Skip to main content
Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1983 Mar;80(6):1764–1766. doi: 10.1073/pnas.80.6.1764

Magellanic cloud planetary nebula with suspected strong forbidden iron lines

L H Aller *, S J Czyzak
PMCID: PMC393685  PMID: 16593294

Abstract

The relatively high-excitation nebula (Westerlund-Smith object 25) in the large Magellanic cloud shows prominent forbidden lines of [Ar IV], the close [Ne IV] pair λ4724, 4726, [Ca V] λ5309, [Fe V] λ4227, and probably [Fe VI] and [Fe VII], as well. A conventional interpretation of observations secured with a vidicon detector at the Cerro Tololo 4-m telescopes indicates an essentially “normal” helium abundance but depletions of N, O, Ne, and other elements with respect to our own galaxy. When a comparison is made with diffuse nebulae or H II regions in the large Magellanic cloud, we find helium to be more abundant, oxygen to be depleted, and nitrogen, neon, and argon to be comparable. The abundance of sulfur is uncertain. Iron in the gaseous phase is certainly more plentiful than in conventional planetaries.

Keywords: gaseous nebulae, galaxies

Full text

PDF
1764

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Aller L. H., Keyes C. D., Czyzak S. J. Model nebulae and determination of the chemical composition of the Magellanic Clouds. Proc Natl Acad Sci U S A. 1979 Apr;76(4):1525–1528. doi: 10.1073/pnas.76.4.1525. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Wilkinson P. C., Haston W. S., Shields J. M. Some determinants of the locomotory behaviour of phagocytes and lymphocytes in vitro. Clin Exp Immunol. 1982 Dec;50(3):461–473. [PMC free article] [PubMed] [Google Scholar]

Articles from Proceedings of the National Academy of Sciences of the United States of America are provided here courtesy of National Academy of Sciences

RESOURCES