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Hot Molecular Gas in the Central 10 Parsecs of the Galaxy

Robeson M. Herrnstein·Paul T. P. Ho
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Abstract

We present results from observations of NH_3(1,1), (2,2), (3,3), and (6,6) with the Very Large Array. The data sample the inner 10 pc (4') of the Galaxy and have a velocity coverage of -140 to +130 km/s. The velocity integrated NH_3(3,3) image shows that the Sgr A East supernova remnant is impacting the 50 km/s GMC in the northeast, the northern ridge in the north, and the western streamer in the west. These results imply that the Sgr A East has a large effect on the molecular environment near Sgr A* and may be pushing much of the molecular gas away from Sgr A*. The physical properties of the western streamer and its relation to Sgr A East are discussed in detail. We also summarize the detection of hot molecular gas less than 2 pc from Sgr A* in projected distance. This gas is seen only in NH_3(6,6) and has line widths of 75-85 km/s, indicating that it is physically close to the nucleus.

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Robeson M. Herrnstein, Paul T. P. Ho. 2003-03-06. Hot Molecular Gas in the Central 10 Parsecs of the Galaxy. https://doi.org/10.1002/asna.200385049

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