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Disappearing solar filaments and geomagnetic activity
Nature, 1982Early attempts to link solar filaments and their disappearances with geomagnetic activity1–7 were inconclusive. Joselyn and McIntosh8 have suggested that some magnetic storms are produced by disappearing filaments. However, we feel that their study included too few cases to establish this link conclusively because, of the 12 possible filament–storm ...
L. F. McNamara, C. S. Wright
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Large-scale motion of solar filaments
Journal of Astrophysics and Astronomy, 2000AbstractPrecise measurements of heliographic position of solar filaments were used for determination of the proper motion of solar filaments on the time-scale of days. The filaments have a tendency to make a shaking or waving of the external structure and to make a general movement of whole filament body, coinciding with the transport of the magnetic ...
Pavel Ambrož, Alfred Schroll
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Activity cycle of solar filaments
Journal of Astrophysics and Astronomy, 2007Long-term variation in the distribution of the solar filaments observed at the Observatorie de Paris, Section de Meudon from March 1919 to December 1989 is presented to compare with sunspot cycle and to study the periodicity in the filament activity, namely the periods of the coronal activity with the Morlet wavelet used.
K. J. Li +5 more
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Periodic Motion Along Solar Filaments
Solar Physics, 2006We present observations of four filaments that exhibit large-amplitude periodic mass motion. Observations are obtained using the high resolution (2″) and high cadence (1 min) Hα telescope system at the Big Bear Solar Observatory (BBSO). The motions found in these events are along the axis of the filaments, and are associated with the activity of a ...
Ju Jing +3 more
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1966
Abstract : A survey was made of the Lockheed solar patrol films in search of any parameters which could possible be linked with the occurrence of flares. High resolution observations ( or = 1 sec of arc) show that some filaments increase in darkness and become more sharply defined within several hours to several days before the onset of a flare ...
Sara F. Smith, Harry E. Ramsey
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Abstract : A survey was made of the Lockheed solar patrol films in search of any parameters which could possible be linked with the occurrence of flares. High resolution observations ( or = 1 sec of arc) show that some filaments increase in darkness and become more sharply defined within several hours to several days before the onset of a flare ...
Sara F. Smith, Harry E. Ramsey
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Failed Eruptions of Solar Filaments
Astronomy Reports, 2020Solar filaments (prominences), which suddenly and swiftly ascend, i.e., become eruptive, sometimes decelerate and stop at comparatively low altitudes. Causes of failed eruptions generally remain uncertain. The present study analyzes two eruptive phenomena with very similar initial geometries and configurations of external magnetic fields; one of these ...
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Solar Filaments and Photospheric Network
Solar Physics, 2005The locations of barbs of quiescent solar filaments are compared with the photospheric/chromospheric network, which thereby serves as a proxy of regions with enhanced concentrations of magnetic flux. The study covers quiet regions, where also the photospheric network as represented by flow converging regions, i.e., supergranular cell boundaries ...
Yong Lin +4 more
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Thin Threads of Solar Filaments
Solar Physics, 2005High-resolution images obtained in Hα with the new Swedish Solar Telescope at La Palma, Spain, have been used for studies of fine-scale threads in solar filaments. The widths of the thin threads are ≤0.3 arcsec. The fact that the width of the thinnest threads is comparable to the diffraction limit of the telescope of about 0.14 arcsec, at the ...
Yong Lin +4 more
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Differential rotation of solar filaments
Solar Physics, 1974The latitudinal component of solar differential rotation and the possibility of a radial component are discussed and compared to the observed rotational velocities of solar filaments. The author's values of rotational rate versus heliographic latitude for 100 points in the solar atmosphere derived from 17 quiescent filaments are shown to be comparable
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Activated solar filaments and flares
Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences, 1980Activations and disruptions of dark Ha filaments are very common phenomena on the Sun. They precede the most powerful two-ribbon solar flares, but they also appear far from any active region without any chromospheric flaring. Therefore, until very recently, filament disruptions were considered as interesting, but physically insignificant, flare ...
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