A detailed study of G35.2-0.7N: Collimated outflows in a cluster of high-mass young stellar objects

Abstract

We present a series of James Clerk Maxwell Telescope, Berkeley-Illinois-Maryland Association (BIMA) and Very Large Array (VLA) observations of the massive star-forming region associated with G35.2-0.7N. These new observations shed considerable light on the nature of the outflows in this region. The combination of our CO, SiO and radio data suggests that there are perhaps as many as four outflows emanating from the core containing G35.2-0.7N. CO J = 3 → 2 maps show that the outflow has a curved appearance consistent with precession of a central driving source. However, the geometric centre of the flow is found to be not coincident with the radio jet source G35.2N but is instead closer to a peak in SiO, H13CO + and dust continuum found in the BIMA data. An elongated finger of CO emission is detected to the north of centre which points back towards the radio jet centred on G35.2N, further ruling it out as the driving source of the larger-scale CO flow. BIMA observations of the 3.5-mm continuum (which is dominated by dust), H13CN and H13CO+ emission trace a dense, elongated, rotating envelope with properties in good agreement with values derived from previous ammonia observations. The peak of the dust continuum and the H13CO+ peak a few arcsec to the south of G35.2N. SiO J = 2 → 1 data delineate a well-collimated feature parallel with the axis of the CO outflow, but offset to the north by ∼10 arcsec. H13CO+ emission is detected at the possible origin of this flow but no radio source is observed. VLA A-configuration observations at 6 and 3.5 cm resolve the radio jet into at least six discrete components, with positions consistent with previous observations. The central driving source, G35.2N, is only detected at 3.5 cm. At least two other sources are detected, one of which lies within the flattened core and may be associated with another flow inferred from recent L′-band observations. No radio source is detected at the geometric centre of the CO outflow.