2 00 2 the Massive Disk around Oh 231 . 8 + 4 . 2
نویسندگان
چکیده
We have obtained 11.7 µm and 17.9 µm images at the Keck I telescope of the circumstellar dust emission from OH 231.8+4.2, an evolved mass-losing red giant with a well studied bipolar outflow. We detect both a central unresolved point source with a diameter less than 0. ′′ 5 producing F ν (17.9 µm) = 60 Jy, and emission extended more than 1 ′′ away from the star which is aligned with the bipolar outflow seen on larger scales. We find that the unresolved central source can be explained by an opaque, flared disk with an outer radius of ∼5 × 10 15 cm and an outer temperature of ∼130 K. One possible model to explain this flaring is that the material in the disk is orbiting the central star and not simply undergoing a radial expansion.
منابع مشابه
High - resolution observations at λ = 3 mm of the OH 231 . 8 + 4 . 2 molecular outflow
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