  We have carried out mapping observations of the molecular core associated
with the young Class 0 protostar, IRAM 04191+1522, in the CH3OH (JK=2K-1K) and
C34S (J=2-1) lines using the 45 m telescope at Nobeyama Radio Observatory. As
well as an elongated envelope associated with the protostellar formation (size
\~0.07 pc x 0.04 pc, mass ~ 2.3 Mo), two compact (~ 0.03 pc) condensations were
found in the CH3OH line at the southern edge of the elongated envelope, where
the blueshifted CO outflow emerging from the protostar is located. In contrast
to the elongated envelope, those compact CH3OH condensations show much larger
line width (up to 2.0 km s-1) with centroid velocities blueshifted by ~ 0.8 km
s-1. The compact condensations have momenta (~ 0.06 Mo km s-1) comparable to
that of the blueshifted molecular outflow. These results suggest that the
compact condensations are probably formed in the course of interaction between
the outflow and the ambient gas surrounding the protostar, and that such
interaction may cause dissipation of a part of the ambient gas. No drastic,
localized enhancement of the CH3OH abundance is, however, observed toward the
compact condensations, implying that there seems to be no significant shock
heating at the compact condensations. This may be because the CO outflow
velocity (< 10 km s-1) is too low to cause effective heating to release CH3OH
on dust grains into gas phase.
