2010ApJ...719.1918R

Deep Very Large Array imaging of the binary X-ray source SS 433, also classified as a microquasar, has been used to study the intrinsic brightness distribution and evolution of its radio jets. The intrinsic brightness of the jets as a function of age at emission of the jet material τ is recovered by removal of the Doppler boosting and projection effects. We find that, intrinsically, the two jets are remarkably similar when compared for equal τ, and that they are best described by Doppler boosting of the form D ^2+α, as expected for continuous jets. The intrinsic brightnesses of the jets as functions of age behave in complex ways. In the age range 60 days < τ < 150 days, the jet decays are best represented by exponential functions of τ, but linear or power-law functions are not statistically excluded. This is followed by a region out to τ =~ 250 days during which the intrinsic brightness is essentially constant. At later times, the jet decay can be fit roughly as exponential or power-law functions of τ.