The ALMA Early Science View of FUor/EXor objects. II. The Very Wide
  Outflow Driven by HBC 494
  We present Atacama Large Millimeter/sub-millimeter Array (ALMA) Cycle-2
observations of the HBC 494 molecular outflow and envelope. HBC 494 is an FU
Ori-like object embedded in the Orion A cloud and is associated with the
reflection nebulae Re50 and Re50N. We use $^{12}$CO, $^{13}$CO and C$^{18}$O
spectral line data to independently describe the outflow and envelope
structures associated with HBC 494. The moment-1 map of the $^{12}$CO emission
shows the widest outflow cavities in a Class I object known to date (opening
angle $\sim$ 150$^{^{\circ}}$). The morphology of the wide outflow is likely to
be due to the interaction between winds originating in the inner disc and the
surrounding envelope. The low-velocity blue- and red-shifted $^{13}$CO and
C$^{18}$O emission trace the rotation and infall motion of the circumstellar
envelope. Using molecular line data and adopting standard methods for
correcting optical depth effects, we estimate its kinematic properties,
including an outflow mass on the order of 10$^{-1}$ M$_{\odot}$. Considering
the large estimated outflow mass for HBC 494, our results support recent
theoretical work suggesting that wind-driven processes might dominate the
evolution of protoplanetary discs via energetic outflows.
