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arXiv · 1910.13591

Binary outflows from young stars: interaction of co-orbital jet and wind

Abstract

Jets from young stellar objects provide insight into the workings of the beating heart at the centre of star forming cores. In some cases, multiple pulsed outflows are detected such as the atomic and molecular jets from a proposed binary system in the T\,Tauri star HH30. We investigate here the development and propagation of duelling atomic and molecular outflows stemming from the two stars in co-orbit. We perform a series of numerical experiments with the {\small ZEUS-MP} code with enhanced cooling and chemistry modules. The aim of this work is to identify signatures on scales of order 100 AU. The jet sources are off the grid domain and so it is the propagation and interaction from ~ 20AU out to 100\,AU simulated here. We find that the molecular flow from the orbiting source significantly disturbs the atomic jet, deflecting and twisting the jet and disrupting the jet knots. Regions of high ionisation are generated as the atomic jet rams through the dense molecular outflow. Synthetic images in atomic and molecular lines are presented which demonstrate identifying signatures. In particular, the structure within the atomic jet is lost and H-alpha may trace the walls of the present CO cavity or where the walls have been recently. These results provide a framework for the interpretation of upcoming high resolution observations.

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Chris J. R. Lynch, Michael D. Smith, Simon C. O. Glover. 2019-10-30. Binary outflows from young stars: interaction of co-orbital jet and wind. https://doi.org/10.1093/mnras/stz2985

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