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Radio Photosphere and Mass-Loss Envelope of VY CMa

S. J. Lipscy·M. Jura·M. J. Reid
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Abstract

We have used the VLA to detect emission from the supergiant VY CMa at radio wavelengths and have constructed 3000-4500 K isothermal outer atmospheres constrained by the data. These models produce a radio photosphere at 1.5-2 R_ast. An extrapolation of the model can account for the observed total mass-loss rate of the star. We also present mid-infrared imaging of the supergiant that suggests warm dust is extended in the same direction as the near-infrared reflection nebula around VY CMa. The origin of the asymmetries in the outflow remains an unsolved problem.

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S. J. Lipscy, M. Jura, M. J. Reid. 2005-02-28. Radio Photosphere and Mass-Loss Envelope of VY CMa. https://doi.org/10.1086/429900

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