3 Sources structure and polarimetry

3.1 Observational parameters

The derived parameters for the low resolution observations at 320MHz and at 5GHz (VLA C-array) are listed in Table 2. Maps at higher resolution have been obtained at 8.4 and 15 GHz with the VLA in the A configuration. Values derived from the maps are listed in Table 3. Comments on the sources structure will be given in Sect. 4.

The contents of Tables 2 and 3 are: Col. 1 -source name; Col. 2 - the observing frequency in MHz; Cols. 3 to 5 - major axis, minor axis (both in arcsec) and the PA in degrees of the restoring beam major axis; Col. 6 - the rms noise in the total intensity map far from the source of emission; Col. 7 - the rms noise $\sqrt{\sigma^{2}_Q+\sigma^{2}_U}$, where $\sigma{_Q}$ and $\sigma{_U}$ are the rms noises on the blank sky in the distributions of the Stokes parameters Q and U; Col. 8 - component label; Cols. 9 and 10- RA and Dec. of the component peak; Col. 11 - peak flux density (mJy) of the component; Col. 12 - total flux density (mJy) of the component.

In Tables 4 and 5, we give the measured position angle (PA) in degrees of the electric field vector at the peak of polarized emission ($\pm$1 rms error calculated from the distribution of PAs found in a small box around the peak of polarized emission); the Rotation Measure ( $RM=\Delta\phi(\lambda)\pm n\pi/\Delta(\lambda^2)$ in radm^-2where $\phi$($\lambda$) is the PA at wavelength $\lambda$ and n an integer; when three frequencies are available, as for some of the components in Table4, the ambiguity inplied by the integer n can be resolved); the RM, corrected for the redshift; the percentage polarization; the depolarization index, defined as the ratio of the fractional polarization at longer wavelength to the fractional polarization at shorter wavelength; from the high and low resolution observations.

In order to compare the 5GHz (C-Array) and 320MHz images of 0235-197, we have produced 5GHz maps (I, Q, U) at the resolution of the 320MHz maps. This was done by restoring the 5GHz images with the appropriate Gaussian beam during imaging. The polarization parameters derived from those images are reported in Table 5.

 

 

Table 2: Low resolution observational parameters and observed properties

Source	Obs.		Beam	PA	$\sigma_{\rm t}$	$\sigma_{\rm p}$	C	R.A. (J2000)	Dec. (J2000)	Flux	Dens.
	$\nu$	maj.	min.							peak	total
	MHz	$\hbox{$^{\prime\prime}$ }$	$\hbox{$^{\prime\prime}$ }$	$\hbox{$^\circ$ }$	mJy/b	mJy/b		h   m   s	$\hbox{$^\circ$ }$    $\hbox{$^\prime$ }$    $\hbox{$^{\prime\prime}$ }~~~~$	mJy/b	mJy
0235-197	320	7.3	4.3	-17	4.1	4.5	E	02 37 44.5	-19 32 30	3430	8530
							C	42.9	25	1068	3190
							W	41.9	28	1117	2610
	4885	4.5	2.2	-70	0.3	0.1	E	44.6	36	281.6	854.0
							C	43.0	31	35.2	145.3
							W	42.0	34	70.4	266.5
1203+043	320	5.6	5.2	-2	1.1	1.3	N	12 06 20.4	04 06 21	796	-
							S	19.6	05	579	-

Figure 2: VLA image of the East lobe of 0235-197 at 8.4 GHz. Contours are at -0.3, 0.3, 0.6, 1, 2, 4, 8, 16, 32, 64 mJybeam-1. A vector length of 1 $\hbox {$^{\prime \prime }$ }=$ 10 mJybeam-1

Figure 3: VLA image of the West lobe of 0235-197 at 8.4 GHz. Contours are at -0.3, 0.3, 0.6, 1, 2, 4, 8, 16, 32, 64 mJybeam-1. A vector length of 1 $\hbox {$^{\prime \prime }$ }=$ 10 mJybeam-1

Figure 4: VLA image of the East lobe of 0235-197 at 15 GHz. Contours are at -0.4, 0.4, 0.6, 1, 2, 4, 6, 10, 15, 20 mJybeam-1. The peak flux density is 15.7 mJybeam-1. A vector length of 1 $\hbox {$^{\prime \prime }$ }=$ 6.7 mJybeam-1

Figure 5: VLA image of 0235-197 at 320 MHz. Contours are at -5, 5, 10, 20, 50, 100, 150, 200, 300, 500, 700, 1000, 1500, 2000, 2500 mJybeam-1. The peak flux density is 3430 mJybeam-1

Figure 6: VLA image of 0235-197 at 5 GHz. Contours are at1.1 $\times$ (-1, 1, 2, 4, 8, 16, 32, 64, 128, 256 mJybeam-1. The peak flux density is 419.1 mJybeam-1. A vector length of 1 $\hbox {$^{\prime \prime }$ }=$ 5 mJybeam-1

 

 

Table 3: High resolution observational parameters and observed properties

Source	Obs.		Beam	PA	$\sigma_{\rm t}$	$\sigma_{\rm p}$	C	R.A. (B1950)	Dec. (B1950)	Flux	Dens.
	$\nu$	maj.	min.							peak	total
	MHz	$\hbox{$^{\prime\prime}$ }$	$\hbox{$^{\prime\prime}$ }$	$\hbox{$^\circ$ }$	mJy/b	mJy/b		h   m   s	$\hbox{$^\circ$ }$    $\hbox{$^\prime$ }$    $\hbox{$^{\prime\prime}$ }~~~~$	mJy/b	mJy
0235-197	4860	0.55	0.37	18	0.05	0.14	E1	02 35 26.06	-19 45 34.22	74.6	128.6
							E2	26.02	34.60	33.6	58.8
							W	23.04	30.89	4.0	14.5
	8440	0.36	0.26	16	0.07	0.03	E1	26.06	34.17	44.0	109.7
							E2	26.01	34.63	16.4	51.4
							W	23.14	30.90	1.5	7.8
	14940	0.19	0.14	24	0.15	0.10	E1a	26.07	34.13	15.7	26.0
							E1b	26.07	34.37	11.0	18.0
							E2	26.02	34.60	2.2	11.0
1203+043	4860	0.41	0.40	-41	0.06	0.07	N	12 03 46.58	04 22 58.50	1.4	49.4
							C	46.48	52.90	6.2	6.7
							J1	46.23	47.46	24.0	55.4
							J2	45.94	43.90	6.6	44.9
							S			0.8	33.3
	8440	0.30	0.29	48	0.06	0.07	N	12 03 46.71	04 23 01.65	0.78	325
							C	46.47	52.67	8.7	8.7
							J1	46.22	47.65	14.8	30.2
							J2	45.94	44.12	3.0	15.2
							S			0.5	4.0
	14940	0.18	0.16	50	0.06	0.10	C	46.47	52.66	14.5	14.9
							J1	46.22	47.63	4.3	8.2