Vertical Structure of the Transition Zone from Infalling Rotating
  Envelope to Disk in the Class 0 Protostar, IRAS04368+2557
  We have resolved for the first time the radial and vertical structure of the
almost edge-on envelope/disk system of the low-mass Class 0 protostar L1527.
For that, we have used ALMA observations with a spatial resolution of
0.25$^{\prime\prime}$$\times$0.13$^{\prime\prime}$ and
0.37$^{\prime\prime}$$\times$0.23$^{\prime\prime}$ at 0.8 mm and 1.2 mm,
respectively. The L1527 dust continuum emission has a deconvolved size of 78 au
$\times$ 21 au, and shows a flared disk-like structure. A thin
infalling-rotating envelope is seen in the CCH emission outward of about 150
au, and its thickness is increased by a factor of 2 inward of it. This radius
lies between the centrifugal radius (200 au) and the centrifugal barrier of the
infalling-rotating envelope (100 au). The gas stagnates in front of the
centrifugal barrier and moves toward vertical directions. SO emission is
concentrated around and inside the centrifugal barrier. The rotation speed of
the SO emitting gas is found to be decelerated around the centrifugal barrier.
A part of the angular momentum could be extracted by the gas which moves away
from the mid-plane around the centrifugal barrier. If this is the case, the
centrifugal barrier would be related to the launching mechanism of low velocity
outflows, such as disk winds.
