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Applications of precision astrometry to studies of massive YSOs

M. J. Rioja·L. Moscadelli·R. Cesaroni
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Abstract

We present VLBI observations of the H$_2$O maser emission towards a selection of massive young stellar objects (YSOs). In one of these sources, IRAS20126+4104, the measured proper motions confirm that the water masers spots are tracing the very root (around 100 AU) of a conical bipolar outflow emerging near the position of the embedded YSO, and are an excellent tool to investigate the structure and kinematics of the outflow/jet. We also present preliminary results of a first epoch EVN observations of a selection of 5 high-mass YSO to assess the precise association of maser spots and molecular outflows in these sources.

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M. J. Rioja, L. Moscadelli, R. Cesaroni. 2004-12-17. Applications of precision astrometry to studies of massive YSOs. https://arxiv.org/abs/astro-ph/0412467

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