BLAST: The Mass Function, Lifetimes, and Properties of Intermediate Mass
  Cores from a 50 Square Degree Submillimeter Galactic Survey in Vela (l =
  ~265)
  We present first results from an unbiased 50 deg^2 submillimeter Galactic
survey at 250, 350, and 500 micron from the 2006 flight of the Balloon-borne
Large Aperture Submillimeter Telescope (BLAST). The map has resolution ranging
from 36 arcsec to 60 arcsec in the three submillimeter bands spanning the
thermal emission peak of cold starless cores. We determine the temperature,
luminosity, and mass of more than one thousand compact sources in a range of
evolutionary stages and an unbiased statistical characterization of the
population. From comparison with C^(18)O data, we find the dust opacity per gas
mass, kappa r = 0.16 cm^2 g^(-1) at 250 micron, for cold clumps. We find that
2% of the mass of the molecular gas over this diverse region is in cores colder
than 14 K, and that the mass function for these cold cores is consistent with a
power law with index alpha = -3.22 +/- 0.14 over the mass range 14 M_sun < M <
80 M_sun. Additionally, we infer a mass-dependent cold core lifetime of t_c(M)
= 4E6 (M/20 M_sun)^(-0.9) years - longer than what has been found in previous
surveys of either low or high mass cores, and significantly longer than free
fall or likely turbulent decay times. This implies some form of non-thermal
support for cold cores during this early stage of star formation.
