Results 11 to 20 of about 14,596 (161)
Numerical Simulation of Coronal Waves Interacting with Coronal Holes. II. Dependence on Alfvén Speed Inside the Coronal Hole [PDF]
The Astrophysical Journal, 2018 Abstract We used our newly developed magnetohydrodynamic (MHD) code to perform 2.5D simulations of a fast-mode MHD wave interacting with coronal holes (CHs) of varying Alfvén speed that result from assuming different CH densities. We find that this interaction leads to effects like reflection, transmission, stationary fronts at the CH ...
Isabell Piantschitsch +6 more
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Variations in Daily Maximum Areas and Longitudinal Widths of Solar Coronal Holes in 2017–2020
Universe, 2022 We considered coronal holes as a manifestation of the large-scale magnetic field of the Sun. The main goal of this work was to study the variations in the largest areas and longitudinal widths of solar coronal holes observed daily in the polar and mid ...
Alexandr Riehokainen +6 more
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The Astrophysical Journal, 2023 This paper is dedicated to the new implicit unstructured coronal code COCONUT, which aims at providing fast and accurate inputs for space-weather forecasting as an alternative to empirical models.
Barbara Perri +7 more
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The Astrophysical Journal Letters, 2023 The omnipresence of transient fluctuations in the solar wind, such as switchbacks (SBs) and small-scale magnetic flux ropes (SMFRs), have been well observed by the in situ observation of Parker Solar Probe (PSP), yet their sources are not clear. Possible
Nengyi Huang +2 more
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Journal of Space Weather and Space Climate, 2021 We discuss the significant implications of three eye-witness drawings of the total solar eclipse on 1706 May 12 in comparison with two on 1715 May 3, for our understanding of space climate change.
Hayakawa Hisashi +5 more
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The Astrophysical Journal, 2009 Here, we explore the nature of small-scale jet-like structures and their possible relation to explosive events and other known transient features, like spicules and macrospicules, using high-resolution spectroscopy obtained with the Solar and Heliospheric Observatory/Solar Ultraviolet Measurements of Emitted Radiation instrument.
Scullion, E. +4 more
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The Fine-scale Structure of Polar Coronal Holes
The Astrophysical Journal, 2023 Coronal holes are thought to be composed of relatively broad columnar structures known as plumes. Here, we demonstrate that the plumes (and interplumes) in polar coronal holes are composed of fine-scale filamentary structure, with average scales of 2″–10″
R. J. Morton, R. Cunningham
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Velocity Structure of Jets in a Coronal Hole [PDF]
Publications of the Astronomical Society of Japan, 2007 Abstract The velocity structures of jets in a coronal hole have been derived for the first time. Hinode observations revealed the existence of many bright points in coronal holes. They are loop-shaped and sometimes associated with coronal jets. Spectra obtained with the Extreme-ultraviolet Imaging Spectrometer aboard Hinode were analyzed
Kamio, Suguru +6 more
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DIPOLAR EVOLUTION IN A CORONAL HOLE REGION [PDF]
The Astrophysical Journal, 2009 Using observations from the SOHO, STEREO and Hinode, we investigate magnetic field evolution in an equatorial coronal hole region. Two dipoles emerge one by one. The negative element of the first dipole disappears due to the interaction with the positive element of the second dipole. During this process, a jet and a plasma eruption are observed.
Yang, S., Zhang, J., Borrero, J.
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Coronal holes and solar-terrestrial relationships
Geofísica Internacional, 1991 En este trabajo se discute el papel que juegan los hoyos coronales del Sol en las perturbaciones del viento solar y en las alteraciones del ambiente terrestre.
S. Bravo
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