Lyman Continuum Optical Depths of Planetary Nebulae.
نویسندگان
چکیده
منابع مشابه
Optical Coordinates of Southern Planetary Nebulae
A homogeneous set of new measurements of nearly all (995 out of 1007) objects from the Strasbourg-ESO Catalogue of Galactic Planetary Nebulae or in the first supplement of this catalogue in the area covered by the DENIS survey (δ < +2) is given here. A list of 24 new and 27 wrong crossidentifications with sources in the IRAS PSC catalogue and some confusion in the literature is listed as well.
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Five planetary nebulae are known to show hydrogen-poor material near the central star. In the case of A58, this gas was ejected following a late thermal pulse similar to Sakurai. In this paper I will review these five objects. One of them, IRAS 18333−2357, may not be a true PN. I will show that there is a strong case for a relation to the [WC] stars and their relatives, the weak emission-line s...
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ژورنال
عنوان ژورنال: The Astronomical Journal
سال: 1965
ISSN: 0004-6256
DOI: 10.1086/109791