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We used the CSO 10.4 meter telescope to image the 350 micron and 450 microncontinuum and CO J=6-5 line emission of the IRAS 20126+4104 clump. Thecontinuum and line observations show that the clump is isolated over a 4 pcregion and has a radius of ~ 0.5 pc. Our analysis shows that the clump has aradial density profile propto r ^{-1.2} for r <~ 0.1 pc and has propto r^{-2.3}for r >~ 0.1 pc which suggests the inner region is infalling, while the infallwave has not yet reached the outer region. Assuming temperature gradient ofr^{-0.35}, the power law indices become propto r ^{-0.9} for r < ~0.1 pc andpropto r^{-2.0} for r >~ 0.1 pc. Based on a map of the flux ratio of350micron/450micron, we identify three distinct regions: a bipolar feature thatcoincides with the large scale CO bipolar outflow; a cocoon-like region thatencases the bipolar feature and has a warm surface; and a cold layer outside ofthe cocoon region. The complex patterns of the flux ratio map indicates thatthe clump is no longer uniform in terms of temperature as well as dustproperties. The CO emission near the systemic velocity traces the dense clumpand the outer layer of the clump shows narrow line widths (< ~3 km/s). Theclump has a velocity gradient of ~ 2 km/s pc^{-1}, which we interpret as due torotation of the clump, as the equilibrium mass (~ 200 Msun) is comparable tothe LTE mass obtained from the CO line. Over a scale of ~ 1 pc, the clumprotates in the opposite sense with respect to the >~ 0.03 pc disk associatedwith the (proto)star. This is one of four objects in high-mass and low-massstar forming regions for which a discrepancy between the rotation sense of theenvelope and the core has been found, suggesting that such a complex kinematicsmay not be unusual in star forming regions.

Submillimeter Observations of The Isolated Massive Dense Clump IRAS 20126+4104