  Recent observations of the deeply embedded L1551 IRS5 system permit the
detailed examination of the properties of both the stellar binary and the
binary jet. For the individual components of the stellar binary, we determine
their masses, mass accretion rates, effective temperatures and luminosities.
For the atomic wind/jet flow, we determine the mass loss rate, yielding
observationally determined values of the ratio of the mass loss to the mass
accretion rate, f. For the X-ray emitting region in the northern jet, we have
obtained the jet-velocity and derive the extinction and the densities on
different spatial scales. Examining the observational evidence within the
framework of the x-wind theory leads us to conclude that these models are
indeed potentially able to account for the observational data for this deeply
embedded source.
