Results 21 to 30 of about 2,361 (168)
The solar corona above active regions: A comparison of extreme ultraviolet line emission with radio emission [PDF]
Solar Physics, 1967 The observations of extreme ultraviolet (EUV) emission lines of Feix through Fe XVI made by OSO-I have been applied to a study of the solar corona above active regions. Ultraviolet and radio emission are determined for several levels of activity classified according to the type of sunspot group associated with the active region. Both radio emission and
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Synthetic Extreme-ultraviolet Emissions Modulated by Leaky Fast Sausage Modes in Solar Active Region Loops [PDF]
The Astrophysical Journal, 2019 Abstract We study the extreme-ultraviolet (EUV) emissions modulated by leaky fast sausage modes (FSMs) in solar active region (AR) loops and examine their observational signatures via spectrometers like the EUV imaging spectrometer (EIS). After computing fluid variables of leaky FSMs with magnetohydrodynamic (MHD) simulations, we forward-
Mijie Shi +3 more
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The Astrophysical JournalThe extreme-ultraviolet (EUV) late phase (ELP) is the second increase of the irradiance of warm coronal lines during solar flares, and has a crucial impact on the Earth’s ionosphere.
Ya Wang +2 more
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A rotating tomographic imager for solar extreme-ultraviolet/soft X-ray emission
The Astrophysical Journal, 1992 A concept is presented for a high-resolution EUV/soft-X-ray imager that has much in common with the medical imaging procedure of tomography. The resulting instrument is compatible with a simpler, less costly spin-axis-stabilized spacecraft. To demonstrate the fidelity of the reconstruction procedure, the observation and reconstruction is simulated to ...
Joseph M. Davila, W. T. Thompson
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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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Multistage Reconnection Powering a Solar Coronal Jet
The Astrophysical Journal, 2023 Coronal jets are short-lived eruptive features commonly observed in polar coronal holes and are thought to play a key role in the transfer of mass and energy into the solar corona.
David M. Long +7 more
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The Astrophysical Journal Supplement SeriesDespite a wealth of multiwavelength, spatially resolved, time-domain solar activity data, an accurate and complete temporospatial solar flare census is unavailable, which impedes our understanding of the physics of flare production.
Jorge R. Padial Doble +1 more
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Genesis of a Confined X6.4 Flare in a Quadrupolar Magnetic Configuration
The Astrophysical JournalBoth eruptive and confined flares—those having and lacking, respectively, an associated large-scale coronal mass ejection—are frequently observed in solar active regions (ARs).
Chunming Zhu +5 more
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Evidence of Extreme-ultraviolet Resonant Excitation in the Middle Corona during a Solar Flare
The Astrophysical JournalWe present observations of an eruptive solar flare on 2016 January 6 that occurred behind the solar limb from the perspective of the Earth, but was well observed by the Solar-Terrestrial Relations Observatory (or STEREO) and the Solar Extreme Ultraviolet
Daniel B. Seaton +12 more
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The Astrophysical JournalAbstract We present a study of the influence of solar UV anisotropy on the heliospheric backscatter helioglow generated by resonant scattering of solar Lyα photons on interstellar hydrogen atoms around the Sun. Simulations based on the WawHelioGlow model suggest that the response of the helioglow pole-to-ecliptic ratio to the anisotropy
M. Strumik, M. Bzowski, M. A. Kubiak
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