Results 151 to 160 of about 1,306 (183)

Solar EUV and UV Emission Line Observations Above a Polar Coronal Hole

Space Science Reviews, 1998
The roll manoeuvre of SOHO on September 3, 1997 provided the opportunity to study the northern coronal hole with SUMER slits in east-west orientation, so that polar plumes and inter-plume lanes could be observed simultaneously. A preliminary analysis of the observations shows that lines emitted by ions with the lowest formation temperatures (with the ...
Wilhelm, K., Bodmer, R.
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The identification of new forbidden coronal lines in the solar EUV spectrum

Solar Physics, 1971
Identifications are proposed for twenty of the twenty-eight coronal lines observed in the spectra obtained during a rocket flight into the path of the 7 March, 1970 solar eclipse. The methods by which the lines have been identified are discussed. Most of the lines identified are from forbidden transitions between levels in the ground 2pn and 3pn ...
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Line-Tying Effects on Stability and Heating of Solar Coronal Loops

1991
The effect of line-tying of solar coronal loops on both stability and heating by means of resonant absorption of Alfven waves is investigated numerically. It is shown that line-tying alone is not stabilizing, whereas the joint effect of line-tying and neighbouring flux tubes may stabilize a coronal loop.
G. Halberstadt, J. P. Goedbloed, S. M. Poedts, R. A. M. Van der Linden   +3 more
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Improved solar coronal temperature for equal green and red line intensities

Solar Physics, 1976
An improved value of the temperature in the solar corona for equal green and red line intensities is obtained. This temperature is in better agreement with a quoted line-width value than the previous theoretical ones.
Udit Narain, Suresh Chandra
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Discrepancies between calculated and observed Fexvii and Nixix solar coronal lines

Astrophysics and Space Science, 1975
We extend the 36-levels model atom Fe+16 of Loulergue and Nussbaumer (1973) to a 51-levels atom includingn=4 configuration. Our earlier conclusion that relative intensities among the Fexvii lines are not sufficiently sensitive to variations in electron densities and electron temperature to deduce these parameters from observed intensity ratios still ...
M. Loulergue, H. Nussbaumer
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The solar coronal green line as an index of cosmic ray modulation

Planetary and Space Science, 1973
Abstract In recent years several papers have indicated that the solar coronal green line emission (λ=5303A) is the ‘best’ indicator of cosmic ray modulation. This paper questions this result for the following reasons: (a) the problems of green line measurement obscure the true meaning of the resulting observations; (b) there is a lack of any direct ...
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Spectroscopic studies of solar corona VI: Trend in line-width variation of coronal emission lines with height independent of the structure of coronal loops

Journal of Astrophysics and Astronomy, 2006
We have obtained spectroscopic observations in coronal emission lines by choosing two lines simultaneously, one [Fe x] 6374 A and the other [Fe xi] 7892 A or [Fe xiii] 10747 A or [Fe xiv] 5303 A. We found that in 95 per cent of the coronal loops observed in 6374 A, the FWHM of the emission line increases with height above the limb irrespective of the ...
Jagdev Singh, Takashi Sakurai, Kiyoshi Ichimoto, S. Muneer   +3 more
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Coronal Emission Lines observed at the Total Solar Eclipse of June 19, 1936

Nature, 1937
THE unusual brightness of the corona at the 1936 total eclipse—it was easily seen several seconds before totality began—has given Prof. Sekiguti and his colleagues the chance of obtaining some new lines in the emission spectrum of the corona. Confirming Prof. Tanaka, he restores the line at 4725 A., previously rejected as being insufficiently supported,
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On the Solar Coronal Lines at the Total Eclipse in 1943

Journal of the Physical Society of Japan, 1950
Tutomu Tanaka, Hirobumi Oura
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Coronal emission line profile observations at total solar eclipses

Solar Physics, 1975
D. H. Liebenberg, R. J. Bessey, B. Watson   +2 more
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