Intermittent maser flare around the high-mass young stellar object G353.273+0.641 - II. Detection of a radio and molecular jet

Abstract

We report the first detection of a radio continuum and molecular jet associated with a dominant blue-shifted maser source, G353.273+0.641. A radio jet is extended 3000 au along the north-west-south-east (NW-SE) direction. H2O masers are found to be clustered in the root of a bipolar radio jet. A molecular jet is detected by thermal SiO (ρ = 0, J = 2-1) emission. The SiO spectrum is extremely wide (-120 to +87 km s-1) and significantly blueshift dominated, similar to the maser emission. The observed geometry and remarkable spectral similarity between H2O maser and SiO strongly suggest the existence of a maser-scale (~340 au) molecular jet that is enclosed by the extended radio jet. We propose a disc-masking scenario as the origin of the strong blue-shift dominance, where an optically thick disc obscures a red-shifted lobe of a compact jet. © 2012 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.