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Previous theoretical studies suggest that protostellar outflow
feedback regulates ongoing and subsequent star formation in
cluster-forming clumps by regenerating and maintaining supersonic
turbulence that impedes the rapid global gravitational collapse
of the cluster-forming clumps. However, the role of protostellar
outflow feedback in cluster formation remains to be clarified
observationally. In an effort to observationally constrain the role
of the protostellar outflow feedback in cluster formation, we
carried out mapping observations toward the nearest,cluster-forming
IRDC, Serpens South, in $^{12}$CO (3-2) using ASTE 10m telescope.
We also conducted $^{12}$CO(2-1), $^{13}$CO, C$^{18}$O (2-1),
SiO (5-4), and SO observations toward the central region using
SMA and CSO telescopes.
We discovered several powerful collimated outflows that are interacting
with ambient gas. The total outflow mass, momentum, and energy are
estimated at 0.6M$_\\odot$, 8M$_\\odot$ km/s, and 64M$_\\odot$
km$^2$/s$^2$, respectively. The energy injection rate due to the
outflows is comparable to the turbulence dissipation rate in the clump,
implying that the protostellar outflows can maintain the supersonic
turbulence in this region. The total outflow energy seems only about
10 % the clump gravitational energy. We conclude that the current
outflow activity is not enough to destroy the whole cluster-forming
clump, and therefore star formation is likely to continue for several
or many local dynamical times in this region.
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