ALMA discovery of a rotating SO/SO₂ flow in HH212

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 ~ 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 ~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 ≤50%.