We present Submillimeter Array observations toward the 10 ^ { 4.7 } L _ { \odot } star-forming region G240.31+0.07 , in the J = 2 –1 transition of ^ { 12 } CO and ^ { 13 } CO and at 1.3 mm continuum , as well as the ^ { 12 } CO and ^ { 13 } CO observations from the Caltech Submillimeter Observatory to recover the extended emission filtered out by the interferometer .
Maps of the ^ { 12 } CO and ^ { 13 } CO emission show a bipolar , wide-angle , quasi-parabolic molecular outflow , roughly coincident with an IR nebula revealed by the Spitzer 3.6 and 4.5 \mu m emission .
The outflow has \sim 98 M _ { \odot } molecular gas , making it one of the most massive molecular outflows known , and resulting in a very high mass-loss rate of 4.1 \times 10 ^ { -3 } M _ { \odot } yr ^ { -1 } over a dynamical timescale of 2.4 \times 10 ^ { 4 } yr .
The 1.3 mm continuum observations with a 4 ^ { \prime \prime } \times 3 ^ { \prime \prime } beam reveal a flattened dusty envelope of \sim 150 M _ { \odot } , which is further resolved with a 1.2 ^ { \prime \prime } \times 1 ^ { \prime \prime } beam into three dense cores with a total mass of \sim 40 M _ { \odot } .
The central mm core , showing evidence of active star formation , approximately coincides with the geometric center of the bipolar outflow thus most likely harbors the powering source of the outflow .
Overall our observations provide the best case to date of a well-defined wide-angle molecular outflow in a > 10 ^ { 4 } L _ { \odot } star-forming region .
The outflow is morphologically and kinematically similar to low-mass protostellar outflows but has two to three orders of magnitude greater mass , momentum , and energy , and is apparently driven by an underlying wide-angle wind , hence further supports that high-mass stars up to late-O types , even in a crowded clustering environment , can form as a scaled-up version of low-mass star formation .