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arXiv · 1610.03626

Misaligned Disks in the Binary Protostar IRS 43

Christian Brinch·Jes K. Jørgensen·Michiel R. Hogerheijde·Richard P. Nelson·Oliver Gressel
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Abstract

Recent high angular resolution ($\sim$0.2") ALMA observations of the 1.1 mm continuum and of HCO+ J=3-2 and HCN J=3-2 gas towards the binary protostar IRS 43 reveal multiple Keplerian disks which are significantly misaligned ($\gt$ 60$^\circ$), both in inclination and position angle and also with respect to the binary orbital plane. Each stellar component has an associated circumstellar disk while the binary is surrounded by a circumbinary disk. Together with archival VLA measurements of the stellar positions over 25 years, and assuming a circular orbit, we use our continuum measurements to determine the binary separation, a = 74 $\pm$ 4 AU, and its inclination, i $\lt$ 30$^\circ$. The misalignment in this system suggests that turbulence has likely played a major role in the formation of IRS 43.

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Christian Brinch, Jes K. Jørgensen, Michiel R. Hogerheijde, Richard P. Nelson, Oliver Gressel. 2016-10-14. Misaligned Disks in the Binary Protostar IRS 43. https://doi.org/10.3847/2041-8205%2F830%2F1%2Fl16

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