Results 1 to 10 of about 10,085,228 (216)
MHD Simulation of a Solar Eruption from Active Region 11429 Driven by a Photospheric Velocity Field
The Astrophysical Journal Letters, 2023 Abstract Data-driven simulation is becoming an important approach for realistically characterizing the configuration and evolution of solar active regions, revealing the onset mechanism of solar eruption events, and hopefully achieving the goal of accurate space weather forecasting, which is beyond the scope of any existing theoretical ...
Xinyi Wang, Chaowei Jiang, Xueshang Feng
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Magnetic and Velocity Field Topology in Active Regions of Descending Phase of Solar Cycle 23 [PDF]
Solar Physics, 2020 23 pages, 11 figures, Accepted for publication in Solar ...
R. A. Maurya, A. Ambastha
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Large Photospheric Doppler Shift in Solar Active Region 12673. I. Field-aligned Flows
The Astrophysical Journal, 2023 Delta ( δ ) sunspots sometimes host fast photospheric flows along the central magnetic polarity inversion line (PIL). Here we study the strong Doppler shift signature in the central penumbral light bridge of solar active region NOAA 12673.
Jiayi Liu +5 more
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Video Magnetic Field and Velocity Fields of Solar Flares and Relative Active Region [PDF]
International Astronomical Union Colloquium, 1989 By means of Solar Magnetic Field Telescope, the fine structure of video magnetic fields (5324A) and sight-of-line velocity fields (4861A) of flare active region on July 23 (E53, S19) and Aug. 8(W25, S28) in 1987 has been obtained. The main characters are following:1.
Ai Guoxiang, Li Jing
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Expulsion of Counter Evershed Flows from Sunspot Penumbrae
The Astrophysical Journal, 2023 In addition to the Evershed flow directed from the umbra toward the outer boundary of a sunspot, under special circumstances a counter Evershed flow (CEF) in the opposite direction also occurs.
J. S. Castellanos Durán +2 more
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Proceedings of the International Astronomical Union, 2023 AbstractIn this article, the physical processes occurring in the convective layer and the photosphere of the Sun and their connection to the formation of active regions (ARs) and the development of the corresponding magnetic field are explored. Specifically, we test the magnetic flux emergence hypothesis and based on the line-of-sight magnetic field ...
A. M. Sadykov, S. A. Krasotkin
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The Astrophysical Journal, 2023 The distribution and evolution of photospheric magnetic fields in sunspots, plages, and network, and variations in their relative flux content, play key roles in radial velocity (RV) fluctuations observed in Sun-as-a-star spectra.
Anisha Sen, S. P. Rajaguru
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The Astrophysical Journal, 2023 Using time–distance local helioseismology flow maps within 1 Mm of the solar photosphere, we detect inflows toward activity belts that contribute to solar-cycle scale variations in the near-surface meridional flow. These inflows stretch out as far as 30°
Sushant S. Mahajan +2 more
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Flows and Nonthermal Velocities in Solar Active Regions Observed with the EUV Imaging Spectrometer onHinode: A Tracer of Active Region Sources of Heliospheric Magnetic Fields? [PDF]
The Astrophysical Journal, 2008 From Doppler velocity maps of active regions constructed from spectra obtained by the Extreme-ultraviolet Imaging Spectrometer (EIS) on the Hinode spacecraft we observe large areas of outflow (20-50 km/s) that can persist for at least a day. These outflows occur in areas of active regions that are faint in coronal spectral lines formed at typical quiet
Doschek, G. A. +6 more
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Novel Approach to Forecasting Photospheric Emergence of Active Regions
The Astrophysical Journal Letters, 2023 One key aspect of understanding the solar dynamo mechanism and the evolution of solar magnetism is to properly describe the emergence of solar active regions.
S. S. A. Silva +11 more
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