Figures 15 to 26 show the final images obtained for the galaxies observed with the VLA. The parameters derived from these images are listed in Table 5. This table presents the radio fluxes and the fractional polarisation at 6 cm for the whole sources and their sub-regions indicated in Col. 2. In the following section we describe in more details the results for the single objects.

0039 ${\bf -}$ 44: this is a relatively small radio source with the emission dominated by the two lobes. No core or jets have been detected. Both lobes are polarised with the eastern one showing an higher fractional polarisation compared to the western side. The eastern lobe is slightly depolarised while the western side is consistent with no depolarization.

In the optical, this galaxy has a high ionization emission line spectrum with a strong blue, polarized continuum. No extended emission lines have been observed in this object.

0043 ${\bf -}$ 42: this is a very extended source with a typical FRII morphology. It was previously mapped by Duncan & Sproats (1992) and, at lower resolution (843 MHz with the Molonglo Synthesis Telescope, MOST), by Jones & McAdam (1992).

Unfortunately, at 3-cm most of the extended emission is resolved out at the resolution of our data. Thus, only the hot-spots could be imaged at this frequency and they are shown in the inserts of Fig. 3. At 6 cm no radio core has been detected. The polarisation is very uniform in the

$\begin{figure}\begin{tabular}{cc} {\psfig{figure=ds1732f10a.eps,angle=0,width=5cm}\psfig{figure=ds1732f10b.eps,angle=-90,width=5cm} } \end{tabular}\end{figure}$

Figure 10: (Left) ATCA image of 1938-15 at 3-cm (full resolution) with superimposed vectors indicating the projected electric field direction. The vectors are proportional in length to the fractional polarisation (1 arcsec = 0.07 ratio). The contour levels are: $3.0 \times -1$ , 1, 2, 4, 8, 16, 32, 64, 128 mJy beam^-1. The peak flux is 658.5 mJy beam^-1; (Right) ATCA image of 1938-15 at 6-cm with superimposed vectors indicating the projected electric field direction. The vectors are proportional in length to the fractional polarisation. The contour levels are: $3.5 \times -1$ , 1, 2, 4, 8, 16, 32, 64, 128, 256 mJy beam^-1. The peak flux is 1.240 Jy beam^-1. The cross indicates the position (from Prestage & Peacock 1983) of the optical galaxy

In the optical it shows only weak, low-ionization emission lines and its continuum appears to be typical of early-type galaxies. Thus, this is an example of FRII (and powerful) radio galaxies with significantly weaker emission lines that expected from the radio power-emission line luminosity correlation.

0409 ${\bf -}$ 75: this FRII is the highest red-shift object in the sample and one of the most powerful source in the southern hemisphere (Alvarez et al. 1993). It was previously mapped by Duncan & Sproats (1992).

It is quite a small radio source with the radio emission dominated by two bright lobes. Both lobes have an high depolarization, slightly higher in the eastern lobe. Also the rotation measure is large especially in the eastern lobe.

Interestingly, the ionization state is low for such a powerful radio galaxy: [O III] $\lambda$ 5007 is barely detected while [O II] $\lambda$ 3727 is strong. However the continuum is bluer than an elliptical galaxy at the same red-shift (Dickson 1997). According to Tadhunter et al. (1993) the [O II] $\lambda$ 3727 line is extended but this does not seem to be the case in [O III] $\lambda$ 5007.

0625 ${\bf -}$ 53: This is a FRI galaxy associated with a dumbbell galaxy (Lilly & Prestage 1987; Gregorini et al. 1994) that is also the brightest member of the cluster Abell 3391. At the resolution of our observations, it shows a wide-angle tail (WAT) structure with two tails sharply bending at about 20 arcsec north and 40 arcsec south of the nucleus. This morphology is also confirmed by the 13-cm ATCA image presented by Otani et al. (1998). From an X-ray/radio comparison, these authors found evidence for a possibly strong interaction between the radio jets and the surrounding material. The jets are deflected possibly as the result of pressure gradients or winds in the intracluster medium and they seem to "escape'' into regions of lower X-ray brightness. This galaxy has also been observed at lower resolution by Gregorini et al. (1994). In their image, the northern tail is even more prominent and a low-brightness diffuse region is also observed as a western extension (for $\sim 45$ arcsec) to the southern lobe.

