The “21” μm and “30” μm Emission Features in Planetary Nebulae with Wolf-Rayet Central Stars
نویسندگان
چکیده
منابع مشابه
The discovery of the “ 21 ” μ m and “ 30 ” μ m emission features in Planetary Nebulae with Wolf - Rayet central stars ⋆
The discovery of the " 21 " µm and " 30 " µm emission features in Planetary Nebulae with Wolf-Rayet central stars ⋆ Abstract. We report the discovery of the " 21 " µm and " 30 " µm features in the planetary nebulae around the hydrogen-deficient stars HD 826 and HD 158269. The carriers of these features are known to be produced in outflows around carbon-rich stars. This discovery demonstrates th...
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We present spectra of 32 previously unpublished confirmed and candidate Wolf-Rayet ([WR]) and weak emission-line (WELS) central stars of planetary nebulae (CSPNe). Eighteen stars have been discovered in the Macquarie/AAO/Strasbourg Hα (MASH) PN survey sample, and we have also uncovered 14 confirmed and candidate [WR]s and WELS among the CSPNe of previously known PNe. Spectral classifications ha...
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Spatially resolved long-slit spectrophotometric data for the planetary nebulae PB 6, NGC 2452, NGC 2867, NGC 6905 and He 2-55 are presented. Different knots were observed in each nebula. All the nebulae are ionized by [WC 2–3] type nuclei. For the five objects, we calculated photoionization models using the ionizing radiation field from models of expanding atmospheres. The photoionization model...
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ژورنال
عنوان ژورنال: Symposium - International Astronomical Union
سال: 2003
ISSN: 0074-1809
DOI: 10.1017/s0074180900208802