Physics of Outflows: the Binary Protostar L1551 IRS5 and its Jets
  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. 
R. Liseau (1), C. V. M. Fridlund (2) and B. Larsson (1) ((1) Stockholm   Observatory, (2) ESA-ESTEC)