The chemical composition of three planetary nebulae in the Magellanic clouds

Journal Article · Sat Jan 01 04:00:00 EST 1977 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/154904· OSTI ID:7130653

Dufour, R J; Killen, R M

Emission-line intensities in the planetary nebulae Henize 67 in the Small Magellanic Cloud (SMC) and Henize 97 and 153 in the LMC along with the small SMC H II regions Henize 9, 61, and 81 were measured from photographic image-tube spectra taken with the 1.5 m telescope at Cerro Tololo. The relative abundances of H, He, N, O, Ne, S, and Ar in the nebulae were estimated and compared with the compositions of galactic planetary nebulae and previously studied H II regions in the Clouds. The results show that (1) the N/O ratios in the planetary nebulae are substantially higher than found in the H II regions of each Cloud; (2) He/H approx. = 0.18 in the SMC planetary nebula, but seems normal (approx.0.10) in the two LMC planetaries; and (3) the compositions of the three small SMC H II regions are similar to that of larger SMC H II regions studied previously. It is concluded that the N/H values in the shells of planetary nebulae may not depend on the metal content of the progenitor star as much as recent theoretical models suggest and that the N content of the gas in the Magellanic Clouds arises primarily from sources other than planetary nebulae. (AIP)

• Research Organization: NASA L. B. Johnson Space Center, and Rice University
• OSTI ID: 7130653
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 211:1; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ARGON
CHEMICAL COMPOSITION
COSMIC RADIO SOURCES
CRYOGENIC FLUIDS
ELECTRON DENSITY
ELECTRON TEMPERATURE
ELEMENTS
EMISSION SPECTRA
FLUIDS
FUNCTIONS
GALAXIES
H2 REGIONS
HELIUM
HYDROGEN
MAGELLANIC CLOUDS
NEBULAE
NEON
NITROGEN
NONMETALS
OXYGEN
PLANETARY NEBULAE
RARE GASES
SPECTRA
SPECTRAL DENSITY
SPECTRAL FUNCTIONS
SULFUR