The Spitzer c2d Survey of Nearby Dense Cores: Jet and Molecular Outflow
  Associated with a YSO in core A of L1251
  A long infrared jet has been discovered by the Spitzer c2d legacy program in
core A of L1251. It is associated with a very embedded Class 0 object with an
accretion luminosity of about 0.9 Lsun derived by radiative transfer model
fitting to the observed SED. Comparing the observed IRAC colors along the
infrared jet with those calculated from a model of an admixture of gas with a
power-law temperature distribution indicates that the jet is possibly created
by a paraboloidal bow shock propagating into the ambient medium of n(H_2)=10^5
cm^{-3}. In addition, the variation of the power-law index along the jet
suggests that the portion of hot gas decreases with distance from the jet
engine. The molecular outflow in this region has been mapped for the first time
using CO data. From the calculated outflow momentum flux, a very strong lower
limit to the average accretion luminosity is 3.6 sin i/cos^3 i Lsun, indicative
of a decrease in the accretion rate with time.
