2004AJ....127.2565D

Query : 2004AJ....127.2565D

2004AJ....127.2565D - Astron. J., 127, 2565-2578 (2004/May-0)

Optical properties of faint FIRST variable radio sources.

DE VRIES W.H., BECKER R.H., WHITE R.L. and HELFAND D.J.

Abstract (from CDS):

A sample of 123 radio sources that exhibit significant variations at 1.4 GHz on a 7 year baseline has been created using FIRST VLA B-configuration data from 1995 and 2002 on a strip at δ=0 near the south Galactic cap. This sample spans the range of radio flux densities from ∼2 to 1000 mJy. It presents both in size and radio flux density range a unique starting point for variability studies of galaxies and quasars harboring lower luminosity active galactic nuclei (AGNs). We find, by comparing our variable and nonvariable control samples with the Sloan Digital Sky Survey, the following: (1) The quasar fraction of both the variable and nonvariable samples declines as a function of declining radio flux density levels; (2) our variable sample contains a consistently higher fraction of quasars than the nonvariable control sample, irrespective of radio flux; (3) the variable sources are almost twice as likely to be retrieved from the optical SDSS data than the nonvariable ones; (4) based on relative numbers, we estimate that quasars are about 5 times more likely to harbor a variable radio source than are galaxies; and (5) there does not appear to be any significant optical color offset between the two samples, even though the suggestive trend for sources to be bluer when a variable has been detected before and may be real. This leads us to conclude that both radio variability and radio flux density levels, in combination with accurate optical information, are important discriminators in the study of (radio) variability of galaxies. The latter start to dominate the source counts below ∼20 mJy. In any case, variability appears to be an intrinsic property of radio sources and is not limited to quasars. Radio variability at low flux density levels may offer a unique tool in AGN unification studies.

Abstract Copyright: ∼

Journal keyword(s): Galaxies: Active - Galaxies: Statistics - Galaxies: Quasars: General

