A High Mass Dusty Disk Candidate: The Case of IRAS 18151-1208
  Many questions remain regarding the properties of disks around massive
prototstars. Here we present the observations of a high mass protostellar
object including an elongated dust continuum structure perpendicular to the
outflow. Submillimeter Array 230 GHz line and continuum observations of the
high mass protostellar object IRAS 18151-1208 along with single dish IRAM 30m
observations afford us high spatial resolution (0.8") as well as recovery of
the extended emission that gets filtered out by the interferometer. The
observations of 12CO confirm the outflow direction to be in the
southeast-northwest direction, and the 1.3 mm continuum exhibits an elongation
in the direction perpendicular to the outflow. We model the physical parameters
of the elongated structure by simultaneously fitting the observed spectral
energy distribution (SED) and the brightness profile along the major axis using
the 3D Radiative Transfer code MC3D. Assuming a density profile similar to that
of a low mass disk, we can also reproduce the observations of this high mass
protostellar object. This is achieved by using the same density distribution
and flaring parameters as were used in the low mass case, and scaling up the
size parameters that successfully modeled the circumstellar disk of several T
Tauri stars. We also calculate that a region within the inner 30 AU of such a
high mass disk is stable under the Toomre criterion. While we do not rule out
other scenarios, we show here that the observations in the high mass regime are
consistent with a scaled up version of a low mass disk. Implications on high
mass star formation are discussed.
