Results 1 to 10 of about 355,664 (292)
Flows around Averaged Solar Active Regions. [PDF]
Astrophys J, 2019 Abstract We explore the general properties of near-surface flows around solar active regions. Helioseismic holography is applied to HMI Dopplergrams yielding nearly 5000 flow measurements of 336 unique active regions observed by the Solar Dynamics Observatory between 2010 and 2014.
Braun DC.
europepmc +5 more sources
Information Horizon of Solar Active Regions
The Astrophysical Journal Letters, 2023 Information theory is used to characterize the solar active region periodicities and memories from the Carrington map images 1974–2021. The active regions typically evolve and move from one map to the next.
Jay R. Johnson +3 more
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GLOBAL DYNAMICS OF SUBSURFACE SOLAR ACTIVE REGIONS [PDF]
The Astrophysical Journal, 2012 We present three-dimensional numerical simulations of a magnetic loop evolving in either a convectively stable or unstable rotating shell. The magnetic loop is introduced in the shell in such a way that it is buoyant only in a certain portion in longitude, thus creating an -loop.
Jouve, L., Brun, A.S., Aulanier, G.
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Recurrent solar jets in active regions [PDF]
Astronomy and Astrophysics, 2010 We study the emergence of a toroidal flux tube into the solar atmosphere and its interaction with a pre-existing field of an active region. We investigate the emission of jets as a result of repeated reconnection events between colliding magnetic fields.
Archontis, V. +2 more
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What Are the Causes of Super Activity of Solar Active Regions?
The Astrophysical Journal, 2023 Flare productivity varies among solar active regions (ARs). This study analyzed 20 ARs of contrasting sunspot areas and flare productivities to understand the super flare productivity of certain ARs.
Suman K. Dhakal, Jie Zhang
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The Astrophysical Journal, 2023 The plasma composition of the solar corona is different from that of the solar photosphere. Elements that have a low first ionization potential (FIP) are preferentially transported to the corona and therefore show enhanced abundances in the corona ...
Teodora Mihailescu +8 more
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Deep Learning–based Solar Flare Forecasting Model. III. Extracting Precursors from EUV Images
The Astrophysical Journal Supplement Series, 2023 A solar flare is one of the most intense solar activities, and flare forecasting is necessary to avoid its destructive impact on the near-Earth space environment and technological infrastructure.
Dezhi Sun +3 more
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The Astrophysical Journal, 2023 We begin here a series of papers examining the chromospheric and coronal properties of solar active regions. This first paper describes an extensive data set of images from the Atmospheric Imaging Assembly on the Solar Dynamics Observatory curated for ...
Karin Dissauer +2 more
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The Astrophysical Journal, 2023 The first significant sunquake event of Solar Cycle 25 was observed during the X1.5 flare of 2022 May 10, by the Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamics Observatory.
Alexander G. Kosovichev +2 more
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The Astrophysical Journal, 2023 High-resolution spectral observations of the lower solar atmosphere (chromosphere and transition region) during coronal heating events, in combination with predictions from models of impulsively heated loops, provide powerful diagnostics of the ...
Paola Testa +3 more
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