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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.
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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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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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Solar Activity and Regional Climate [PDF]
Radiocarbon, 2001 We performed a statistical analysis of the data on summer temperature anomalies in northern Fennoscandia (8–1995 AD) and found that a 70–130-yr cycle is present in this series during most of the time period. A comparison of the reconstructed northern Fennoscandia temperature with different indicators of solar activity (Wolf numbers, the length of solar
M G Ogurtsov +4 more
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The Astrophysical Journal Supplement Series, 2023 It is well accepted that the physical properties obtained from the solar magnetic field observations of active regions (ARs) are related to solar eruptions.
Jingjing Wang +3 more
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