SBS 1150+599A: an extremely oxygen-poor planetary nebula in the Galactic halo?
Abstract
We report results of a spectrophotometric study of SBS 1150+599A and discuss the nature of this object based upon our data. Our study shows that SBS 1150+599A is most probably a planetary nebula located in the Galactic halo and not a cataclysmic variable as originally proposed by the authors of the Second Byurakan Survey from low resolution spectroscopy. We have further elaborated on the properties of SBS 1150+599A (now becoming PN G135.9+55.9) with tools used for planetary nebula analysis. Our photoionization models show that, in order to match the observational constraints, the oxygen abundance in the nebula is probably extremely low, around 1/500 solar, which is one order of magnitude lower than the most oxygen-poor planetary nebulae known so far. This finding has strong implications on our understanding of the formation of planetary nebulae and of the evolution of the Galactic halo.
Cite
@article{arxiv.astro-ph/0104222,
title = {SBS 1150+599A: an extremely oxygen-poor planetary nebula in the Galactic halo?},
author = {G. Tovmassian and G. Stasinska and V. Chavushyan and S. Zharikov and C. Gutierrez and F. Prada},
journal= {arXiv preprint arXiv:astro-ph/0104222},
year = {2009}
}
Comments
13 pages, 5 figures, accepted for publication in Astronomy and Astrophysics