Results 11 to 20 of about 2,148 (181)
A Space Weather mission concept: Observatories of the Solar Corona and Active Regions (OSCAR) [PDF]
Journal of Space Weather and Space Climate, 2015 Coronal Mass Ejections (CMEs) and Corotating Interaction Regions (CIRs) are major sources of magnetic storms on Earth and are therefore considered to be the most dangerous space weather events. The Observatories of Solar Corona and Active Regions (OSCAR)
Strugarek Antoine +16 more
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The solar corona as an active medium for magnetoacoustic waves [PDF]
Plasma Physics and Controlled Fusion, 2021 Abstract The presence and interplay of continuous cooling and heating processes maintaining the corona of the Sun at the observed one million K temperature were recently understood to have crucial effects on the dynamics and stability of magnetoacoustic (MA) waves.
D Y Kolotkov +2 more
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Solar activity cycle and rotation of the corona [PDF]
Astronomy & Astrophysics, 2002 In this paper we consider the dependence of the coronal rotation period on solar activity. We analyzed the 10.7 cm radio emission flux covering cycles 19 to 22. We have established a new method for studying the rotation rate: by identifying the flux pulses with the recurrence of active longitudes.
Mouradian, Zadig +2 more
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Fundamental transverse vibrations of the active region solar corona [PDF]
Astronomy & Astrophysics, 2019 Context. Some high-resolution observations have revealed that the active region solar corona is filled with a myriad of thin strands even in apparently uniform regions with no resolved loops. This fine structure can host collective oscillations involving a large portion of the corona due to the coupling of the motions of the neighbouring strands. Aims.
Luna, M. +3 more
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THE EXPANSION OF ACTIVE REGIONS INTO THE EXTENDED SOLAR CORONA [PDF]
The Astrophysical Journal Supplement Series, 2013 Advanced image processing of Large Angle and Spectrometric Coronagraph Experiment (LASCO) C2 observations reveals the expansion of the active region closed field into the extended corona. The nested closed-loop systems are large, with an apparent latitudinal extent of 50 Degree-Sign , and expanding to heights of at least 12 R{sub Sun }.
Huw Morgan, Lauren Jeska, Drew Leonard
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Micro-events in the active and quiet solar corona [PDF]
Advances in Space Research, 2003 The content of hot material in the corona is not constant. Soft X-ray and high-temperature EUV line observations show that new material, apparently heated and evaporated from the chromosphere, is frequently injected into the corona both in active and quiet regions. Active regions are found to exhibit transient brightenings, termed here microflares, due
Benz, Arnold O., Grigis, Paolo C.
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On Stellar Coronae and Solar Active Regions
The Astrophysical Journal, 2000 Based on Yohkoh Soft X-Ray Telescope (SXT) observations of the Sun near peak activity level obtained on 1992 January 6, we search for coronal structures that have emission measure distributions EM(T ) that match the observed stellar coronal emission measure distributions derived for the intermediate-activity stars v Eri (K2 V) and m Boo A (G8 V) from ...
Jeremy J. Drake +4 more
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Extreme ultraviolet observations of active regions in the solar corona [PDF]
Symposium - International Astronomical Union, 1968 The coronal features associated with solar active regions can be observed by recording images of the Sun at extreme ultraviolet (XUV) wavelengths. Pinhole cameras have been flown on stabilized sun-pointing ‘Skylark’ rockets to obtain broad-waveband XUV solar images.
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Self-Similar Signature of the Active Solar Corona within the Inertial Range of Solar-Wind Turbulence [PDF]
Physical Review Letters, 2007 We quantify the scaling of magnetic energy density in the inertial range of solar wind turbulence seen in-situ at 1AU with respect to solar activity. At solar maximum, when the coronal magnetic field is dynamic and topologically complex, we find self-similar scaling in the solar wind, whereas at solar mimimum, when the coronal fields are more ordered ...
Kiyani, K. +3 more
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Statistical Properties of Magnetic Activity in the Solar Corona
The Astrophysical Journal, 1998 The long-time statistical behavior of a two-dimensional section of a coronal loop subject to random magnetic forcing is presented. The highly intermittent nature of dissipation is revealed by means of magnetohydrodynamic (MHD) turbulence numerical simulations. Even with a moderate magnetic Reynolds number, intermittency is clearly present in both space
GEORGOULIS M. +2 more
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