High-resolution surveys of the Sagittarius a molecular cloud complex in ammonia, carbon monoxide, and isocyanic acid

We have observed the Sagittarius A molecular cloud complex in 10 molecular transitions. We find that excitation temperatures of CO and HNCO are in the range 10--30 K, with the CO temperatures slightly higher, while the rotation temperature T/sub rot/[NH3 (2--1)] is approx.35 K. In contrast, T/sub rot/[NH3 (6--3)] is approx.80 K. All these temperatures are relatively uniform across the complex. The masses of individual clouds are estimated by two methods; the resulting estimates are in good agreement in most cases. The three largest clouds have masses of densities approx.3--5 x 105 M/sub sun/, while four smaller features have masses of approx.105 M/sub sun/. The resulting estimated mean number densities are approx.104--105 cm-3