IRAS 12326-6245: Luminous very young stellar objects with a massive molecular outflow

We present a comprehensive study of the luminous young stellar object IRAS 12326-6245 at near- and mid-infrared wavelengths as well as in the millimet re wavelength range. IRAS 12326-6245 is associated with two ultracompact H II regions. These mas sive young stellar objects are surrounded by a cluster of stars revealed by the near-infrared images. With N- and Q-band imaging, we find four very de eply embedded mid-infrared sources which form a remarkable proto-Trapezium system. Both ultracompact H II regions are associated with midinfrared sour ces. In addition, a K'-band nebulosity is present which outlines the rim of the molecular outflow. The mapping in different molecular lines as well as in the lambda1.3 mm con tinuum shows that IRAS 12326-6245 is deeply embedded in a dense molecular c loud core in agreement with the steeply rising infrared spectral energy dis tributions of the ultracompact Il II regions. In the region one of the most energetic and massive bipolar molecular outflows was detected in CO(2-1), (CO)-O-18(2-1), and SO with its origin close to IRAS 12326-6245.