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A Single Distance Sample of Molecular Outflows from High-Mass Young Stellar Objects

Naomi A. Ridge·Toby J. T. Moore
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Abstract

We have made 12CO 2-1 and 1-0 maps of eleven molecular outflows associated with intermediate to high-mass young stellar objects (YSOs) in order to establish whether the correlations between outflow parameters and source bolometric luminosity hold in the high-mass regime. It is important to consider the effects of Malmquist-type biases when looking at high-mass YSOs, as they are generally much more distant than their low mass counterparts. We therefore chose only objects located at ~2kpc. We find that the relations show much more scatter than is seen in similar studies of low-mass YSOs. We also find that the mass-spectrum is significantly steeper in high-mass outflows, indicating a larger mass-fraction at lower velocities, a low collimation factor (~1-2) and no Hubble-like relationship.

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Naomi A. Ridge, Toby J. T. Moore. 2001-08-23. A Single Distance Sample of Molecular Outflows from High-Mass Young Stellar Objects. https://doi.org/10.1051/0004-6361%3A20011180

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