Results 191 to 200 of about 5,382 (223)

Twist of magnetic fields in solar active regions

Astronomy Reports, 2002
We study the twist properties of photospheric magnetic fields in solar active regions using magnetographic data on 422 active regions obtained at the Huairou Solar Observing Station in 1988–1997. We calculate the mean twist (force-free field αf) of the active regions and compare it with the mean current-helicity density of these same active regions, h
Hongqi Zhang, Shudong Bao, Kirill M. Kuzanyan   +2 more
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Solar Flare Acceleration of Solar Wind: Influence of Active Region Magnetic Field

Science, 1981
The direction of the photospheric magnetic field at the site of a solar flare is a good predictor of whether the flare will accelerate solar wind plasma. If the field has a southward component, high-speed solar wind plasma is usually observed near the earth about 4 days later. If the field has a northward component, such high-speed solar wind is almost
H, Lundstedt, J M, Wilcox, P H, Scherrer
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Photographic maps of magnetic fields of solar active regions

Chinese Astronomy, 1979
This paper describes our daily photography of maps of the strong magnetic fields in solar active regions. In one case, the isogauss line at 2000 G in a complex magnetic region is seen to coincide with the optical outline of a sunspot umbra.
null Ding You-ji, null Peng Fang-lin, null Zhong Shu-hua, null Li Bo-shu, null Ye Hui-lian, null Luan Di   +5 more
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Coronal Magnetic Field Structure in Solar Active Regions

PLANETARY RADIO EMISSIONS VII, 2011
We analyzed the structure of the magnetic field in active regions at coronal altitudes, determined using multiwavelength observations of polarized radio emission in the microwave range at the radiotelescope RATAN-600. The observations were compared with the current-free magnetic field extrapolation of the photospheric field.
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Relation between the active region magnetic field and solar flares

Geomagnetism and Aeronomy, 2013
A weak active region (NOAA 11158) appeared on the solar disk near the eastern limb. This region increased rapidly and, having reached the magnetic flux higher than 1022 Mx, produced an X-class flare. Only weak field variations at individual points were observed during the flare.
A. I. Podgorny, I. M. Podgorny, N. S. Meshalkina   +2 more
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Magnetic field line topology in solar active regions

AIP Conference Proceedings, 1992
According to a recent study comparing magnetic fields extrapolated from photospheric measurements with chromospheric and coronal observations, the electric current helicity in active regions possesses a predominant sign in each of the two solar hemispheres.
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On the Magnetic Field Activity in Solar Active Regions

1991
In this short note a new method of analysis of the complexity and of the reactivity of ensembles of magnetic features in the solar active regions is proposed and briefly discussed.
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CONFIGURATION OF THE MAGNETIC FIELD IN SOLAR ACTIVE REGIONS

Solar Physics, 1997
In this paper we present the observational results of chromospheric and photospheric magnetograms in active regions obtained at the Huairou Solar Observing Station of the Beijing Astronomical Observatory. Simultaneous observations of the chromospheric and photospheric magnetic fields enable us to construct a possible configuration of the magnetic field
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Solar Active Region Coronal Magnetic Fields

Bulletin of the AAS, 2023
Dale Gary, Gelu Nita, Bin Chen, Stephen White, Timothy Bastian, Gregory Fleishman, Sijie Yu, Surajit Mondal, Pascal Saint-Hilaire, Thomas Y. Chen, Thomas Schad, Natsuha Kuroda   +11 more
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Influence of a solar active region on the interplanetary magnetic field

Solar Physics, 1968
Interplanetary magnetic field sectors evolution /1964-1965/, discussing solar active region development leading to magnetic loops in interplanetary ...
Kenneth H. Schatten, Norman F. Ness, John M. Wilcox   +2 more
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