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