Disk Masses for Embedded Class I Protostars in the Taurus Molecular
  Cloud
  Class I protostars are thought to represent an early stage in the lifetime of
protoplanetary disks, when they are still embedded in their natal envelope.
Here we measure the disk masses of 10 Class I protostars in the Taurus
Molecular Cloud to constrain the initial mass budget for forming planets in
disks. We use radiative transfer modeling to produce synthetic protostar
observations and fit the models to a multi-wavelength dataset using a Markov
Chain Monte Carlo fitting procedure. We fit these models simultaneously to our
new CARMA 1.3 mm observations that are sensitive to the wide range of spatial
scales that are expected from protostellar disks and envelopes so as to be able
to distinguish each component, as well as broadband spectral energy
distributions compiled from the literature. We find a median disk mass of 0.018
M$_{\odot}$ on average, more massive than the Taurus Class II disks, which have
median disk mass of $\sim$0.0025 M$_{\odot}$. This decrease in disk mass can be
explained if dust grains have grown by a factor of 75 in grain size, indicating
that by the Class II stage, at a few Myr, a significant amount of dust grain
processing has occurred. However, there is evidence that significant dust
processing has occurred even during the Class I stage, so it is likely that the
initial mass budget is higher than the value quoted here.