The two lobes show a similar fractional polarisation at both 6 and 3 cm and they both show no significant depolarisation. The RM is quite uniform in the southern lobe but a large range of RM values is observed in the northern lobe (see Fig. 8) with the central region around $RM \sim 350$ rad m^-2, while the northern tail is showing values of $\sim -430$ rad m^-2. There is the possibility that the values are continuous at the step and the reason for the "apparent'' jump is the $n\pi$ ambiguity in the position angle: only a study of the polarisation at other frequencies will be able to confirm this jump in RM. However, it may be worth noticing that, by looking at Fig. 7 in Otani et al. (1998) (i.e. the radio/X-ray overlay), the jump in RM occurs in the region where the radio emission seems to "escape'' the brighter X-ray emission.

1938 ${\bf -}$ 15: this is another small source dominated by the radio emission from two lobes. No core or jets have been detected. It shows quite a strong asymmetry in the depolarization: the eastern lobe has the lower fractional polarisation and the stronger depolarization.

This galaxy has a high ionization emission line spectrum. From the new optical spectra (Dickson 1997) this galaxy is now classified as a Broad Line Radio Galaxy (BLRG) because it shows a prominent broad component in the MgII $\lambda$ 2800 Å and H $\beta$ . As with many other BLRG, it is detected in X-ray by ROSAT (Siebert et al. 1996).

1954 ${\bf -}$ 55: this is an FRI source comprising two jet-like structures. When observed at low frequency and low resolution (Jones & Mc Adams 1992), this object is embedded in an elongated and bent low-brightness halo extended more than 5 arcmin. The integrated spectral index we find is much steeper than from the single-dish observations (see Table 1) and this is probably due to resolved emission in the 3 cm image.

Neither jet shows evidence for significant depolarization. The rotation measure is quite uniform in the southern lobe ( $\sim 126$ rad m^-2). In the northern lobe, most of the lobe shows a value of around 18 rad m^-2except in a region (south-west) where the values are around $\sim -83$ rad m^-2.

2058 ${\bf -}$ 28: the morphology of this FRI source is better defined than in the previously available radio image. A strong jet is also now observed. The difference with the previous radio image is likely due to the short integration of the previous observations. Unfortunately, this galaxy could not be imaged properly at 3-cm and therefore we do not show the 3 cm data here. A low resolution radio image was obtained by Christiansen et al. (1977) and shows that the source is embedded in a low brightness halo, extended more than 8 arcmin, which is not visible in our image.

Two diffuse lobes without hot-spots are observed. The polarisation in these lobes has a ring-like shape and the position angle of the electric field is radial in both the lobes.

2058-28 has a core flux density higher than in the previous VLA 6 cm data. The detected difference is likely to be due to the old value of the radio core being unreliable, for the reasons mentioned above, more than variability in the core flux. Furthermore, the new core flux density is consistent with the PTI data derived at 13 cm (Morganti et al. 1997a).

In the optical it shows only weak, low-ionization emission lines and its continuum appears to be typical of early-type galaxies.

Table 4:
Object $S_{6\, {\rm cm}}$ $S_{3\, {\rm cm}}$ $m_{6\, {\rm cm}}$ $m_{3\, {\rm cm}}$ DP $^{6\, {\rm cm}}_{3\, {\rm cm}}$ $\alpha^{6\, {\rm cm}}_{3\, {\rm cm}}$ RM

Jy Jy % % rad m^-2

0039-44 Total 1.169 0.606 7.5 6.7 ... 1.20 ...

E lobe 0.678 0.344 8.0 10.2 0.79 1.24 -27

W lobe 0.486 0.261 3.7 2.7 1.35 1.14 -32

0043-42^* Total 2.776 ... 30.3 ... ... ... ...

HS North 1.182 ... 20.1 ... ... ... ...

Ext. North 0.507 ... 37.1 ... ... ... ...

HS South 0.397 ... 20.0 ... ... ... ...

Ext. South 0.550 ... 28.9 ... ... ... ...

0409-75 Total 4.508 2.315 2.5 6.6 ... 1.22 ...

E lobe 2.671 1.459 1.1 3.4 0.30 1.10 +522

W lobe 1.843 0.895 4.5 9.3 0.46 1.32 +235

0625-53 Totale 1.543 0.787 15.7 15.1 0.96 1.23 +150

Core 0.025 0.019 ... ... ... 0.47 ...

N Lobe 0.747 0.383 12.1 14.8 0.91 1.22 +43^a

S Lobe 0.691 0.351 12.6 12.3 1.02 1.24 +293

1938-15 Total 2.377 1.263 6.3 8.8 ... 1.16 ...

E lobe 1.370 0.721 2.1 3.8 0.53 1.17 -105

W lobe 1.032 0.549 11.6 13.7 0.98 1.15 -79

1954-55 Total 1.630 0.559 32.7 34.0 ... 1.95 +33

Core 0.055 0.052 ... ... ... 0.10 ...

