2007PASJ...59L..41C

begin{HTML}The protostar B335 was observed in the 1.3mm continuum and in the H₂CO 3₁₂ ⟶ 2₁₁ line with an angular resolution of about 8''. The mass of the inner envelope, detected by the dust continuum emission, is about 0.02 M_☉. The H₂CO spectrum at the protostellar position shows a blue-skewed double-peak profile, suggesting that the kinematics of the inner envelope is dominated by infall motion. When the blueshifted and the redshifted peaks were imaged separately, however, a small east-west displacement was found between the maximum positions. This displacement suggests that some part of the H₂CO emission might come from the outflowing gas. A combined effect of the infalling envelope and the outflow on the radiative transfer is discussed. This effect can make the line profile asymmetry severer than what is expected from infall-only models.