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arXiv · 1712.08485

On the Formation of Runaway Stars BN and x in the Orion Nebula Cluster

Juan P. Farias·Jonathan C. Tan
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Abstract

We explore scenarios for the dynamical ejection of stars BN and x from source I in the Kleinmann-Low nebula of the Orion Nebula Cluster (ONC), which is important for being the closest region of massive star formation. This ejection would cause source I to become a close binary or a merger product of two stars. We thus consider binary-binary encounters as the mechanism to produce this event. By running a large suite of $N$-body simulations, we find that it is nearly impossible to match the observations when using the commonly adopted masses for the participants, especially a source I mass of $7\:{\rm{M}}_\odot$. The only way to recreate the event is if source I is more massive, i.e., $\sim20\:{\rm{M}}_\odot$. However, even in this case, the likelihood of reproducing the observed system is low. We discuss the implications of these results for understanding this important star-forming region.

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Juan P. Farias, Jonathan C. Tan. 2017-12-22. On the Formation of Runaway Stars BN and x in the Orion Nebula Cluster. https://doi.org/10.1051/0004-6361%2F201732472

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