Sulfur abundances in three halo planetary nebulae

Journal Article · Fri Jul 15 04:00:00 EDT 1983 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/161154· OSTI ID:5542448

Barker, T

The intensities of the (SIII) lambda9532 lines have been measured for the first time in the three known extreme halo planetary nebulae. Improved measurements have also been made of the (SII) lambda6717+lambda6731 lines. The S/H abundance ratios are (4.7 +- 6.8) x 10/sup -7/ for 108-76/sup 0/1, (1.4 +- 1.1) x 10/sup -7/ for K648, and (1.6 +- 1.1) x 10/sup -7/ for 49+88/sup 0/1. The S abundance in 108-76/sup 0/1 is too uncertain to draw any conclusions except that it is less than a tenth solar. The S abundances in the other two are approximately 1/100 of those in disk planetary nebulae and the Sun, consistent with the low Ar abundances also found in the halo planetary nebulae and with the Fe deficiency in the stars in M15, of which K648 is a member. Since the O and Ne abundances in the halo nebulae cover a wide range (nearly solar to 1/50 solar), the implication is that either the abundances of these elements have been enhanced by nuclear reactions in the planetary progenitors of S and Ar were synthesized galactically at a slower rate than O or Ne. In either case, it appears that S, like Ar, may be more representative of the true heavy-metal abundance in planetary nebulae than lighter elements like O and Ne.

• Research Organization: Department of Physics and Astronomy, Wheaton College
• OSTI ID: 5542448
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 270:2; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABUNDANCE
ARGON
ELEMENTS
FLUIDS
GASES
NEBULAE
NEON
NONMETALS
OXYGEN
PLANETARY NEBULAE
RARE GASES
SPECTRA
SULFUR
VISIBLE SPECTRA