N lobe 1.340 0.351 39.1 39.8 0.98 2.45 0^a

S lobe 0.608 0.165 26.5 23.2 1.06 2.38 126

2058-28^* Total 1.216 ... 28.0 ... ... ... ...

Core 0.123 ... ... ... ... ... ...

S lobe 0.591 ... 25.3 ... ... ... ...

S jet 0.069 ... 13.4 ... ... ... ...

N lobe 0.440 ... 33.4 ... ... ... ...

**Table 4:**
Object		$S_{6\, {\rm cm}}$	$S_{3\, {\rm cm}}$	$m_{6\, {\rm cm}}$	$m_{3\, {\rm cm}}$	DP $^{6\, {\rm cm}}_{3\, {\rm cm}}$	$\alpha^{6\, {\rm cm}}_{3\, {\rm cm}}$	RM
		Jy	Jy	%	%			rad m^-2
0039-44	Total	1.169	0.606	7.5	6.7	...	1.20	...
	E lobe	0.678	0.344	8.0	10.2	0.79	1.24	-27
	W lobe	0.486	0.261	3.7	2.7	1.35	1.14	-32

0043-42^*	Total	2.776	...	30.3	...	...	...	...
	HS North	1.182	...	20.1	...	...	...	...
	Ext. North	0.507	...	37.1	...	...	...	...
	HS South	0.397	...	20.0	...	...	...	...
	Ext. South	0.550	...	28.9	...	...	...	...

0409-75	Total	4.508	2.315	2.5	6.6	...	1.22	...
	E lobe	2.671	1.459	1.1	3.4	0.30	1.10	+522
	W lobe	1.843	0.895	4.5	9.3	0.46	1.32	+235

0625-53	Totale	1.543	0.787	15.7	15.1	0.96	1.23	+150
	Core	0.025	0.019	...	...	...	0.47	...
	N Lobe	0.747	0.383	12.1	14.8	0.91	1.22	+43^a
	S Lobe	0.691	0.351	12.6	12.3	1.02	1.24	+293

1938-15	Total	2.377	1.263	6.3	8.8	...	1.16	...
	E lobe	1.370	0.721	2.1	3.8	0.53	1.17	-105
	W lobe	1.032	0.549	11.6	13.7	0.98	1.15	-79

1954-55	Total	1.630	0.559	32.7	34.0	...	1.95	+33
	Core	0.055	0.052	...	...	...	0.10	...
	N lobe	1.340	0.351	39.1	39.8	0.98	2.45	0^a
	S lobe	0.608	0.165	26.5	23.2	1.06	2.38	126

2058-28^*	Total	1.216	...	28.0	...	...	...	...
	Core	0.123	...	...	...	...	...	...
	S lobe	0.591	...	25.3	...	...	...	...
	S jet	0.069	...	13.4	...	...	...	...
	N lobe	0.440	...	33.4	...	...	...	...

^* Values derived from the lower resolution map (3 km maximum baseline).
^a See notes to the sources (Sect. 3.1).

$\begin{figure}{\psfig{figure=ds1732f11.eps,angle=-90,width=8.8cm} } \end{figure}$

Figure 11: Image of 1954-55 at 3-cm (full resolution) with superimposed vectors indicating the projected electric field direction. The vectors are proportional in length to the fractional polarisation (1 arcsec = 0.54 ratio). The contour levels are: $1.3 \times -1$ , 1, 2, 4, 8, 16, 32 mJy beam^-1. The peak flux is 54.5 mJy beam^-1

$\begin{figure}{\psfig{figure=ds1732f12.eps,angle=-90,width=8.8cm} } \end{figure}$

Figure 12: Image of 1954-55 at 6-cm with superimposed vectors indicating the projected electric field direction. The vectors are proportional in length to the fractional polarisation (1 arcsec = 0.029 ratio). The contour levels are: $1.6 \times -1$ , 1, 2, 4, 8, 16, 32 mJy beam^-1. The peak flux is 94.0 mJy beam^-1

$\begin{figure}{\psfig{figure=ds1732f13.eps,angle=-90,width=8.8cm} } \end{figure}$

Figure 13: Image of 2058-28 at 6-cm (low resolution) with superimposed vectors indicating the projected electric field direction. The vectors are proportional in length to the fractional polarisation (1 arcsec = 0.04 ratio). The contour levels are: $1.5 \times -1$ , 1, 2, 3, 4, 6, 8, 16, 32, 64 mJy beam^-1. The peak flux is 112.0 mJy beam^-1

