Results 181 to 190 of about 12,394 (217)
Some of the next articles are maybe not open access.
Something about Red Supergiants
Proceedings of the International Astronomical Union, 2019AbstractI would like to present an overview of red supergiants (RSGs) in the Milky Way. There are only about 1400 objects listed as RSGs in the spectroscopic catalog by Skiff (2014); moreover, we are not sure yet about how they formed and where they formed.
openaire +1 more source
Giant and supergiant lattices on graphite
Physical Review B, 1993Anomalous giant lattices have been observed on four separate samples of highly oriented pyrolytic graphite with scanning tunneling microscopy. They exhibit hexagonal symmetry with lattice constants of 1.7, 2.8, 3.8, and 6.6 nm. Atomic resolution of graphite was obtained simultaneously. Kuwabara, Clarke, and Smith [Appl. Phys. Lett.
, Xhie, , Sattler, , Ge, , Venkateswaran
openaire +2 more sources
Publications of the Astronomical Society of the Pacific, 1982
Two extraordinary stars of type F and G are identified. These stars, HR 7008 and HD 174104, have strong lithium doublets. A detailed analysis shows each to have the cosmic abundance of lithium. It is argued that they are unmixed stars on the redward approach to the first giant branch.
openaire +1 more source
Two extraordinary stars of type F and G are identified. These stars, HR 7008 and HD 174104, have strong lithium doublets. A detailed analysis shows each to have the cosmic abundance of lithium. It is argued that they are unmixed stars on the redward approach to the first giant branch.
openaire +1 more source
Astrophysics and Space Science, 1968
The brightest star in either Magellanic cloud has been analyzed by the method of model atmospheres using observational data secured at Cerro Tololo. The results from abundance studies are in general accord with the conclusions by Przybylski. We find solar abundances for Fe, Sc, Mg, Si and, probably, Ca.
Gordon W. Wares +2 more
openaire +1 more source
The brightest star in either Magellanic cloud has been analyzed by the method of model atmospheres using observational data secured at Cerro Tololo. The results from abundance studies are in general accord with the conclusions by Przybylski. We find solar abundances for Fe, Sc, Mg, Si and, probably, Ca.
Gordon W. Wares +2 more
openaire +1 more source
1966
The early type supergiants are relatively easy to recognise because their absorption lines have a steep-sided blunt shape. The wings of the hydrogen lines are narrow and frequently an emission feature is seen at Hα in the spectra of the la supergiants.
openaire +1 more source
The early type supergiants are relatively easy to recognise because their absorption lines have a steep-sided blunt shape. The wings of the hydrogen lines are narrow and frequently an emission feature is seen at Hα in the spectra of the la supergiants.
openaire +1 more source
Variability of Supergiant Atmospheres
1980Many if not all supergiants show signs of variability, which is another indication of the instable character of these very extended atmospheres. Most of the variations are of a small amplitude and have a more or less erratic character, but a ‘ characteristic period’ is often detectable.
openaire +1 more source