Submillimeter continuum survey of the Galactic center

We have conducted a survey of the 800 micron continuum emission from an approximately 1.5 deg x 0.2 deg area around the Galactic center with the objective to study the distribution of high-density material in the nuclear disk and to investigate the contribution of high-mass star formation to the luminosity and ionization of this region. Toward known high-mass star-forming regions, such as Sgr B2 and Sgr C, the large-scale distribution of the submillimeter continuum emission, which traces the temperature-weighted column density of dust, correlates well with the distribution of the radio continuum and far-infrared emission. However, in the Sgr A complex and the vicinity of the radio arc the correlation between the distribution of Giant Molecular Clouds (GMC) cores traced by the dust emission and those of compact far-infrared sources and compact H II regions is poor. This may indicate that many of the dust cores detected in our survey are heated by the diffuse external radiation field rather than embedded young stars. In particular, there is no evidence for embedded far-infrared sources or compact H II regions associated with the dust cores located in a dust ridge which bridges the radio arc and Sgr B1. These dust cores may be unusually cold. The two major sites of high-mass star formation in the nuclear disk, Sgr B2 and Sgr C, appear to coincide with the location of the inner Lindblad resonance. This region has been suggested as a location of enhanced star formation in circumnuclear regions of a number of barred galaxies.