VizieR on-line data: <Available at CDS (J/AJ/127/2565): table2.dat>

Simbad objects: 126

goto Full paper

goto View the references in ADS

Number of rows : 126
N Identifier Otype ICRS (J2000)
RA 		ICRS (J2000)
DEC 		Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2026 		#notes
1 FBQS J0001-0020 QSO 00 01 11.1962212464 -00 20 11.564753172   19.78 19.49     ~ 41 0
2 2MASS J00025710-0024467 BLL 00 02 57.1754917488 -00 24 47.275983288   20.83 20.22 19.7   ~ 22 1
3 SDSS J000549.90+005048.1 QSO 00 05 49.905 +00 50 48.20           ~ 6 0
4 SDSS J001158.81-000207.5 QSO 00 11 58.810 -00 02 07.53           ~ 6 0
5 LBQS 0012-0024 QSO 00 15 07.0091850480 -00 08 00.972641868   18.96 18.56     ~ 50 0
6 QSO B0013-005 Bla 00 16 11.08855044 -00 15 12.4454125   20.44 19.98 19.72   ~ 171 1
7 NVSS J001800+000317 Rad 00 18 01.119 +00 03 21.83           ~ 2 1
8 NVSS J002354+001920 rG 00 23 54.58192 +00 19 19.3906           ~ 1 0
9 SDSS J002738.25+000627.2 QSO 00 27 38.252 +00 06 27.26           ~ 2 0
10 AT20G J003007-000007 BLL 00 30 07.8882351984 -00 00 07.271873172           ~ 12 2
11 SDSS J003127.91+003959.6 QSO 00 31 27.912 +00 39 59.64           ~ 6 0
12 FIRST J003536.3-000627 rG 00 35 36.29446 -00 06 27.1156           ~ 1 0
13 FIRST J003540.2-002529 rG 00 35 40.2193 -00 25 29.237           ~ 2 0
14 SDSS J003703.35+003537.5 QSO 00 37 03.35279 +00 35 37.6029   21.93 21.56     ~ 8 0
15 QSO B0041+001 Bla 00 43 32.7108513744 +00 24 59.858379792   19.52 19.26 19.3   ~ 43 1
16 QSO B0045-000 QSO 00 48 19.1211502872 +00 14 57.132827664   20.23 20.00     ~ 40 1
17 LBQS 0049+0019A QSO 00 52 05.5690063368 +00 35 38.149368180   16.54 16.22     ~ 58 1
18 FIRST J005212.4+000945 Rad 00 52 12.471 +00 09 45.29           ~ 1 0
19 FIRST J005225.6+002628 rG 00 52 25.65696 +00 26 28.0392           ~ 2 0
20 QSO B0054-0040 Bla 00 57 17.00220926 -00 24 33.1774397   19.38 19.16 19.2   ~ 91 1
21 NVSS J010525+001121 rG 01 05 25.53021 +00 11 21.5190           ~ 4 0
22 NVSS J010745+003952 Rad 01 07 45.227 +00 39 52.80           ~ 1 0
23 FIRST J010838.5+002814 Rad 01 08 38.561 +00 28 14.59           ~ 1 0
24 FIRST J011106.7+000846 QSO 01 11 06.787 +00 08 46.42           ~ 2 0
25 NVSS J011515+001247 rG 01 15 15.7840956960 +00 12 48.538049652   15.68 15.0     ~ 80 1
26 4C -00.09 QSO 01 22 13.91050430 -00 18 01.0511827           ~ 24 1
27 QSO J0125-0006 Bla 01 25 28.8438355224 -00 05 55.930595964   16.92 16.64 16.30   ~ 305 1
28 SDSS J012753.69+002516.4 QSO 01 27 53.6984800440 +00 25 16.526175600   20.72 20.61 20.7   ~ 30 1
29 SDSS J013457.43+003943.1 QSO 01 34 57.438 +00 39 43.14           ~ 6 0
30 SDSS J013815.13+001449.1 QSO 01 38 15.13112 +00 14 49.1304           ~ 9 1
31 SDSS J015329.75-002214.3 QSO 01 53 29.7572438424 -00 22 14.380032468   19.54 19.20     ~ 20 0
32 FIRST J015528.4+001204 rG 01 55 28.47192 +00 12 04.4352           ~ 2 0
33 NVSS J015949-002410 rG 01 59 50.23674 -00 24 05.9689           ~ 1 0
34 FIRST J020141.0+003825 Rad 02 01 41.043 +00 38 25.50           ~ 1 0
35 PMN J0202-0017 rG 02 02 14.291 -00 17 48.29           ~ 2 1
36 2MASS J02023433+0003015 QSO 02 02 34.3245763584 +00 03 01.799506764   18.98 18.75     ~ 31 1
37 NVSS J020929-001214 rG 02 09 28.8534388536 -00 12 24.646724568           ~ 3 0
38 FIRST J021202.1-002749 AG? 02 12 02.1149 -00 27 50.221           ~ 4 1
39 PMN J0213-0018 rG 02 13 01.15451280 -00 18 14.8246920           ~ 8 1
40 NVSS J021553+001826 rG 02 15 53.6478168792 +00 18 26.861601888           ~ 7 1
41 NVSS J021756-000937 Rad 02 17 56.011 -00 09 36.06           ~ 2 0
