J/AJ/130/2473 Fine-scale structure in 250 sources at 15GHz (Kovalev+, 2005)
Sub-milliarcsecond imaging of quasars and active galactic nuclei.
IV. Fine-scale structure.
Kovalev Y.Y., Kellermann K.I., Lister M.L., Homan D.C., Vermeulen R.C.,
Cohen M.H., Ros E., Kadler M., Lobanov A.P., Zensus J.A., Kardashev N.S.,
Gurvits L.I., Aller M.F., Aller H.D.
<Astron. J., 130, 2473-2505 (2005)>
=2005AJ....130.2473K 2005AJ....130.2473K
ADC_Keywords: BL Lac objects ; Active gal. nuclei ; Radio continuum ; QSOs ;
Galaxies, radio
Keywords: BL Lacertae objects: general - galaxies: active - galaxies: jets -
quasars: general - radio continuum: galaxies - surveys
Abstract:
We have examined the compact structure in 250 flat-spectrum
extragalactic radio sources using interferometric fringe visibilities
obtained with the Very Long Baseline Array (VLBA) at 15GHz. With
projected baselines out to 440Mλ, we are able to investigate
source structure on typical angular scales as small as 0.05mas.
Description:
Our analysis is based on data obtained during the period 1994-2003
as part of the VLBA 15 GHz monitoring survey of extragalactic
sources (Kellerman et al. 1998AJ....115.1295K 1998AJ....115.1295K, Zensus et al.
2002AJ....124..662Z 2002AJ....124..662Z, Kellerman et al. Cat. J/ApJ/609/539, Lister
& Homan Cat. J/AJ/130/1389, E. Ros et al. 2006, in prep.). We have
also used additional observations made in 1998 and 1999 by L.I.
Gurvits et al. (2006, in prep.) as part of a separate program to
compare 15GHz source structure measured with the VLBA to 5GHz
structure measured in the framework of the VSOP survey program. Our
data set consists of 1204 VLBA observations of 250 different compact
extragalactic radio sources. The initial calibration of the data was
carried out with the NRAO AIPS package and was followed by imaging
with the DIFMAP program, mostly with the use of an automatic script.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 97 250 General source properties
table2.dat 85 1204 Source parameters for all epochs of observations
at 15GHz
--------------------------------------------------------------------------------
See also:
J/ApJ/609/539 : Kinematics of parsec-scale radio jets (Kellermann+, 2004)
J/AJ/130/1389 : Linear polarization images at 15GHz of AGN jets
(Lister+, 2005)
J/ApJ/616/110 : VSOP 5GHz AGN Survey. IV (Horiuchi+, 2004)
J/ApJ/609/564 : Blazar counterparts for 3EG sources (Sowards-Emmerd+, 2004)
J/ApJ/590/109 : Gamma-ray blazar in northern sky (Sowards-Emmerd+, 2003)
J/ApJS/135/155 : Radio identification of 3EG EGRET sources (Mattox+, 2001)
J/A+AS/105/211 : Optical identification status of 1Jy catalogue
(Stickel+ 1994)
J/A+A/386/97 : The Parkes quarter-Jansky flat-spectrum sample
(Jackson+, 2002)
J/ApJS/150/181 : Redshifts of 110 radio-loud AGNs (Eracleous+, 2004)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- IAU The IAU (B1950.0) name
10- 18 A9 --- Alias Object alias
20- 21 I2 h RAh Hour of Right Ascension (J2000)
23- 24 I2 min RAm Minute of Right Ascension (J2000)
26- 32 F7.4 s RAs Second of Right Ascension (J2000)
34 A1 --- DE- Sign of the Declination (J2000)
35- 36 I2 deg DEd Degree of Declination (J2000)
38- 39 I2 arcmin DEm Arcminute of Declination (J2000)
41- 47 F7.4 arcsec DEs Arcsecond of Declination (J2000)
49 A1 --- cl [QBGU] Optical classification (1)
51 A1 --- f_cl Discordant classifications (2)
53 A1 --- l_z [>] Limit flag on z
55- 59 F5.3 --- z ? Redshift (3)
61- 66 A6 --- Rsp Radio spectrum: flat, peaked or steep (4)
68- 69 A2 --- EGRET [YNP] EGRET identification (5)
71 A1 --- MOJAVE [YN] Included in the program (Monitoring of
Jets in AGN with VLBA Experiments)
73- 77 A5 --- VSOP VSOP 5GHz AGN member (6)
79- 97 A19 --- IDV Fast variations references (7)
--------------------------------------------------------------------------------
Note (1): According to the Veron-Cetty & Veron (2003, Cat. VII/248) catalog
except for 0108+388, 0742+103, and 2128+048. There classification
is from Carilli et al. (1998ApJ...494..175C 1998ApJ...494..175C), Best et al.
(2003MNRAS.346.1021B 2003MNRAS.346.1021B), and Biretta et al (1985AJ.....90.2508B 1985AJ.....90.2508B),
respectively. The optical classification is defined as follows:
Q = quasar;
B = BL Lac object;
G = active galaxy;
U = unidentified.
Note (2): Flag on classification, defined as follows:
a = Source classified as quasar in the Veron-Cetty & Veron catalog
(2003, Cat. VII/248).
b = Source classified as a probable or possible BL Lac object in the
Veron-Cetty & Veron catalog (2003, Cat. VII/248).
c = Source classified as galaxy in the Veron-Cetty & Veron catalog
(2003, Cat. VII/248).
