SUBMILLIMETER CONTINUUM SURVEY OF THE GALACTIC-CENTER

We have conducted a survey of the 800 mum continuum emission from an a pproximately 1.5-degrees x 0.2-degrees 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 l arge-scale distribution of the submillimeter continuum emission, which traces the temperature-weighted column density of dust, correlates we ll with the distribution of the radio continuum and far-infrared emiss ion. However, in the Sgr A complex and the vicinity of the radio arc t he correlation between the distribution of GMC cores traced by the dus t emission and those of compact far-infrared sources and compact H II regions is poor. This may indicate that many of the dust cores detecte d in our survey are heated by the diffuse external radiation field rat her 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 an d 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, app ear to coincide with the location of the inner Lindblad resonance. Thi s region has been suggested as a location of enhanced star formation i n circumnuclear regions of a number of barred galaxies.