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Date and Time of the Query: 2019-05-26 T17:48:29 PDT
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Notes for object 3C 055

2 note(s) found in NED.


1. 1997ApJS..112..415M
Re:3C 055
3C 55 (z=0.7348; Fig. 4).--This object resolves into two components separated
by 0.8" and oriented in P.A. 115^deg^, roughly along the radio axis. The western
component lies within 0.5" (see Table 3) of the core positions reported in
Fernini et al. (1993).

2. 1993AJ....105.1690F
Re:3C 055
3C 55
This source is a 69" double previously imaged at radio wavelengths by
Jenkins et al. (1977), Schilizzi et al. (1982), Strom & Conway (1985),
and Leahy et al. (1989). Laing et al. (1983) gave an optical
identification with a galaxy at z = 0.27 but Spinrad (private
communication, reported in Hewitt & Burbidge 1991) has since reidentified
the source with a galaxy at z = 0.7348. The radio core peaks at
{alpha} = 01^h^54^m^19.055^s^ and {delta} = 28^deg^37'2.84", and is
slightly resolved (suggesting some jet emission is present). Leahy et al.
also report the detection of this radio core at 5, 8, and 15 GHz at a
preliminary position (Leahy 1992), 0.004^s^ earlier than ours in right
ascension and 0.07" north of ours in declination; both of these offsets
are well within the errors of the radio observations. Both radio
positions disagree by about 2" in {delta} with that quoted by Spinrad of
{alpha} = 01^h^54^m^19.03^s^ and {delta} = 28^deg^37'00.6" for the
revised optical identification, which is marked by a cross in Fig. 3.
This discrepancy in declination leaves the new optical identification in
some doubt.
Figure 3(b) shows the detailed structure of the eastern lobe. Several
resolved features (Fl through F6) occur along the lower boundary of the
lobe (Fig. 1). Features F2 (16.6 mJy peak), F6 (13.2 mJy peak), and F8
(30 mJy peak) have the highest surface brightnesses and are resolved
(Table 6). However, F8 is the brightest feature in the eastern lobe, is >
4 times brighter than the surrounding, diffuse emission, and is <1% of
the diameter of 3C 55, thus meeting our criteria for a hot spot. It is
conceivable, that features F1 through F6 might be part of a main jet in
3C 55 that is not detected within 22" (120 kpc) of the core. This would
be an exceptionally long "gap" for a jet in a radio galaxy, however, and
more sensitive observations are needed to test whether this collection of
features is indeed part of a jet, and not merely secondary structure in
the lobe. The individual features are disparate in their alignment and
polarization properties [see Fig. 3(b)], casting further doubt on their
collective status as a jet.
The western lobe, shown in detail in Fig. 3(c), has a striking "horn"-
like structure. The opening angle of the "horn" is about 30^deg^ and
appears to increase toward the core following an initially well-
collimated structure near the western extremity of the lobe. Figure 3(c)
also suggests that the western hot spot is connected to the horn
structure by a narrow bridge. This structure resembles that seen in the
numerical model of a restarting jet by Clarke & Burns (1991). Table 6
reports the hot spot sizes of each lobe, the core/lobe-feature distances,
and the lobe flux densities at 5 GHz.
At 3.6 cm, the candidate jet of 3C 55 and the radio core are also
detected [Fig. 3(d)] at a resolution of about 0.7". The peak intensity of
the core is 3.4 mJy. Figures 3(e) and 3(f) reveal the detailed structures
of the eastern and the western lobes at 3.6 cm with polarization E
vectors overlaid. Figure 3(g) shows a 20 cm contour map of the total
intensity at 4.2" resolution with polarization E vectors overlaid.


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