$\begin{figure}{\psfig{figure=ds1732f14.eps,angle=-90,width=8.8cm} } \end{figure}$

Figure 14: Zoom-in of the jet in 2058-28 at 6-cm (full resolution) with superimposed vectors indicating the projected electric field direction. The vectors are proportional in length to the fractional polarisation (1 arcsec = 0.13 ratio). The contour levels are: $1.0 \times -1$ , 1, 2, 3, 4, 6, 8, 16, 32, 64 mJy beam^-1. The peak flux is 100.6 mJy beam^-1

3.2 Radio galaxies observed with VLA

0034 ${\bf -}$ 01 (3C 15): this source is now resolved into a prominent one-sided jet, while only some structure is detected in the two lobes (due to the relatively high resolution). The southern lobe is the brighter one but only shows a "warmer'' spot (as perhaps expected looking at the low resolution image in Morganti et al. 1993). This galaxy has been observed at 3.6 cm by Leahy et al. (1997) who define its structure as intermediate between FR classes I and II of FR, although its radio luminosity is typical of class II galaxies (indeed it was classified as FRII in Morganti et al. 1993). Knots are detected along the jet as in the 3.6 cm images.

The core flux density measured in the new image is much lower than from the 6 cm VLA data: this is probably due to the fact that low resolution of the previous observations (about 3 arcsec) included the base of the strong jet in what was defined as the core.

The electric field in the jet is perpendicular to the jet axis in the first blob (closer to the nucleus) and then become parallel to the jet, although a different position angle seems to be characteristics of the regions at the edge. This is likely due to effect of shear layer as often found in jets in FRI and described in detailed by Laing et al. (1996).

In the optical only a weak [O III] $\lambda$ 5007 emission has been detected from this source (Tadhunter et al. 1993), and the continuum is typical of early-type galaxies.

0035 ${\bf -}$ 02 (3C 17): this radio galaxy presented a very peculiar radio morphology in our previous low resolution radio image (Morganti et al. 1993). The new high resolution image clarifys the real structure of this source. On the south-east side of the nucleus a very bent jet is observed. The first part of the jet is dominated by a bright blob. On the western side a lobe structure is observed with a ring-like shape, i.e. because of the minimum in intensity in the centre. Also this could be a very bent jet seen in a particular position angle. A VLBA map (Venturi et al. 1996) shows as on the milliarcsec scale a one-sided jet is observed in the eastern side and in the same position angle as the bright blob observed in our VLA map.

In this galaxy, the H $\alpha$ emission line has a strong broad component (Dickson 1997) and the [O II] $\lambda$ 3727 and [O III] $\lambda$ 5007 emission lines are extended. There is also evidence for significant optical polarization in the nucleus of the galaxy (Tadhunter et al. 1997). This object has been detected in X-rays (Siebert et al. 1996), as have most of the BLRG in our sample.

Given the optical polarization properties (Tadhunter et al. 1997) this object may be a BL Lac-type in which the jet is pointing close to the line of sight (thus accentuating any wiggles in the jet). It also looks very similar to the southern BLRG/quasar PKS 2300-18 which has been interpreted in terms of precession.

0117 ${\bf -}$ 15 (3C 38): is a double lobed radio galaxy with a typical FRII structure. No core has been detected. Both lobes have clear hot spots and the southern lobe shows a clear bend in a direction almost perpendicular to the line connecting the two lobes. Similar structure detected, e.g., in 3C 326 (Ekers et al. 1978) has been explained as result of a precessing beam. An alternative explanation has been suggested from a systematic study of bridges in double radio sources by Leahy & Williams (1984). The sharp distortion often observed in these sources can be expected as consequence of the interaction between the strong back-flow and the galactic atmosphere if the jet is much lighter than the confining medium.

In the optical, this galaxy has a high ionization spectrum with both the continuum and the line emission extended in the north-east direction. The continuum shows a strong UV/blue excess (Dickson 1997) and substantial optical polarisation (Tadhunter et al. 1997). The radio lobe on the same side as the extended emission lines is closer to the nucleus and has the lower fractional polarisation. This may indicate a higher depolarization but confirmation will require observations at different frequencies.

0442 ${\bf -}$ 28: the new radio observations for this FRII radio galaxy shows a complex morphology for its radio lobes. A core has been detected but no radio jets.

This object has strong, narrow emission lines (Tadhunter et al. 1993). It is also detected in X-rays (Siebert et al. 1996), where it appears to be extended, even though this source is not known to be associated with a cluster.

