Results 91 to 100 of about 860 (219)
The Astrophysical JournalWe present the application of the data-driven branch of the MURaM code to the extensively studied flare-productive Active Region 11158. We refine the hybrid model strategy—which has been described in the earlier papers of this series—to model the ...
Feng Chen
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Solar-terrestrial response to large extension or long-duration solar gamma ray events [PDF]
Geofísica Internacional, 2000 Gamma ray lines (GRL) from the large event of 29 September 1989 were observed from a site about 25 degrees from the flare site. In June 1991, at least three long-duration GRL events were observed by several spacecraft.
A. Méndez Berhondo +3 more
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Chromospheric and coronal activity in solar-like stars
, 2008 The term "stellar activity" summarizes a number of phenomena on the stellar surface and in the stellar atmosphere. The origin of many of these phenomena are changes in the structure of the stellar magnetic field. While it is possible to directly observe different forms of activity on the Sun in great detail, this remains impossible for other stars ...
openaire +2 more sources
What does solar chromospheric activity look like under different inclination angles? [PDF]
Astronomy & AstrophysicsContext. Chromospheric observations in the Ca II lines are essential for studying the magnetic activity of stars. In the case of the Sun, the chromospheric plages, the main contributors to the Ca II K emission, are distributed between midlatitude and the equator and never close to the poles. Therefore, we suspect that the inclination angle of the solar
G. Vanden Broeck +3 more
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The Astrophysical JournalWe performed numerical simulations of magnetic reconnection with different strengths of magnetic fields from the solar photosphere to the upper chromosphere.
Abdullah Zafar +7 more
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Serbian Astronomical Journal, 2017 A study of variations of solar spectral irradiance (SSI) in the wave-length ranges 121.5 nm-300.5 nm for the period 1981-2009 is presented. We used various data for ultraviolet (UV) spectral lines and international sunspot number (ISSN) from interactive data centers such as SME (NSSDC), UARS (GDAAC), SORCE (LISIRD) and SIDC, respectively ...
Goker, U. D. +2 more
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Topological structure of the magnetic solar corona
, 2007 The solar corona is a highly complex and active plasma environment, containing many exotic phenomena such as solar flares, coronal mass ejections, prominences, coronal loops, and bright points.
Maclean, Rhona Claire
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The Astrophysical JournalWe report on a flare-driven coronal rain event observed along postflare loops during the decay phase of an X1.6-class solar flare. Although high-resolution studies of flare-driven coronal rain have been conducted, imaging spectroscopic studies are rare ...
Donguk Song +8 more
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The Astrophysical Journal, 1993 The secular evolution of solar-type chromospheres is studied through a detailed comparison of the present Sun (G2 V) with the very old (≃9.5 Gyr) star β Hyi (G2 IV). In such old stars one might observe the lowest possible levels of stellar activity. Detailed studies of various atmospheric layers in β Hyi have been made, and this Paper II in the series ...
D. Dravins +3 more
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Macrospicules, Jets and the Solar Chromosphere [PDF]
, 2017 Given recent advancements in observational solar physics, both in quality and quan- tity, the time is right to revise the chromospheric feature, macrospicules.
Bennett, Samuel M
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