Endoscales-More Signs of the Spines?
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Besides the evidence mentioned in Section 5, other data hint at well-collimated
substructure within features usually termed ``jets'':
- 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.
- 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).
- 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