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arXiv · 1606.08445

The Turbulent Origin of Outflow and Spin Misalignment in Multiple Star Systems

Stella S. R. Offner·Michael M. Dunham·Katherine I. Lee·Hector G. Arce·Drummond B. Fielding
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Abstract

The protostellar outflows of wide-separation forming binaries frequently appear misaligned. We use magneto-hydrodynamic simulations to investigate the alignment of protostellar spin and molecular outflows for forming binary pairs. We show that the protostellar pairs, which form from turbulent fragmentation within a single parent core, have randomly oriented angular momenta. Although the pairs migrate to closer separations, their spins remain partially misaligned. We produce $^{12}$CO(2-1) synthetic observations of the simulations and characterize the outflow orientation in the emission maps. The CO-identified outflows exhibit a similar random distribution and are also statistically consistent with the observed distribution of molecular outflows. We conclude that observed misalignment provides a clear signature of binary formation via turbulent fragmentation. The persistence of misaligned outflows and stellar spins following dynamical evolution may provide a signature of binary origins for more evolved multiple star systems.

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Stella S. R. Offner, Michael M. Dunham, Katherine I. Lee, Hector G. Arce, Drummond B. Fielding. 2016-06-27. The Turbulent Origin of Outflow and Spin Misalignment in Multiple Star Systems. https://doi.org/10.3847/2041-8205/827/1/l11

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