Spectrum and chemical composition of the remarkable planetary nebula NGC 6537.

Abstract:

:Observations with the image tube scanner at the Shane 3-m telescope are combined with data obtained with the International Ultraviolet Explorer to assess the spectrum of the remarkable high-excitation planetary nebula NGC 6537. We have analyzed the spectrum of this nitrogen-rich object with the aid of the theoretical nebular models. The models permit one to estimate the fraction of unobservable ions of abundant elements. On the scale log N(H) = 12, the logarithmic abundance values for He, C, N, and O are as follows: [Table: see text] The abundances of Ne S, Cl, and Ar appear to be essentially solar to within a factor of 2. Our interpretation is that the progenitor of NGC 6537 had a chemical composition not differing greatly from that of the Sun. In the course of its prenebular evolution, C and probably O were converted to N and much H was converted to helium.

authors

Feibelman W,Aller LH,Keyes CD,Czyzak SJ

doi

10.1073/pnas.82.8.2202

subject

Has Abstract

pub_date

1985-04-01 00:00:00

pages

2202-6

issue

8

eissn

0027-8424

issn

1091-6490

journal_volume

82

pub_type

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