42 [VV2006] J021840.5-001516 QSO 02 18 40.5409644888 -00 15 16.133606568   19.50 19.26     ~ 29 0
43 FIRST J022624.6+000746 rG 02 26 24.61000 +00 07 46.2160           ~ 1 0
44 [VV2006] J023105.6+000845 QSO 02 31 05.5978276440 +00 08 43.659129804   20.00 19.74     ~ 31 1
45 ICRF J025321.0+000559 Bla 02 53 21.03544712 +00 05 59.9473920       22.4   ~ 16 1
46 FIRST J025333.6+002431 Rad 02 53 33.666 +00 24 31.75           ~ 1 0
47 NVSS J025404-002630 rG 02 54 04.53773 -00 26 28.2369           ~ 1 0
48 SDSS J025859.64+003618.2 QSO 02 58 59.64824 +00 36 18.2753           ~ 2 1
49 PB 6960 BLL 02 59 28.51615658 -00 19 59.9753897   17.74 17.58 17   ~ 146 1
50 FIRST J030137.6+001746 rG 03 01 37.61313 +00 17 45.7592           ~ 1 0
51 FIRST J030317.0-002644 Rad 03 03 17.015 -00 26 44.92           ~ 2 1
52 NVSS J030702+000653 Rad 03 07 02.068 +00 06 52.23           ~ 2 0
53 LEDA 1168970 Sy1 03 08 34.3150789440 +00 33 03.323876040   17.76 17.04     ~ 24 0
54 FIRST J030933.2-001901 Rad 03 09 33.268 -00 19 01.25           ~ 1 0
55 FIRST J031006.7+001549 rG 03 10 06.69096 +00 15 48.9312           ~ 1 0
56 FIRST J031118.5+000816 Rad 03 11 18.523 +00 08 16.57           ~ 1 0
57 Z 390-20 rG 03 12 02.4900832296 -00 04 42.500355132   14.8       ~ 39 0
58 [VV2006] J031345.1-000720 QSO 03 13 45.0403882368 -00 07 20.189120592   20.59 20.30     ~ 23 0
59 NVSS J031353-000007 Rad 03 13 53.489 -00 00 04.06           ~ 1 0
60 FIRST J031357.1+003506 Rad 03 13 57.112 +00 35 06.86           ~ 1 0
61 [VV2006] J031452.1+001345 QSO 03 14 52.0691801712 +00 13 46.362023652   20.53 19.94     ~ 28 0
62 FIRST J031609.5+000108 Rad 03 16 09.567 +00 01 08.05           ~ 1 0
63 FIRST J031634.9-002039 Rad 03 16 34.978 -00 20 39.59           ~ 1 0
64 PMN J0318-0029 rG 03 18 14.42746132 -00 29 48.9314257       22.39   ~ 22 1
65 FIRST J032007.0+000354 rG 03 20 07.01129 +00 03 53.7575           ~ 1 0
66 SDSS J212000.71-001159.7 QSO 21 20 00.7129483248 -00 11 59.683232976           ~ 5 1
67 NVSS J212059+000611 Rad 21 20 58.937 +00 06 12.59           ~ 4 1
68 NVSS J212447+000746 Rad 21 24 47.343 +00 07 47.63           ~ 1 0
69 FIRST J212955.7+000759 Rad 21 29 55.699 +00 07 59.26           ~ 2 0
70 FIRST J213206.1+003519 Rad 21 32 06.148 +00 35 20.03           ~ 1 0
71 QSO B2134+0028 Bla 21 36 38.58632232 +00 41 54.2128562   17.30 17.08 17.02   ~ 580 2
72 QSO J2137+0012 QSO 21 37 48.4434169200 +00 12 19.981418580   18.46 18.28     ~ 42 0
73 SDSS J213804.05+000714.7 QSO 21 38 04.0504388728 +00 07 14.746401194           ~ 4 0
74 FIRST J214138.5+000319 QSO 21 41 38.5405104480 +00 03 19.331461620   21.05 20.83     ~ 17 0
75 FBQS J2143+0035 QSO 21 43 24.3581663352 +00 35 02.818103496   19.58 19.37     ~ 33 0
76 FIRST J214419.8+002056 QSO 21 44 19.8698408160 +00 20 55.706914932   20.61 20.18     ~ 25 0
77 FIRST J214613.3+000930 QSO 21 46 13.3095864888 +00 09 30.768826176   20.84 20.57     ~ 35 0
78 PMN J2148-0006 Rad 21 48 07.733 -00 06 30.82           ~ 4 1
79 BWE 2151+0016 QSO 21 53 49.7333 +00 31 19.355   22.04 21.20     ~ 19 1
80 FIRST J215353.9-001339 AG? 21 53 53.8964 -00 13 39.912           ~ 2 0
81 FBQS J2153+0044 QSO 21 53 59.8169368032 +00 44 12.628463496   18.5 19.43 18.7   ~ 25 0
82 FIRST J215733.6-000340 Rad 21 57 33.676 -00 03 40.50           ~ 1 0
83 FIRST J215949.9+005147 QSO 21 59 49.9150792920 +00 51 46.673472816   20.52 20.31     ~ 23 0
84 QSO B2157-0036 QSO 21 59 54.4621954872 -00 21 50.238247320   17.67 17.22     ~ 35 0
85 FIRST J220017.3-000134 QSO 22 00 17.3764926816 -00 01 34.035610512   19.65 19.52     ~ 23 0
