Endoscales-More Signs of the Spines?

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8.2 Endoscales-More Signs of the Spines? 

Besides the evidence mentioned in Section 5, other data hint at well-collimated substructure within features usually termed ``jets'':

  1. WFPC2 observations of the jet in 3C273  at V band (Bahcall et al. 1995) show that the optical emission is much narrower than the 18cm radio jet. This implies that the primary energy flow  is in a narrow ``channel"  within a more diffuse, but strongly one-sided and elongated, radio feature.

  2. The outer jet in M87  has a ``dark filament''  along its axis at both radio and optical wavelengths. This feature, which connects to an emission ``loop'' on the otherwise-sharp core-ward side of Knot  A (Biretta, these Proceedings, Fig. 4), is < 0.2 of the width of the rest of the jet (Owen, Hardee, & Cornwell 1989, Fig. 3).

  3. Both jets in the FR II radio galaxy 3C219  contain similar ultra-compact knots  at their tips, aligned across the radio nucleus to better than 0.2° (Perley, Bridle, & Clarke 1994). The compactness and near-perfect alignment of these knots argue that they mark the ends of a well-collimated flow  within the broader ``jets"-in this case a ``restarting''  jet/counterjet  pair.

Alan Bridle
Wed Apr 10 10:19:46 EDT 1996