Note (3): From Veron-Cetty & Veron (2003, Cat. VII/248). The redshift of
0108+388 is from Carilli et al (1998ApJ, 494, 175), that of 0138-097
is from Stocke & Rector (1997ApJ...489L..17S 1997ApJ...489L..17S), that of 0333+321 is
from Small et al. (1997AJ....114.2254S 1997AJ....114.2254S), that of 0415+379 is from
Eracleous & Halpern (2004, Cat. J/ApJS/150/181), that of 0742+103 is
from Best et al. (2003MNRAS.346.1021B 2003MNRAS.346.1021B), that of 0808+019 is from
Jackson et al. (2002, Cat. J/A+A/386/97) as a tentative value, that
of 1519-273 is from Heidt et al. (2004A&A...418..813H 2004A&A...418..813H), and that of
2128+048 is from Stickel et al. (1994, Cat. J/A+AS/105/211).
Note (4): We consider a radio spectrum to be flat if any portion of its
spectrum in the range 0.6-22GHz has a spectral index flatter than -0.5
and steep if the radio spectral index is steeper than -0.5 over this
entire region.
Note (5): According to Mattox et al. (2001, Cat. J/ApJS/135/155) (first
letter) and Sowards-Emmerd et al. (2003, Cat. J/ApJ/590/109),
Sowards-Emmerd et al. (2004, Cat. J/ApJ/609/564) (second letter),
where:
Y = highly probable identification,
P = probable identification,
N = no identification;
1652+398 and 2255-282 are not identified in Mattox et al. (2001, Cat.
J/ApJS/135/155), Sowards-Emmerd et al. (2003, Cat. J/ApJ/590/109),
Sowards-Emmerd et al. (2004, Cat. J/ApJ/609/564), the highly
probable EGRET identifications are from Kataoka et al.
(1999ApJ...514..138K 1999ApJ...514..138K) and Bertsch (1998IAUC.6807....2B 1998IAUC.6807....2B), Macomb et al.
(1999ApJ...513..652M 1999ApJ...513..652M), Tornikoski et al. (1999AJ....118.1161T 1999AJ....118.1161T),
respectively.
Note (6): Member of VSOP (VLBI Space Observatory Programme) 5GHz AGN,
defined as follows:
A = VSOP AGN survey sample observed with VSOP;
B = VSOP AGN survey sample not yet observed with VSOP;
C = VSOP AGN survey sample being too faint to be observed with VSOP
(Horiuchi et al. (2004, Cat. J/ApJ/616/110) have analyzed sample
members A and C; in the latter case, 5 GHz VLBA data only were used);
PR = Pearson-Readhead VSOP survey sample Lister et al. (2001ApJ...562..208L 2001ApJ...562..208L).
Note (7): Paper reporting on fast variations from the source on the time
scale less than 2-3 days. The reference number followed by "(b)" if
the modulation index m>0.02 is reported in the paper.
1 = Quirrenbach et al. (1992A&A...258..279Q 1992A&A...258..279Q);
2 = Quirrenbach et al. (2000A&AS..141..221Q 2000A&AS..141..221Q);
3 = Kedziora-Chudczer et al. (2001, Cat. J/MNRAS/325/1411);
4 = Kraus et al. (2003A&A...401..161K 2003A&A...401..161K);
5 = Lovell et al. (2003ApJS..155...27L 2003ApJS..155...27L);
6 = Ojha et al. (2004, Cat. J/ApJ/614/607);
7 = Bignall et al. (2002PASA...19...29B 2002PASA...19...29B).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- IAU The IAU (B1950.0) name
10- 19 A10 "YYYY/MM/DD" ObsDate Date of observation
21- 25 F5.2 Jy Stot Filled-aperture (single antenna) flux
density
27- 31 F5.2 Jy Sclean Total CLEAN flux density of a VLBA map
33- 37 F5.2 Jy Sunres ? Flux density from the most compact
component of a VLBA map
39- 43 F5.2 Jy Score ? Flux density for a VLBA core component
in a model
45 A1 --- l_MajAxis Limit flag on MajAxis
46- 49 F4.2 mas MajAxis ? FWHM major axis of a VLBA core component
51 A1 --- l_MinAxis Limit flag on MinAxis
52- 55 F4.2 mas MinAxis ? FWHM minor axis for a VLBA core component
57- 59 I3 deg PA [-90/90]? Position angle of the major axis
of a VLBA core component
61 A1 --- l_Tb Limit flag on Tb
62- 69 E8.2 K Tb ? Brightness temperature of VLBA core
component
71- 74 E4.2 --- Comp ? Median value of SVLBA/Stot over all
available epochs (compactness at arcsecond
scales)
76- 79 I4 deg PAjet ? Position angle of the jet defined from
multi-epoch observations
81- 82 I2 --- Nobs ? Number of epochs of observations
84- 85 I2 --- Nep ? Number of epochs when source VLBA core
component is unresolved at least in one
direction
--------------------------------------------------------------------------------
History:
From electronic version of the journal
References:
Kellerman et al., Paper I 1998AJ....115.1295K 1998AJ....115.1295K
Zensus et al, Paper II 2002AJ....124..662Z 2002AJ....124..662Z
Kellerman et al., Paper III 2004ApJ...609..539K 2004ApJ...609..539K, Cat. J/ApJ/609/539
(End) Greg Schwarz [AAS], Marianne Brouty [CDS] 11-Apr-2006