012-01-27T) and a C-class (SOL2016-02-08T).
Dong Li +5 more
semanticscholar +1 more source
Ultraviolet Variability in Solar-type Members of the M67 Open Cluster
The Astrophysical JournalSolar-type members of the rich, nearly solar-age and solar-metallicity M67 open cluster are systematically investigated for ultraviolet variability. We utilize archival Galaxy Evolution Explorer (GALEX) data, which feature several imaging observation ...
Carl Melis, Ekamjot Kaire
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Observational Signatures of Electron-driven Chromospheric Evaporation in a White-light Flare
The Astrophysical Journal, 2023 We investigate observational signatures of explosive chromospheric evaporation during a white-light flare (WLF) that occurred on 2022 August 27. Using the moment analysis, bisector techniques, and the Gaussian fitting method, redshifted velocities of ...
Dong Li +9 more
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Evolution of the Ratio of Mg ii Intensities during Solar Flares
The Astrophysical JournalThe Mg ii k and h line intensity ratios can be used to probe the characteristics of the plasma in the solar atmosphere. In this study, using the observations recorded by the Interface Region Imaging Spectrometer, we study the variation of the Mg ii k and
Soumya Roy, Durgesh Tripathi
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