%A"Torres-Peimbert, S" %A"Rayo, J F" %A"Peimbert, M [Universidad Nacional Autonoma de Mexico, Mexico City. Inst. de Astronomia]" %D1981 %I; %2 %J[] %K71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS, PLANETARY NEBULAE, CHEMICAL COMPOSITION, CARBON IONS, EMISSION SPECTRA, EXPERIMENTAL DATA, GALACTIC EVOLUTION, HELIUM IONS, HYDROGEN IONS, NEON IONS, NITROGEN IONS, OXYGEN IONS, SPECTROPHOTOMETRY, STELLAR ATMOSPHERES, ATMOSPHERES, CHARGED PARTICLES, DATA, INFORMATION, IONS, NEBULAE, NUMERICAL DATA, SPECTRA, 640105* - Astrophysics & Cosmology- Galaxies %PMedium: X; Size: Pages: 315-319 %TChemical enrichment in halo planetary nebulae %XPhotoelectric spectrophotometry of emission lines in the 3400-7400 A region is presented for the planetary nebulae 108-76/sup 0/1(BB1). From these observations the relative abundances of H, He, C, N, O and Ne are derived. The abundances of the halo PN (BB1, H4-1 and K648) are compared to those predicted by stellar evolution theory under the assumption that the envelope has the chemical composition of the matter located between the H burning shell and the surface. The observed He/H and C/O values are higher than predicted which implies that halo PN contain matter from deeper layers than the H burning shell. Furthermore, the O/Ar, N/Ar and Ne/Ar values in halo PN are higher than in the solar neighbourhood, at least part of this enrichment is produced by the PN progenitors. %0Conference %N;Journal ID: CODEN: RMAAD %1 %CMexico %Rhttps://doi.org/ Journal ID: CODEN: RMAAD HEDB %GEnglish