J. C. Mottram, C. M. Brunt
We present $^{12}$CO, $^{13}$CO and C$^{18}$O (J=3$-$2) observations of a new
cluster of outflows in the Vulpecula Rift with HARP-B on the JCMT. The mass
associated with the outflows, measured using the $^{12}$CO HARP-B observations
and assuming a distance to the region of 2.3 kpc, is 129 \msol{}, while the
mass associated with the dense gas from C$^{18}$O observations is 458 \msol{}
and the associated sub-millimeter core has a mass of 327 $\pm$ 112 \msol{}
independently determined from Bolocam 1.1mm data. The outflow-to-core mass
ratio is therefore $\sim$0.4, making this region one of the most efficient
observed thus far with more than an order of magnitude more mass in the outflow
than would be expected based on previous results. The kinetic energy associated
with the flows, 94$\times10^{45}$ ergs, is enough to drive the turbulence in
the local clump, and potentially unbind the local region altogether. The
detection of SiO (J=8$-$7) emission toward the outflows indicates that the flow
is still active, and not simply a fossil flow. We also model the SEDs of the
four YSOs associated with the molecular material, finding them all to be of mid
to early B spectral type. The energetic nature of the outflows and significant
reservoir of cold dust detected in the sub-mm suggest that these intermediate
mass YSOs will continue to accrete and become massive, rather than reach the
main sequence at their current mass.
View original:
http://arxiv.org/abs/1109.3598
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