J/AJ/146/120 MOJAVE. X. Parsec-scale kinematics of AGNs (Lister+, 2013)
MOJAVE. X. Parsec-scale jet orientation variations and superluminal motion in
active galactic nuclei.
Lister M.L., Aller M.F., Aller H.D., Homan D.C., Kellermann K.I.,
Kovalev Y.Y., Pushkarev A.B., Richards J.L., Ros E., Savolainen T.
<Astron. J., 146, 120 (2013)>
=2013AJ....146..120L 2013AJ....146..120L
ADC_Keywords: Active gal. nuclei ; BL Lac objects ; QSOs ; Radio sources ;
Proper motions ; Redshifts ; Radio continuum
Keywords: BL Lacertae objects: general - galaxies: active - galaxies: jets -
quasars: general - radio continuum: galaxies
Abstract:
We describe the parsec-scale kinematics of 200 active galactic nucleus
(AGN) jets based on 15GHz Very Long Baseline Array (VLBA) data
obtained between 1994 August 31 and 2011 May 1. We present new VLBA 15
GHz images of these and 59 additional AGNs from the MOJAVE and 2cm
Survey programs. Nearly all of the 60 most heavily observed jets show
significant changes in their innermost position angle over a 12-16yr
interval, ranging from 10° to 150° on the sky, corresponding
to intrinsic variations of ∼0.5° to ∼2°. The BL Lac jets show
smaller variations than quasars. Roughly half of the heavily observed
jets show systematic position angle trends with time, and 20 show
indications of oscillatory behavior. The time spans of the data sets
are too short compared to the fitted periods (5-12yr), however, to
reliably establish periodicity. The rapid changes and large jumps in
position angle seen in many cases suggest that the superluminal AGN
jet features occupy only a portion of the entire jet cross section and
may be energized portions of thin instability structures within the
jet. We have derived vector proper motions for 887 moving features in
200 jets having at least five VLBA epochs. For 557 well-sampled
features, there are sufficient data to additionally study possible
accelerations. We find that the moving features are generally
non-ballistic, with 70% of the well-sampled features showing either
significant accelerations or non-radial motions. Inward motions are
rare (2% of all features), are slow (<0.1mas/yr), are more prevalent
in BL Lac jets, and are typically found within 1mas of the unresolved
core feature. There is a general trend of increasing apparent speed
with distance down the jet for both radio galaxies and BL Lac objects.
In most jets, the speeds of the features cluster around a
characteristic value, yet there is a considerable dispersion in the
distribution. Orientation variations within the jet cannot fully
account for the dispersion, implying that the features have a range of
Lorentz factor and/or pattern speed. Very slow pattern speed features
are rare, comprising only 4% of the sample, and are more prevalent in
radio galaxy and BL Lac jets. We confirm a previously reported upper
envelope to the distribution of speed versus beamed luminosity for
moving jet features. Below 1026W/Hz there is a fall-off in maximum
speed with decreasing 15GHz radio luminosity. The general shape of the
envelope implies that the most intrinsically powerful AGN jets have a
wide range of Lorentz factors up to ∼40, while intrinsically weak jets
are only mildly relativistic.
Description:
We present new VLBA 15GHz images of the original 135 source MOJAVE
flux-density-limited sample (Lister et al., 2009, cat. J/AJ/137/3718,
Paper V) obtained between 2007 September 6 and 2011 May 1.
We also present VLBA images of 124 additional AGNs from three new AGN
jet samples, based on 15GHz Very Long Baseline Array (VLBA) data
obtained between 1994 August 31 and 2011 May 1 from the NRAO archive
(http://archive.nrao.edu/) and the MOJAVE program (Lister et al.,
2009, cat. J/AJ/137/3718, Paper V). These include a complete
radio-selected sample above 1.5Jy, a complete γ-ray-selected
sample (Lister et al., 2011, cat. J/ApJ/742/27), and a representative
low-luminosity AGN jet sample. The latter is drawn from the VLBA
Calibrator Survey (Beasley et al., 2002, cat. J/ApJS/141/13; Fomalont
et al., 2003, cat. J/AJ/126/2562; Petrov et al., 2005, cat.
J/AJ/129/1163; Petrov et al., 2006, cat. J/AJ/131/1872; Kovalev et
al., 2007, cat. J/AJ/133/1236; Petrov et al., 2008, cat.
