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arXiv · 1710.01401

ALMA discovery of a rotating SO/SO$_2$ flow in HH212. A possible MHD disk wind?

B. Tabone·S. Cabrit·E. Bianchi·J. Ferreira·G. Pineau des Forêts·C. Codella·A. Gusdorf·F. Gueth·L. Podio·E. Chapillon
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Abstract

We wish to constrain the possible contribution of a magnetohydrodynamic disk wind (DW) to the HH212 molecular jet. We mapped the flow base with ALMA Cycle 4 at 0.13"$\sim$ 60 au resolution and compared these observations with synthetic DW predictions. We identified, in SO/SO$_2$, a rotating flow that is wider and slower than the axial SiO jet. The broad outflow cavity seen in C$^{34}$S is not carved by a fast wide-angle wind but by this slower agent. Rotation signatures may be fitted by a DW of a moderate lever arm launched out to $\sim$ 40 au with SiO tracing dust-free streamlines from 0.05-0.3 au. Such a DW could limit the core-to-star efficiency to $\leq$50%.

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B. Tabone, S. Cabrit, E. Bianchi, J. Ferreira, G. Pineau des Forêts, C. Codella, A. Gusdorf, F. Gueth, L. Podio, E. Chapillon. 2017-10-03. ALMA discovery of a rotating SO/SO$_2$ flow in HH212. A possible MHD disk wind?. https://doi.org/10.1051/0004-6361/201731691

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