3 Results

   

Table 1: Radio properties of the galaxies.

name	dust	D	peak flux	RA	Dec	L	$\delta$	NVSS flux
(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)
ngc 1400	2	25.4$^{\rm P}$	2.092 $\pm$ 0.02	03 39 30.815	-18 41 17.42	1.61 $\pm$ 0.02	1.80	2.5 $\pm$ 0.5
ngc 1439	4	20.9$^{\rm T}$	<0.1
ngc 2549	0	15.7$^{\rm R}$	<0.1
ngc 2592	4	25.5$^{\rm R}$	0.41 $\pm$ 0.02	08 27 08.040	25 58 13.00	0.32 $\pm$ 0.01	0.65
ngc 2699	4	21.8$^{\rm R}$	<0.1
ngc 2768	4	16.7$^{\rm T}$	10.71 $\pm$ 0.02	09 11 37.418	60 02 14.84	3.59 $\pm$ 0.01	0.54	14.5 $\pm$ 0.6
ngc 2778	0	25.4$^{\rm T}$	<0.1
ngc 2974	3	25.9$^{\rm T}$	5.22 $\pm$ 0.02	09 42 33.310	-03 41 57.09	4.19 $\pm$ 0.02	0.93	10.4 $\pm$ 0.5
ngc 2986*	0	22.3$^{\rm T}$	8.40 $\pm$ 0.03	09 44 27.256	-21 16 11.23		160.14
ngc 3078	4	29.0$^{\rm R}$	124.95 $\pm$ 0.04	09 58 24.630	-26 55 36.09	125.73 $\pm$ 0.04	1.45	279 $\pm$ 8
ESO 437-15	3	32.3$^{\rm R}$	1.76 $\pm$ 0.04	10 36 58.100	-28 10 34.70	2.20 $\pm$ 0.05	0.80	3.2 $\pm$ 0.6
ngc 3156	2	14.0$^{\rm T}$	<0.1
ngc 3226	3	17.3$^{\rm R}$	7.29 $\pm$ 0.05	10 23 27.005	19 53 54.75	2.61 $\pm$ 0.02	0.97
ngc 3348	0	38.5$^{\rm R}$	1.66 $\pm$ 0.02	10 47 10.000	72 50 22.71	2.94 $\pm$ 0.04	1.36	7.8 $\pm$ 0.5
ngc 3377	1	9.1$^{\rm T}$	<0.1
ESO 378-20	0	35.6$^{\rm R}$	<0.1
ngc 3595	0	30.4$^{\rm R}$	0.22 $\pm$ 0.01	11 15 25.180	47 26 50.60	0.24 $\pm$ 0.01	3.87
ngc 3610*	3	26.8$^{\rm R}$	1.17 $\pm$ 0.03	11 18 20.700	58 49 38.11		230.78
ngc 4125*	4	20.1$^{\rm R}$	1.23 $\pm$ 0.02	12 08 04.180	65 09 41.32		86.29
ngc 4233	4	29.6$^{\rm R}$	2.52 $\pm$ 0.01	12 17 07.679	07 37 27.33	2.64 $\pm$ 0.01	1.02	2.9 $\pm$ 0.5
ngc 4365	0	15.7$^{\rm R}$	<0.1
ngc 4406	4	17.0$^{\rm V}$	0.59 $\pm$ 0.02	12 26 11.770	12 56 46.40	0.204 $\pm$ 0.07	1.37
ngc 4476	3	24.7$^{\rm T}$	<0.1
ngc 4494	4	17.8$^{\rm R}$	0.27 $\pm$ 0.01	12 31 24.030	25 46 30.01	0.10 $\pm$ 0.01	2.00
ngc 4552	4	17.0$^{\rm V}$	93.40 $\pm$ 0.02	12 35 39.805	12 33 22.78	32.30 $\pm$ 0.01	0.35	100 $\pm$ 3
ngc 4697	4	15.5$^{\rm T}$	<0.1
ngc 4742	3	15.9$^{\rm T}$	<0.1
ngc 5198	0	34.1$^{\rm R}$	0.83 $\pm$ 0.02	13 30 11.390	46 40 14.80	1.15 $\pm$ 0.03	1.16	3.6 $\pm$ 0.4
ngc 5322	4	23.9$^{\rm T}$	13.60 $\pm$ 0.02	13 49 15.269	60 11 25.92	9.33 $\pm$ 0.01	1.08	64 $\pm$ 2
ngc 5557	0	42.5$^{\rm R}$	<0.1
ngc 5576	0	19.1$^{\rm R}$	<0.1
ngc 5812	4	24.6$^{\rm R}$	<0.1
ngc 5813	4	24.6$^{\rm R}$	2.95 $\pm$ 0.02	15 01 11.234	01 42 07.10	2.14 $\pm$0.01	0.72	12.3 $\pm$ 0.7
ngc 5845	4	18.1$^{\rm T}$	<0.1
ngc 5982	0	39.3$^{\rm R}$	<0.1
ngc 6278	0	37.1$^{\rm R}$	1.06 $\pm$ 0.01	17 00 50.325	23 00 39.73	1.75 $\pm$ 0.02	0.62

