Now showing items 11-20 of 22
Soft solar X-rays and solar activity
(Kluwer Academic Publishers; D. Reidel Publishing Company ; Springer Science+Business Media, 1971-09)
Soft solar X-rays in the wavelength interval 8–12 Å were observed from OSO III. The totality of the observations that were made between 9 March, 1967, and 18 May, 1968, is summarized graphically and compared to the course ...
Two-dimensional spatial power spectra of photospheric velocity fluctuations
(Kluwer Academic Publishers; D. Reidel Publishing Company ; Springer Science+Business Media, 1974-03)
Two-dimensional spatial autocorrelation functions and power spectral density distributions were obtained from high-resolution velocity spectroheliograms. Although the autocorrelation functions indicate the existence of ...
Characterististics of plage fragments with photospheric network properties
(Kluwer Academic Publishers; D. Reidel Publishing Company ; Springer Science+Business Media, 1980-08)
Using data taken with the multi-channel magnetograph at KPNO, we demonstrate that plage regions surrounding a sunspot have thermal properties found in the photospheric network. These network-like regions existed up to the ...
Observations of the infrared triplet of singly ionized calcium
(Kluwer Academic Publishers; D. Reidel Publishing Company ; Springer Science+Business Media, 1970-03)
Observations are presented of the Ca ii infrared triplet (8498 Å, 8542 Å, and 8662 Å) at three positions on the solar disk to make possible direct analyses of the lines and comparisons with theoretical computations. The ...
Dependence of the correlation of small scale photospheric structures upon resolution
(Kluwer Academic Publishers; D. Reidel Publishing Company ; Springer Science+Business Media, 1979-06)
Correlations between continuum intensity, velocity, and equivalent widths of two Mn i lines as observed with two different entrance apertures tend to deteriorate with improvement in spatial resolution. The KPNO multichannel ...
Photospheric network from study of manganese lines
(Kluwer Academic Publishers; D. Reidel Publishing Company ; Springer Science+Business Media, 1978-10)
Area scans with the multi-channel magnetograph at the Kitt Peak McMath Telescope provided simultaneous measures of equivalent widths in two Mn lines, continuum intensity and longitudinal magnetic field component. Observations ...
Protostellar Disk Formation and Early Evolution
(Kluwer Academic Publishers; Springer Science+Business Media, 2000-03)
This contribution describes the formation of circumstellar disks and their earliest evolutionary phases when self-gravity in the disk plays a crucial role in eliciting the transport of mass and angular momentum. We first ...
On the Abundance of Holmium in the sun
(Kluwer Academic Publishers; Springer Science+Business Media, 2002-12)
The abundance of holmium ( Z =67) in the Sun remains uncertain. The photospheric abundance, based on lines of Ho ii, has been reported as + 0.26±0.16 (on the usual scale where log(H) = 12.00), while the meteoritic value ...
Soft solar X-rays and solar activity
(Kluwer Academic Publishers; D. Reidel Publishing Company ; Springer Science+Business Media, 1971-12)
Minor Hα activity, consisting of small brightenings and small, surgelike spikes, was observed to take place above an active center at the solar limb in good time-association with small fluctuations in the soft X-ray ...
Solar soft X-rays and solar activity
(Kluwer Academic Publishers; D. Reidel Publishing Company ; Springer Science+Business Media, 1971-02)
Flare-associated soft X-ray bursts (8–12 Å) are examined for 283 events observed by OSO-III. These bursts are shown to be predominantly thermal in nature. Their time-profiles are roughly similar to those of the associated ...