The Collimated Wind in Ngc 253
نویسنده
چکیده
Received ; accepted – 2 – ABSTRACT Near-infrared Fabry-Perot imaging has revealed H 2 emission extended to about 130 pc from the disk of NGC 253. It is closely related to the hot plasma observed in soft X-rays: filamentary H 2 features are found at the edges of the hot plasma. These are the places of direct interaction between a superwind and its surrounding molecular gas. We suggest that the filamentary features actually trace a more or less conical shell-like structure, whose tangential line of sight to us is intensely observed. The H 2 emission shell is most likely from the molecular gas blown out or swept to the side by the hot plasma outflow. Dust is associated with this molecular gas structure. The outflow is tilted with respect to the disk, possibly suggesting the inhomogeneous nature of the interstellar medium in which the starburst takes place.
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