J/AJ/136/580).
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 92 259 General properties of AGNs in the combined samples
table3.dat 72 1753 Summary of 15 GHz image parameters
table4.dat 62 22923 Fitted jet components
table5.dat 140 887 Kinematic fit properties of jet components
table6.dat 102 547 Acceleration fit properties of jet components
notes.dat 695 36 Notes
refs.dat 53 183 References
--------------------------------------------------------------------------------
See also:
VII/258 : Quasars and Active Galactic Nuclei (13th Ed.) (Veron+ 2010)
J/A+A/538/A26 : BL Lac objects beyond z=1.3 (Rau+, 2012
J/ApJS/199/31 : Fermi LAT second source catalog (2FGL) (Nolan+, 2012)
J/A+A/545/A113 : MOJAVE IX. Core shift effects (Pushkarev+, 2012)
J/AJ/144/105 : MOJAVE. VIII. Faraday rotation in AGN jets. (Hovatta+, 2012)
J/ApJ/742/27 : 15GHz and jet properties of MOJAVE blazars (Lister+, 2011)
J/ApJ/722/L7 : Fermi/LAT detected MOJAVE AGNs (Pushkarev+, 2010)
J/ApJ/710/764 : Extended radio emission in MOJAVE blazars (Kharb+, 2010)
J/ApJ/706/1253 : MOJAVE VII. Blazar jet acceleration (Homan+, 2009)
J/AJ/138/1874 : MOJAVE. VI. Kinematic analysis of blazar jets (Lister+, 2009)
J/AJ/137/3718 : 15GHz monitoring of AGN jets with VLBA (Lister+, 2009)
J/AJ/136/580 : Sixth VLBA calibrator survey: VCS6 (Petrov+, 2008)
J/ApJS/171/376 : MOJAVE. III. VLA 1.4GHz images (Cooper+, 2007)
J/AJ/133/1236 : Fifth VLBA calibrator survey: VCS5 (Kovalev+, 2007)
J/AJ/131/1262 : AGN jets circular polarization images at 15GHz (Homan+, 2006)
J/AJ/131/1872 : Fourth VLBA calibrator survey: VCS4 (Petrov+, 2006)
J/AJ/130/1389 : Linear polarization of AGN jets at 15GHz (Lister+, 2005)
J/AJ/130/1418 : AGN jet kinematics (Jorstad+, 2005)
J/AJ/129/1163 : Third VLBA calibrator survey: VCS3 (Petrov+, 2005)
J/ApJ/609/539 : Kinematics of parsec-scale radio jets (Kellermann+, 2004)
J/AJ/126/2562 : Second VLBA calibrator survey: VCS2 (Fomalont+, 2003)
J/ApJS/141/13 : VLBA calibrator survey: VCS1 catalog (Beasley+, 2002)
http://archive.nrao.edu/ : NRAO archive
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- Name Source name (HHMM+DDd, B1950)
10 A1 --- n_Name [a] Indicates a known TeV emitter (1)
12- 27 A16 --- OName Alternate name
29- 41 A13 --- 2FGL Name in the 2FGL catalog (JHHMM.m+DDMM) (2)
43- 50 F8.6 --- z [0.00436/3.396]? Redshift
52- 84 A33 --- r_z Reference for z and O; in refs.dat file
86 A1 --- O Optical classification (3)
88- 92 A5 --- Sample Sample membership (4)
--------------------------------------------------------------------------------
Note (1): (http://tevcat.uchicago.edu).
Note (2): Fermi LAT second source catalog (Nolan et al., 2012, cat.
J/ApJS/199/31).
Note (3): Optical classification as follows:
B = BL Lac;
Q = Quasar;
G = Radio galaxy;
N = Narrow Line Seyfert 1;
U = Unidentified.
Note (4): Sample as follows:
G = 1FM γ-ray selected sample (Lister et al., 2011, J/ApJ/742/27);
R = MOJAVE 1.5Jy sample;
L = Low-luminosity sample (drawn from the VLBA Calibrator Survey: Beasley et
al., 2002, cat. J/ApJS/141/13; Fomalont et al., 2003, cat.
