Results 181 to 190 of about 10,692 (216)

Coronal holes as sources of solar wind

Solar Physics, 1976
We investigate the association of high-speed solar wind with coronal holes during the Skylab mission by: (1) direct comparison of solar wind and coronal X-ray data; (2) comparison of near-equatorial coronal hole area with maximum solar wind velocity in the associated streams; and (3) examination of the correlation between solar and interplanetary ...
J. T. Nolte, A. S. Krieger, A. F. Timothy, R. E. Gold, E. C. Roelof, G. Vaiana, A. J. Lazarus, J. D. Sullivan, P. S. McIntosh   +8 more
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Coronal holes and solar magnetic fields

Space Science Reviews, 1979
Since 1972, nearly continuous observations of coronal holes and their associated photospheric magnetic fields have been made using a variety of satellite and ground-based equipment. The results of comparisons of these observations are reviewed and it is demonstrated that the structure and evolution of coronal holes is basically governed by the large ...
John W. Harvey, Neil R. Sheeley
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Solar structures related to coronal holes

Astronomy Reports, 2007
The nature of structures detected recently on the Sun in soft X rays by I.F. Nikulin (Sternberg Astronomical Institute) and called by him “partings” is discussed. It is shown that these structures are sign-reversal lines for the normal component of the curvature vector of the magnetic lines.
M. M. Molodenskiĭ, L. I. Starkova
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Alfvén waves in the solar polar coronal holes

AIP Conference Proceedings, 1999
We study the variation of the line width and electron density as a function of height above two coronal holes from forbidden spectral lines of Si VIII. The spectra were obtained with the Solar Ultraviolet Measurements of Emitted Radiation spectrometer flown on the Solar and Heliospheric Observatory spacecraft.
Banerjee, D., Teriaca, L., Doyle, J., Wilhelm, K.   +3 more
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Peculiar Features in the Solar Coronal Hole Occurrence

Solar Physics, 2002
A good knowledge of coronal hole (CH) evolution in time is relevant for the understanding of the decay and/or the stability of large-scale magnetic fields in the different heliographic latitudinal belts. Using a CH catalogue, mainly compiled from the He I line (10830 Å) measurement (Sanchez-Ibarra and Barraza-Paredes, 1992, and updated from the NOAA ...
Hofer M.Y., Storini M.
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Low-latitude coronal holes during solar maximum

Advances in Space Research, 2004
Abstract The Ultraviolet Coronagraph Spectrometer (UVCS) on SOHO has been used to observe large low-latitude coronal holes during solar maximum that produced fast solar wind streams. UVCS observations show that large low-latitude coronal holes at solar maximum, coronal holes of at least 10° in longitude, have plasma properties that seem to bridge the
M.P. Miralles, S.R. Cranmer, J.L. Kohl
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Energetics of Solar Coronal Holes

1991
We examine the energetics of a solar coronal hole in the framework of magnetohydrodynamics (MHD). Given typical values of the observed parameters, it is estimated that the Poynting flux maintained by the solar rotation and a trailing magnetic field is potentially capable of driving and heating a wind stream in a coronal hole region.
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Polar coronal holes and solar cycles

Solar Physics, 1979
The relationship between the geomagnetic activity of the three years preceding a sunspot minimum and the peak of the next sunspot maximum confirms the polar origin of the solar wind during one part of the solar cycle. Pointing out that the polar holes have a very small size or disappear at the time of the polar field reversal, we suggest a low latitude
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Models for Solar Coronal Holes.

1978
Abstract : This report summarizes several investigations of coronal holes and quiet regions. Temperature-density models for those regions have been derived from EUV observations. It is found that the coronal temperature, density, and temperature gradient are lower in coronal holes than in quiet regions.
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Investigation of Solar Rotation Using Coronal Holes

Astrophysics, 2015
The rotation of the solar coronal holes was studied. Data from the Kitt Peak Observatory in the line 10830 A He I for 2003—2012 was used for this purpose. The rotation of 434 coronal holes in the latitude interval ±40° was studied. The maximum angular velocity is observed at latitudes ±15°.
D. R. Japaridze, S. R. Bagashvili, B. M. Shergelasvili, B. B. Chargeishvili   +3 more
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