EPoS Contribution
EPoS Contribution
A Burst of Molecular Outflows From the Serpens South Protocluster

Fumitaka Nakamura
National Astronomical Observatory of Japan, Mitaka, Japan
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.