J/AJ/126/2562; Petrov et al., 2005, cat. J/AJ/129/1163; Petrov et al.,
2006, cat. J/AJ/131/1872; Kovalev et al., 2007, cat. J/AJ/133/1236;
Petrov et al., 2008, cat. J/AJ/136/580).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- Name Source name (HHMM+DDd, B1950)
10- 20 A11 "Y:M:D" ObsDate Date of Very Long Baseline Array (VLBA)
observation
22- 28 A7 --- Code VLBA experiment code
30 A1 --- n_Code [ab] Configuration peculiarity (1)
32- 35 F4.1 GHz Freq [15.1/15.4] Observing frequency
37- 40 F4.2 mas a FWHM major axis of restoring beam
42- 45 F4.2 mas b FWHM minor axis of restoring beam
47- 49 I3 deg PA [-88/89] Position angle of major restoring
beam axis
51- 56 F6.3 Jy Itot [0.049/27.629] Total flux density
58- 60 F3.1 mJy rms RMS noise level of image (in mJy/beam)
62- 65 F4.1 mJy Ibase Lowest I contour (in mJy/beam)
67- 72 A6 --- Fig Figure number (2.1 to 2.1753)
--------------------------------------------------------------------------------
Note (1): Flag on Code as follows:
a = Full polarization MOJAVE epoch;
b = 2cm VLBA Survey (Kellermann et al., 1998AJ....115.1295K 1998AJ....115.1295K) epoch.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- Name Source name (HHMM+DDd, B1950)
10- 11 I2 --- Comp [0/56] Component identification number (1)
13 A1 --- f_Comp [a] Individual component epoch not used in
kinematic fits
15- 25 A11 "Y:M:D" Date Date of VLBA observation
27- 32 F6.3 Jy FI ? Flux density of component (at 15GHz)
34 A1 --- n_FI [N] Note on FI (in notes.dat file)
36- 40 F5.2 mas Off ? Position offset of component (2)
42- 46 F5.1 deg PA ? Position angle of component (3)
48- 51 F4.2 mas a ? FWHM major axis of fitted Gaussian
53- 56 F4.2 --- b/a [0/1]? Axial ratio of fitted Gaussian
58- 60 I3 deg PAm [0/360] Major axis position angle of fitted
Gaussian
62 A1 --- R [YN] Robust component flag (Y=Yes, N=No)
--------------------------------------------------------------------------------
Note (1): zero indicates core component.
Note (2): From the core component (or map center for the core component entries)
Note (3): With respect to the core component (or map center for the core
component entries).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table5.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- Name Source name (HHMM+DDd, B1950)
10- 11 I2 --- Comp [1/49] Component identification number
13 A1 --- f_Comp [d] Component has a slow pattern speed
15- 17 I3 --- Nep [5/115] Number of fitted epochs
19- 22 I4 mJy [3/6994] Mean 15GHz flux density
24- 28 F5.2 mas Mean distance from core component
30- 35 F6.2 pc ? Mean projected distance from core component
37- 41 F5.1 deg Mean position angle <θ> with respect to
core component
43- 48 F6.2 deg PA Position angle φ of velocity vector
50- 55 F6.2 deg e_PA Uncertainty in PA
57- 58 A2 --- f_PA [c? ] Component shows significant inward
motion (1)
60- 65 F6.2 deg Off Offset between and PA |<θ>-φ|
67- 72 F6.2 deg e_Off Uncertainty in Off
74- 75 A2 --- n_Off [b? ] Component shows significant non-radial
motion (1)
77- 83 F7.2 uas/yr pm Angular proper motion
85- 90 F6.2 uas/yr e_pm Uncertainty in pm
92 A1 --- n_pm [a] Component shows significant accelerated
motion
94-100 F7.4 c beta ? Fitted speed β in units of light speed
102-107 F6.4 c e_beta ? Uncertainty in beta
109-116 F8.3 yr Tej [1931/2011]? Fitted ejection date
118-123 F6.3 yr e_Tej ? Uncertainty in Tej
125-131 F7.2 yr Tmid [1996/2011] Date of reference (middle)
epoch used for fit
133-136 I4 uas eRA Right Ascension error of individual epoch
positions
138-140 I3 uas eDE Declination error of individual epoch
positions
