W Hya: molecular inventory by ISO-SWS

  title={W Hya: molecular inventory by ISO-SWS},
  author={K. Justtanont and Teije de Jong and A. Tielens and Helmut Feuchtgruber and L. B. F. M. Waters},
  journal={Astronomy and Astrophysics},
Infrared spectroscopy is a powerful tool to probe the inventory of solid state and molecular species in circumstellar ejecta. Here we analyse the infrared spectrum of the Asymptotic Giant Branch star W Hya, obtained by the Short and Long Wavelength Spectrometers on board of the Infrared Satellite Observatory. These spectra show evidence for the presence of amorphous silicates, aluminum oxide, and magnesium-iron oxide grains. We have modelled the spectral energy distribution using laboratory… 
Oxygen-rich AGB stars with optically thin dust envelopes
The dust composition and dynamics of the circumstellar envelopes of oxygen-rich AGB stars with low mass-loss rates (5 × 10 −8 -10 −5 Myr −1 ) have been investigated. We have analyzed the ISO-SWS
The wind of W Hydrae as seen by Herschel - II. The molecular envelope of W Hydrae
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The mid-infrared diameter of W Hydrae ,
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The wind of W Hydrae as seen by Herschel I. The CO envelope
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We present Odin observations of the AGB star W Hya in the ground-state transition of ortho-H2O, 110 − 101 ,a t 557 GHz. The line is clearly of circumstellar origin. Radiative transfer modelling of
Spectro-Imaging of the Asymmetric Inner Molecular and Dust Shell Region of the Mira Variable W Hya with MIDI/VLTI
We have observed W Hya, one of the closest and best-studied oxygen-rich evolved stars, in the dust sensitive mid-IR spectral domain with the interferometric instrument MIDI. Images could be obtained
On the detection of CO and mass-loss of bulge OH/IR stars
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Dust and molecular shells in asymptotic giant branch stars - Mid-infrared interferometric observations of R Aquilae, R Aquarii, R Hydrae, W Hydrae, and V Hydrae
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VLBA SiO observations of bright O-rich AGB stars
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By comparing IRAS mean colors and LRS spectral differences in a large sample of Mira variables with the chronological sequence for development of microwave maser emission among such stars, it appears
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Water and Dust Emission from W Hydrae
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Mass loss from OH/IR stars - Models for the infrared emission of circumstellar dust shells
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We have analyzed the 8 13:5 mU KIRT CGS3 spectra of 142 M-type stars including 80 oxygen- rich AGB stars and 62 red supergiants, with a view to understanding the dierences and similarities between
Sources of the 13 Microns Feature Associated with Oxygen-Rich Circumstellar Dust
A search of the database of spectra from the IRAS Low-Resolution Spectrometer has revealed 13 micron emission features in 187 sources, most of which are associated with stars embedded within
A subarcsecond H2O maser shell surrounding a variable star
Radio continuum and H{sub 2}O maser emission have been detected from the semiregular variable W Hya. The continuum emission at radio frequencies probably comes from the outer photosphere of the red
Full polarization structure of the OH main‐line maser envelopes of W Hydrae
Simultaneous MERLIN observations of the OH 1665- and 1667-MHz maser lines in the circumstellar envelope of the semiregular star W Hya have been taken in all Stokes parameters. The 1665-MHz emission
Modelling the dust and gas outflows from IRC+10 216 - I. Ground-based and airborne observations
We have developed a model for the dust and gas envelope of the C star IRC+10 216. Spherical symmetry is assumed, and the model consistently solves the full radiative transfer problem for the