Abstract
The radio source 3C345 is associated with a 16th magnitude quasar with z = 0.595 (ref. 1). At radio wavelengths it has six major components. From largest to smallest these are: a low brightness halo2; a 3 kpc curved jet3; three steep-spectrum components (C1, C2, and C3) which define a curved jet4,5; and a compact component D which is self-absorbed at frequencies up to at least 10 GHz. Components C2 and C3 show proper motion relative to D at an apparent superluminal speed. We present VLBI observations at 10.7 GHz which show that a new radio component C4 has appeared and is moving along a non-radial path. This behaviour is consistent with the hypothesis that bending causes the jet curvature. We interpret our observations in light of the relativistic beam model6 as this is currently the most attractive explanation for both the superluminal effect and the weak X-ray emission4.
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Biretta, J., Cohen, M., Unwin, S. et al. Non-radial ejection in 3C345. Nature 306, 42–44 (1983). https://doi.org/10.1038/306042a0
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DOI: https://doi.org/10.1038/306042a0
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