0453 ${\bf -}$ 20: from the new radio image this source appears as double lobed with a clear jet in the north-west direction ending with an hot spot. In the southern part no jet has been detected and a "warm-spot'' is visible at the edge of the lobe. The electric field is parallel to the direction of the jet and becomes radial at the edge of the lobe.

From Tadhunter et al. (1993) no optical lines are detected in this galaxy and the continuum appears typical of early-type galaxies.

1602+01 (3C 327.1): this source is dominated by a one sided knotty jet on the south-east side. This galaxy was also observed by Baum et al. (1988) with the B array at 6 cm, and by Hes (1995) at 8.4 GHz.

In the radio, 1602+01 shows clear morphological similarities with 0035-02. Similarities are also present in the optical spectrum of these objects. In fact, in the optical 1602+01 has a high ionization emission line spectrum showing (as 0035-02) a broad component of the H $\beta$ emission (Dickson 1997). The [O II] $\lambda$ 3727 and [O III] $\lambda$ 5007 may be slightly extended. As with most of the BLRG, this galaxy has been detected in X-ray emission.

1938 ${\bf -}$ 15: this object has been also observed with the ATCA and described above. From the higher resolution of the VLA map (Fig. 9) it is possible to see that the western lobe is actually extended while the eastern one is only slightly resolved. Also at the higher resolution the east lobe shows a low polarisation (as in the lower resolution ATCA image). The west lobe (now better resolved) shows a higher fractional polarisation in the VLA image ( $\sim 29$ %), indicating possible depolarization due to the beam at the resolution of ATCA.

2314+03 (3C 459): this is another small source of this sample also studied before by Ulvestad (1985). It is dominated by a strong core and two lobes. The eastern lobe is quite compact and much closer to the nucleus compared to the western one. A strong asymmetry in the polarisation can be seen between the two lobes with the eastern one much less polarised (only 2%) than the western one consistent with what was found by Ulvestad (1985). Also in this object, as in 0034-01, the new core flux density is lower than in the previous VLA data (Morganti et al. 1993). Again, the difference is likely due to the difference in resolution. In the optical this galaxy has a moderate ionization emission line spectrum and the continuum is dominated by young stars.

Table 5:
Object S $_{6\, {\rm cm}}$ $m_{6\, {\rm cm}}$

Jy %

0034-01 core 0.032 ...

jet 0.292 25.0

N lobe 0.049 ...

S lobe 0.109 53.2

0035-02 Total 1.279 33.4

core 0.530 ...

E jet 0.475 30.0

W lobe 0.275 40.3

0117-15 Total 1.336 25.2

N-E lobe 0.985 15.4

S-W lobe 0.347 35.2

0442-28 core 0.039 ...

N lobe 0.573 25.6

S lobe 0.386 37.8

0453-20 Total 0.952 47.4

core 0.034 ...

N lobe 0.546 47.1

S lobe 0.323 48.4

1602+01 Total 0.945 ...

core 0.080 ...

E lobe 0.423 21.6

W lobe 0.441 16.7

1938-15 Total 2.947 11.4

E lobe 1.729 2.8

W hot-spot 1.094 9.2

W lobe 1.269 28.5

2314+03 Total 1.294 14.4

core 0.425 2.0

E lobe 0.608 2.0

W lobe 0.260 19.2

3 Results

3.1 Radio galaxies observed with ATCA

3.2 Radio galaxies observed with VLA

Object		S $_{6\, {\rm cm}}$	$m_{6\, {\rm cm}}$
		Jy	%
0034-01	core	0.032	...
	jet	0.292	25.0
	N lobe	0.049	...
	S lobe	0.109	53.2

0035-02	Total	1.279	33.4
	core	0.530	...
	E jet	0.475	30.0
	W lobe	0.275	40.3

0117-15	Total	1.336	25.2
	N-E lobe	0.985	15.4
	S-W lobe	0.347	35.2

0442-28	core	0.039	...
	N lobe	0.573	25.6
	S lobe	0.386	37.8

0453-20	Total	0.952	47.4
	core	0.034	...
	N lobe	0.546	47.1
	S lobe	0.323	48.4

1602+01	Total	0.945	...
	core	0.080	...
	E lobe	0.423	21.6
	W lobe	0.441	16.7

1938-15	Total	2.947	11.4
	E lobe	1.729	2.8
	W hot-spot	1.094	9.2
	W lobe	1.269	28.5

2314+03	Total	1.294	14.4
	core	0.425	2.0
	E lobe	0.608	2.0
	W lobe	0.260	19.2