86 PMN J2207-0002 rG 22 07 55.2 -00 02 15           ~ 9 1
87 FIRST J220822.8+002352 rG 22 08 22.91784 +00 23 52.8288           ~ 2 0
88 SDSS J221001.81-001309.6 QSO 22 10 01.8196052016 -00 13 09.715786428   20.66 20.27     ~ 24 1
89 NVSS J221031-001355 Rad 22 10 31.464 -00 13 56.00           ~ 1 0
90 FIRST J221909.4+003113 Rad 22 19 09.399 +00 31 13.61           ~ 2 0
91 NVSS J222036+003336 rG 22 20 36.31381 +00 33 34.0438           ~ 2 0
92 FIRST J222135.0-001100 QSO 22 21 35.003 -00 11 00.16           ~ 5 0
93 SDSS J222235.84+001536.3 QSO 22 22 35.8493158944 +00 15 36.313988328   20.74 20.35     ~ 25 1
94 FIRST J222704.2+004517 rG 22 27 04.2464560104 +00 45 17.551194120           ~ 14 0
95 FIRST J222726.5+001059 rG 22 27 26.53356 +00 10 59.2496           ~ 2 0
96 BWE 2224-0009 QSO 22 27 29.0601479472 +00 05 21.966887148   19.67 19.28     ~ 38 1
97 FBQS J2227+0034 QSO 22 27 44.5842030480 +00 34 50.857844844   20.46 20.20     ~ 27 0
98 2MASS J22275812+0037055 BLL 22 27 58.1313623424 +00 37 05.426018868   18.00 17.46 18.5   ~ 35 2
99 FIRST J223047.4+002756 rG 22 30 47.45880 +00 27 56.4156           ~ 2 0
100 FIRST J224224.1+005513 Q? 22 42 24.14208 +00 55 13.5336   21.1       ~ 4 0
101 FBQS J2243-0012 QSO 22 43 31.9273453656 -00 12 32.967276228   19.37 19.21     ~ 25 0
102 NVSS J224448-000616 BLL 22 44 48.0986126784 -00 06 19.566554760   19.80 19.27 19.5   ~ 26 0
103 FIRST J224627.6-001213 rG 22 46 27.703 -00 12 13.67           ~ 3 0
104 ICRF J224730.1+000006 BLL 22 47 30.19599756 +00 00 06.4623909   20.01 19.27 18.17   ~ 93 1
105 FIRST J224922.2+001804 Rad 22 49 22.286 +00 18 04.73           ~ 1 0
106 V* AZ Psc RS* 22 58 52.9208004120 -00 18 57.378808512   8.44       K0III 57 0
107 SDSS J230157.79+000351.7 QSO 23 01 57.801 +00 03 52.17           ~ 3 0
108 FIRST J230314.8+000052 Rad 23 03 14.842 +00 00 52.24           ~ 1 0
109 FIRST J230655.1+003638 rG 23 06 55.15571 +00 36 38.0922           ~ 2 0
110 FIRST J231541.6+002936 QSO 23 15 41.6644411704 +00 29 36.635558784   21.72 21.16     ~ 18 0
111 FIRST J231558.6-001205 rG 23 15 58.646 -00 12 05.09           ~ 3 0
112 FIRST J231845.8-000754 QSO 23 18 45.8146282104 -00 07 54.857968572   20.23 20.00     ~ 34 0
113 NGC 7603 Sy1 23 18 56.6538277656 +00 14 37.977066096   14.73 14.01     ~ 438 0
114 FIRST J231910.3+001859 rG 23 19 10.33392 +00 18 59.0472           ~ 3 0
115 [VV2006] J232038.0+003138 Bla 23 20 37.9916312304 +00 31 39.713608848   20.03 19.70 18.8   ~ 44 1
116 FIRST J232323.9+003327 Rad 23 23 23.960 +00 33 27.53           ~ 1 0
117 SDSS J233448.06-001401.0 QSO 23 34 48.062 -00 14 01.06           ~ 9 0
118 FIRST J233822.3+001146 QSO 23 38 22.349 +00 11 46.52           ~ 1 0
119 NVSS J233852+004844 Rad 23 38 52.460 +00 48 43.54           ~ 1 0
120 [VV2006] J234623.7+004301 QSO 23 46 23.7205475544 +00 43 01.024855248   19.29 19.12     ~ 29 0
121 [VV2006] J234939.9-001315 QSO 23 49 39.8960301048 -00 13 15.322960236   21.18 20.70     ~ 25 0
122 FIRST J235022.4+001232 rG 23 50 22.41322 +00 12 32.5321           ~ 1 0
123 2MASS J23505070-0028488 QSO 23 50 50.7309442488 -00 28 48.540149256   20.92 20.41     ~ 21 0
124 LBQS 2351-0036 Bla 23 54 09.1759863576 -00 19 47.954748072   18.80 18.48 18.1   ~ 117 1
125 FIRST J235823.9+000213 Rad 23 58 23.907 +00 02 13.27           ~ 1 0
126 FIRST J235828.7+003933 Rad 23 58 28.727 +00 39 34.07           ~ 1 0

To bookmark this query, right click on this link: simbad:objects in 2004AJ....127.2565D and select 'bookmark this link' or equivalent in the popup menu