An SMA Continuum Survey of Circumstellar Disks in the Serpens
  Star-Forming Region
  We present observations with the Submillimeter Array of the continuum
emission at $\lambda = 1.3$ mm from 62 young stars surrounded by a
protoplanetary disk in the Serpens star-forming region. The typical angular
resolution for the survey in terms of beam size is $3.5^{\prime
\prime}\times2.5^{\prime \prime}$ with a median rms noise level of 1.6 mJy
beam$^{-1}$. These data are used to infer the dust content in disks around
low-mass stars $(0.1$-$2.5\,M_{\odot})$ at a median stellar age of $1$-$3$ Myr.
Thirteen sources were detected in the 1.3 mm dust continuum with inferred dust
masses of ${\approx} 10$-$260\,M_{\oplus}$ and an upper limit to the median
dust mass of $5.1_{-4.3}^{+6.1}\,M_{\oplus}$, derived using survival analysis.
Comparing the protoplanetary disk population in Serpens to those of other
nearby star-forming regions, we find that the populations of dust disks in
Serpens and Taurus, which have a similar age, are statistically
indistinguishable. This is potentially surprising since Serpens has a stellar
surface density two orders of magnitude in excess of Taurus. Hence, we find no
evidence that dust disks in Serpens have been dispersed as a result of more
frequent and/or stronger tidal interactions due its elevated stellar density.
We also report that the fraction of Serpens disks with $M_{\rm{dust}} \geq
10\,M_{\oplus}$ is less than 20%, which supports the notion that the formation
of giant planets is likely inherently rare or has substantially progressed by a
few Myrs.
