2013ApJ...770...44L

We present the Submillimeter Array 157 pointing mosaic in 0.86 mm dust continuum emission with 5.''1x4.''2 angular resolution, and the National Radio Astronomy Observatory Green Bank 100 m Telescope (GBT) observations of the CS/C³⁴S/¹³CS 1-0 and SiO 1-0 emission with ≤ 20''x18'' angular resolution. The dust continuum image marginally resolves at least several tens of 10-10² M_☉ dense clumps in the 5' field including the circumnuclear disk (CND) and the exterior gas streamers. There is very good agreement between the high resolution dust continuum map of the CND and all previous molecular line observations. As the dust emission is the most reliable optically thin tracer of the mass, free from most chemical and excitation effects, we demonstrate the reality of the abundant localized structures within the CND, and their connection to external gas structures. From the spectral line data, the velocity dispersions of the dense clumps and their parent molecular clouds are ∼10-20 times higher than their virial velocity dispersions. This supports the idea that the CND and its immediate environment may not be stationary or stable structures. Some of the dense gas clumps are associated with 22 GHz water masers and 36.2 GHz and 44.1 GHz CH₃OH masers. However, we do not find clumps that are bound by the gravity of the enclosed molecular gas. Hence, the CH₃ OH or H₂O maser emission may be due to strong (proto)stellar feedback, which may be dispersing some of the gas clumps.