--------------------------------------------------------------------------------
Note (1): A question mark indicates a non-radially moving component for which
an inward/outward determination is uncertain due to its slow angular speed.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table6.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- Name Source name (HHMM+DDd, B1950)
10- 11 I2 --- Comp [1/48] Component identification number
13 A1 --- f_Comp Component shows significant accelerated motion
15- 20 F6.2 deg pmPA Proper motion position angle
22- 27 F6.2 deg e_pmPA Uncertainty in pmRA
29- 35 F7.2 uas/yr pm Angular proper motion µ
37- 42 F6.2 uas/yr e_pm Uncertainty in pm
44- 50 F7.2 uas/yr2 dpm1 Angular acceleration perpendicular to velocity
direction (dµ/dt)⊥
52- 57 F6.2 uas/yr2 e_dpm1 Uncertainty in dpm1
59- 65 F7.2 uas/yr2 dpm2 Angular acceleration parallel to velocity
direction (dµ/dt)||
67- 72 F6.2 uas/yr2 e_dpm2 Uncertainty in dpm2
74- 80 F7.4 yr-1 a1 ? Relative acceleration in direction
perpendicular to fitted velocity vector (1)
82- 87 F6.4 yr-1 e_a1 ? Uncertainty in a1
89- 95 F7.4 yr-1 a2 ? Relative acceleration in direction (1)
parallel to fitted velocity vector
97-102 F6.4 yr-1 e_a2 ? Uncertainty in a2
--------------------------------------------------------------------------------
Note (1): relative acceleration is defined as
dη/dt = (1+z)(dµ/dt)/µ
--------------------------------------------------------------------------------
Byte-by-byte Description of file: notes.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- Name IAU name (HHMM+DDd, B1950)
10-695 A686 --- Text Text of note on individual sources
--------------------------------------------------------------------------------
Byte-by-byte Description of file: refs.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 33 A33 --- Ref Reference
35- 53 A19 --- BibCode Bibliographic code
--------------------------------------------------------------------------------
History:
From electronic version of the journal
References:
Lister et al. Paper I. 2005AJ....130.1389L 2005AJ....130.1389L Cat. J/AJ/130/1389
Homan et al. Paper II. 2006AJ....131.1262H 2006AJ....131.1262H Cat. J/AJ/131/1262
Cooper et al. Paper III. 2007ApJS..171..376C 2007ApJS..171..376C Cat. J/ApJS/171/376
Cara et al. Paper IV. 2008ApJ...674..111C 2008ApJ...674..111C
Lister et al. Paper V. 2009AJ....137.3718L 2009AJ....137.3718L Cat. J/AJ/137/3718
Lister et al. Paper VI. 2009AJ....138.1874L 2009AJ....138.1874L Cat. J/AJ/138/1874
Homan et al. Paper VII. 2009ApJ...706.1253H 2009ApJ...706.1253H Cat. J/ApJ/706/1253
Hovatta et al. Paper VIII. 2012AJ....144..105H 2012AJ....144..105H Cat. J/AJ/144/105
Pushkarev et al. Paper IX. 2012A&A...545A.113P 2012A&A...545A.113P Cat. J/A+A/545/A113
Hovatta et al. Paper XI. 2014AJ....147..143H 2014AJ....147..143H Cat. J/AJ/147/143
Homan et al. Paper XII. 2015ApJ...798..134H 2015ApJ...798..134H Cat. J/ApJ/798/134
Lister et al. Paper XIII. 2016AJ....152...12L 2016AJ....152...12L Cat. J/AJ/152/12
Pushkarev et al. Paper XIV. 2017MNRAS.468.4992P 2017MNRAS.468.4992P Cat. J/MNRAS/468/4992
Lister et al. Paper XV. 2018ApJS..234...12L 2018ApJS..234...12L Cat. J/ApJS/234/12
Hodge et al. Paper XVI. 2018ApJ...862..151H 2018ApJ...862..151H Cat. J/ApJ/862/151
Lister et al. Paper XVII. 2019ApJ...874...43L 2019ApJ...874...43L Cat. J/ApJ/874/43
Lister et al. Paper XVIII. 2021ApJ...923...30L 2021ApJ...923...30L Cat. J/ApJ/923/30
Homan et al. Paper XIX. 2021ApJ...923...67H 2021ApJ...923...67H Cat. J/ApJ/923/67
Pushkarev et al. Paper XX. 2023MNRAS.520.6053P 2023MNRAS.520.6053P
(End) Greg Schwarz [AAS], Sylvain Guehenneux [CDS] 28-Jul-2014