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Proper motions and velocity asymmetries in the RW Aur jet

L. Lopez-MArtin·S. Cabrit·C. Dougados
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Abstract

We present adaptive optics spectro-imaging observations of the RW Aur jet in optical forbidden lines, at an angular resolution of 0.4 arcsec. Comparison with HST data taken 2 years later shows that proper motions in the blueshifted and redshifted lobes are in the same ratio as their radial velocities, a direct proof that the velocity asymmetry in this jet is real and not an emissivity effect. The inferred jet inclination to the line of sight is i = 46 +/- 3 degrees. The inner knot spacing appears best explained by time variability with at least two modes: one irregular and asymmetric (possibly random) on timescales of <3-10 yr, and another more regular with ~ 20 yr period. We also report indirect evidence for correlated velocity and excitation gradients in the redshifted lobe, possibly related to the blue/red velocity and brightness asymmetry in this system.

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L. Lopez-MArtin, S. Cabrit, C. Dougados. 2003-07-07. Proper motions and velocity asymmetries in the RW Aur jet. https://doi.org/10.1051/0004-6361%3A20030758

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