The Detection of Outflows in the Infrared-quiet Molecular Core NGC 6334/I(North).

Abstract

We find strong evidence for outflows originating in the dense molecular core NGC 6334/I(North): a 1000 M middle dot in circle molecular core distinguished by its lack of H ii regions and mid-IR emission. New observations were obtained of the SiO &parl0;2-->1&parr0; and &parl0;5-->4&parr0; lines with the SEST 15 m telescope and of the H2 (nu=1-->0) S(1) line with the ESO 2.2 m telescope. The line profiles of the SiO transitions show broad wings extending from -50 to 40 km s-1, and spatial maps of the line-wing emission exhibit a bipolar morphology with the peaks of the red and blue wing separated by 30&arcsec;. The estimated mass-loss rate of the outflow is comparable to those for young intermediate- to high-mass stars. The near-IR images show eight knots of H2 emission. Five of the knots form a linear chain that is displaced from the axis of the SiO outflow; these knots may trace shock-excited gas along the path of a second, highly collimated outflow. We propose that NGC 6334/I(North) is a rare example of a molecular core in an early stage of cluster formation.