H2O Maser Observations of Candidate Post-AGB Stars and Discovery of Three High-velocity Water Sources
arXiv:astro-ph/0702086 · doi:10.1086/511383
Abstract
We present the results of 22 GHz H_2O maser observations of a sample of 85 post-Asymptotic Giant Branch (post-AGB) candidate stars, selected on the basis of their OH 1612 MHz maser and far-infrared properties. All sources were observed with the Tidbinbilla 70-m radio telescope and 21 detections were made. 86 GHz SiO Mopra observations of a subset of the sample are also presented. Of the 21 H_2O detections, 15 are from sources that are likely to be massive AGB stars and most of these show typical, regular H_2O maser profiles. In contrast, nearly all the detections of more evolved stars exhibited high-velocity H_2O maser emission. Of the five sources seen, v223 (W43A, IRAS 18450-0148) is a well known `water-fountain' source which belongs to a small group of post-AGB stars with highly collimated, high-velocity H_2O maser emission. A second source in our sample, v270 (IRAS 18596+0315), is also known to have high-velocity emission. We report the discovery of similar emission from a further three sources, d46 (IRAS 15445-5449), d62 (IRAS 15544-5332) and b292 (IRAS 18043-2116). The source d46 is an evolved post-AGB star with highly unusual maser properties. The H_2O maser emission from d62 is probably associated with a massive star. The source b292 is a young post-AGB star that is highly likely to be a water-fountain source, with masers detected over a velocity range of 210 km s^{-1}.
47 pages, 9 figures, 4 tables, accepted by ApJ
References in corpus (22)
- Keplerian discs around post-AGB stars: a common phenomenon?
- Dynamos in Asymptotic-Giant-Branch Stars As the Origin of Magnetic Fields Shaping Planetary Nebulale
- A magnetically collimated jet from an evolved star
- Bipolar outflows in OH/IR stars
- A movie of a star: multi-epoch VLBA imaging of the SiO masers towards the Mira variable TX Cam
- The ATCA/VLA OH 1612 MHz survey. III. Northern Galactic Plane
- Interstellar Hydroxyl Masers in the Galaxy. II. Zeeman Pairs and the Galactic Magnetic Field
- From the Owl to the Eskimo: the Radiation-Gasdynamics of Planetary Nebulae IV
- Disk Formation by AGB Winds in Dipole Magnetic Fields
- Application of MHD Disk Wind Solutions to Planetary/Protoplanetary Nebulae
- Sub-au imaging of water vapour clouds around four Asymptotic Giant Branch stars
- Collimated Fast Winds in Wide Binary Progenitors of Planetary Nebulae
- OH-selected AGB and post-AGB objects I.Infrared and maser properties
- Turbulent Dynamo in Asymptotic Giant Branch Stars
- A survey for water maser emission towards planetary nebulae. New detection in IRAS 17347-3139
- OH Maser Observations of Planetary Nebulae Precursors
- OH 12.8-0.9: A New Water-Fountain Source
- The spectral evolution of post-AGB stars
- OH-selected AGB and post-AGB stellar objects II.Blue versus red evolution off the AGB
- A shock-excited OH maser in a post-AGB envelope ?
- Detections of SiO and HO Masers in the Bipolar Nebula IRAS 19312+1950
- Radio observations of the planetary nebula around the OH/IR Star OH354.88-0.54 (V1018 Sco)
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- The spatio-kinematical structure and distance of the pre-planetary nebula IRAS 19134+2131
- OH maser emission in the THOR survey of the northern Milky Way
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- The Motion of Water Masers in the Pre-Planetary Nebula IRAS 16342-3814
- Radio interferometric observations of candidate water-maser-emitting planetary nebulae
- VLA observations of the "water fountain" IRAS 16552-3050
- An updated catalog of OH-maser-emitting planetary nebulae
- Stellar molecular jets traced by maser emission
- Water maser detections in southern candidates to post-AGB stars and Planetary Nebulae
- Water Maser Survey on AKARI and IRAS Sources: A Search for "Low-Velocity" Water Fountains
- Identification of Very Red Counterparts of SiO Maser and OH/IR Objects in the GLIMPSE Survey
- H2O Maser Polarization of the Water Fountains IRAS 15445-5449 and IRAS 18043-2116
- A Survey for Hydroxyl in the THOR Pilot Region around W43
- The 6-GHz multibeam maser survey III: comparison between the MMB and HOPS
- Accurate OH Maser Positions From The SPLASH Survey III: The Final 96 Square Degrees
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- Maser and Infrared Studies of Oxygen-Rich Late/Post-AGB Stars and Water Fountains: Development of a New Identification Method
- Sensitive CO and 13CO survey of water fountain stars. Detections towards IRAS 18460-0151 and IRAS 18596+0315
- Interferometric confirmation of "water fountain" candidates
- CO J=3-2 Emission from the "Water Fountain" Sources IRAS 16342-3814 and IRAS 18286-0959
- Extremely Strong ^{13}CO J=3-2 Line in the "Water Fountain" IRAS 16342-3814: Evidence for the Hot-Bottom Burning
- Study of extremely reddened AGB stars in the Galactic bulge
- A search for water maser emission toward obscured post-AGB star and planetary nebula candidates
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- Subarcsecond Imaging of the High-Mass Star Forming Region Onsala 1
- Do Water Fountain Jets Really Indicate the Onset of the Morphological Metamorphosis of Circumstellar Envelopes?
- Deep into the Water Fountains: The case of IRAS 18043-2116
- Evolution of the outflow in the water fountain source IRAS 180432116
- Searching for nascent planetary nebulae: OHPNe candidates in the SPLASH survey
- SCOTCH -- Search for Clandestine Optically Thick Compact HIIs
- Maser emission during post-AGB evolution
- Probing the fast outflow in IRAS 15452-5459 with ATCA observations of OH, H2O, and SiO masers
- CO observations of water-maser post-AGB stars and detection of a high-velocity outflow in IRAS 15452-5459
- Exciting Maser Science with New Instruments - the Promise of the EVLA