Column 1: name of the galaxy, sources with a star are far from the nuclear region of the corresponding galaxies and were treated as non detections; Col. 2: level of dust: 0 = no dust, 1 = filamentary low, 2 = filamentary medium, 3 = filamentary high, 4 = dusty disk (Tran et al. 2001); Col. 3: distance in Mpc from (P) - Perrett et al. 1997, (T) - Tran et al. 2001, (R) - Rest et al. 2001, (V) - Virgo galaxies, assumed to be at distance of 17 Mpc; Col. 4: flux at 3.6cm in mJy, or 4$\sigma$ upper limits for nondetections; Cols. 5 and 6: radio position (h, m, s) and (deg, arcmin, arcsec) from our maps (J2000); Col. 7: luminosity in 10²⁰ WHz^-1; Col. 8: offset in arcseconds, between the 3.6 cm radio position and the position of the galaxy optical nucleus on HST images (Tran et al. 2001, Rest et al.  2001); Col. 9: peak flux from NVSS survey (Condon et al. 1998).

Twenty galaxies in our sample of 36 were detected as radio sources. Three detected sources (associated with NGC 2986, NGC 3610, NGC 4125) cannot be matched with the central regions of the galaxies and there are no visible counterparts on the available HST pictures, hence they are most likely background sources. The radio sources lay far from the nuclei (about $2\farcm 67$ for NGC 2986, $3\farcm84$ for NGC 3160, and $1\farcm44$ for NGC 4125). Although the fluxes and positions of these sources are listed in Table 1 (with asterisks) we treat them as non-detections of central AGNs in the surveyed galaxies. This leaves 17 AGN detections in 36 galaxies (47% detection rate). The smallest signal to noise ratio (SNR) is about 10$\sigma$ with a survey average rms $\sigma=2.8 \times 10^{-5}\>{\rm Jy/ beam}$. For non-detected sources we calculated the 4$\sigma$upper limits on detection, thus, the detection limit of our survey is about 0.1 mJy. Radio properties of the sample are given in Table 1. By comparison, the detection limit of the NVSS (Condon et al. 1998) used by Tran et al. (2001) to discuss radio properties of our sample is $\sim$3 mJy, a factor of 30 higher.

Most of the detections are point-like, unresolved structures. NGC 5322 is the only galaxy with noticeable jet-like structure. Typical detected sources are on the level of a few mJy; the weakest detections were $\sim$$200~\mu$ Jy. Of the 36 galaxies in the sample, 24 galaxies show disk or filamentary dust structure and 13 (54%) of them are detected as radio sources. Twelve show no dust of which four (33%) are detected.