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Abundance Anomalies in the X-ray Spectra of the Planetary Nebulae NGC 7027 and BD +30 363

Holly L. Maness·Saeqa D. Vrtilek·Noam Soker·Joel H. Kastner
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Abstract

We revisit Chandra observations of the planetary nebulae NGC 7027 and BD +30 3639 in order to address the question of abundance anomalies in the X-ray emitting gas. Enhanced abundances relative to solar of magnesium (Mg) for NGC 7027 and neon (Ne) for BD +30 3639 are required to fit their X-ray spectra, whereas observations at optical and infrared wavelengths show depleted Mg and Ne in these systems. We attribute the enhancement of Mg in NGC 7027 in the X-ray, relative to the optical, to the depletion of Mg onto dust grains within the optical nebula. For BD +30 3639, we speculate that the highly enhanced Ne comes from a WD companion, which accreted a fraction of the wind blown by the asymptotic giant branch progenitor, and went through a nova-like outburst which enriched the X-ray emitting gas with Ne.

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Holly L. Maness, Saeqa D. Vrtilek, Noam Soker, Joel H. Kastner. 2003-01-30. Abundance Anomalies in the X-ray Spectra of the Planetary Nebulae NGC 7027 and BD +30 363. https://doi.org/10.1086/374414

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