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arXiv · 1703.03464

Gravitational collapse of the OMC-1 region

A. Hacar·J. Alves·M. Tafalla·J. R. Goicoechea
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Abstract

We have investigated the global dynamical state of the Integral Shaped Filament in the Orion A cloud using new N$_2$H$^+$ (1-0) large-scale, IRAM30m observations. Our analysis of its internal gas dynamics reveals the presence of accelerated motions towards the Orion Nebula Cluster, showing a characteristic blue-shifted profile centred at the position of the OMC-1 South region. The properties of these observed gas motions (profile, extension, and magnitude) are consistent with the expected accelerations for the gravitational collapse of the OMC-1 region and explain both the physical and kinematic structure of this cloud.

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A. Hacar, J. Alves, M. Tafalla, J. R. Goicoechea. 2017-03-09. Gravitational collapse of the OMC-1 region. https://doi.org/10.1051/0004-6361/201730732

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