The first water fountain in a planetary nebula
نویسندگان
چکیده
منابع مشابه
ALMA Observations of the Water Fountain Pre-Planetary Nebula IRAS 16342-3814: High-Velocity Bipolar Jets and an Expanding Torus.
We have mapped 12CO J=3-2 and other molecular lines from the "water-fountain" bipolar pre-planetary nebula (PPN) IRAS 16342-3814 with [Formula: see text] resolution using ALMA. We find (i) two very high-speed knotty, jet-like molecular outflows, (ii) a central high-density (> few × 106 cm-3), expanding torus of diameter 1300 AU, and (iii) the circumstellar envelope of the progenitor AGB, genera...
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Context. Water fountain stars are very young post-AGB stars with high velocity water maser jets. They are the best objects to study the onset of bipolar jets from evolved stars due to their young dynamical ages. However, none of them have been observed in any thermal lines. Aims. Search for CO lines in the water fountain star IRAS 16342-3814 and investigate the properties of its thermal gas. Me...
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ژورنال
عنوان ژورنال: Proceedings of the International Astronomical Union
سال: 2012
ISSN: 1743-9213,1743-9221
DOI: 10.1017/s1743921312007016