J/ApJ/923/67 MOJAVE. XIX. Brightness temperatures of jets (Homan+, 2021)
MOJAVE.
XIX. Brightness temperatures and intrinsic properties of blazar jets.
Homan D.C., Cohen M.H., Hovatta T., Kellermann K.I., Kovalev Y.Y.,
Lister M.L., Popkov A.V., Pushkarev A.B., Ros E., Savolainen T.
<Astrophys. J., 923, 67 (2021)>
=2021ApJ...923...67H 2021ApJ...923...67H
ADC_Keywords: Active gal. nuclei; BL Lac objects; Radio sources; Surveys;
Gamma rays; Redshifts; Energy distributions
Keywords: Active galaxies ; Galaxy jets ; Radio galaxies ; Quasars ;
BL Lacertae objects ; Surveys
Abstract:
We present multiepoch, parsec-scale core brightness temperature
observations of 447 active galactic nucleus (AGN) jets from the MOJAVE
and 2cm Survey programs at 15GHz from 1994 to 2019. The brightness
temperature of each jet over time is characterized by its median value
and variability. We find that the range of median brightness
temperatures for AGN jets in our sample is much larger than the
variations within individual jets, consistent with Doppler boosting
being the primary difference between the brightness temperatures of
jets in their median state. We combine the observed median brightness
temperatures with apparent jet speed measurements to find the typical
intrinsic Gaussian brightness temperature of 4.1(±0.6)x1010K,
suggesting that jet cores are at or below equipartition between
particle and magnetic field energy in their median state. We use this
value to derive estimates for the Doppler factor for every source in
our sample. For the 309 jets with both apparent speed and brightness
temperature data, we estimate their Lorentz factors and viewing angles
to the line of sight. Within the BL Lac optical class, we find that
high-synchrotron-peaked BL Lacs have smaller Doppler factors, lower
Lorentz factors, and larger angles to the line of sight than
intermediate and low-synchrotron-peaked BL Lacs. We confirm that AGN
jets with larger Doppler factors measured in their parsec-scale radio
cores are more likely to be detected in γ rays, and we find a
strong correlation between γ-ray luminosity and Doppler factor
for the detected sources.
Description:
Our sample consists of the 447 AGN recently studied by the Monitoring
Of Jets in Active galactic nuclei with VLBA Experiments (MOJAVE)
program for kinematics in Paper XVIII (Lister+ 2021, J/ApJ/923/30), of
which 206 are members of the MOJAVE 1.5Jy quarter-century (QC)
flux-density-limited sample selected on the basis of parsec-scale jet
emission (e.g., Lister+ 2019, J/ApJ/874/43).
For each source we measure its core brightness temperature as
described in Section 2.1 in all the 15GHz VLBA epochs analyzed by our
program through 2019 August 6.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 113 447 Source properties
table2.dat 110 7728 Brightness temperature fitting results
table3.dat 117 447 Brightness temperatures and apparent speeds
table4.dat 63 447 Doppler factors and derived properties
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See also:
II/174 : IRAS 2Jy Redshift Survey Data File (Strauss+ 1992)
II/282 : The SDSS Photometric Catalog, Release 6 (Adelman-McCarthy+, 2007)
III/175 : Optical spectroscopy of radio sources (Stickel+, 1989-94)
VIII/34 : Parkes Half-Jansky Flat-Spectrum Sample (Drinkwater + 1997)
VII/249 : 6dF-DR2 Galaxy Survey (Jones+, 2005)
VII/259 : 6dF galaxy survey final redshift release (Jones+, 2009)
VII/260 : The SDSS-DR7 quasar catalog (Schneider+, 2010)
VII/279 : SDSS quasar catalog: twelfth data release (Paris+, 2017)
VII/286 : SDSS quasar catalog, fourteenth data release (Paris+, 2018)
J/PASP/97/932 : 3CR Source Identifications (Spinrad+, 1985)
J/A+AS/80/103 : Optical spectroscopy of 1Jy, S4 and S5 sources (Stickel+ 1989)
J/A+AS/96/389 : Warm IRAS sources. II. (de Grijp+, 1992)
J/A+AS/97/483 : Optical spectroscopy of 1Jy, S4 and S5 sources (Stickel+ 1993)
J/A+AS/98/393 : 1Jy BL Lac Objects: Observational Data (Stickel+ 1993)
J/A+AS/100/395 : Optical spectroscopy of 1Jy, S4 and S5 sources (Stickel+ 1993)
J/A+AS/105/67 : Optical spectroscopy of 1Jy, S4 and S5 sources (Stickel+ 1994)
J/A+AS/105/211 : Optical identification status of 1Jy catalogue (Stickel+ 1994)
J/A+AS/110/469 : AGN from the RASS (Bade+, 1995)
J/AJ/109/14 : Optical spectroscopy of Abell clusters. I. (Owen+ 1995)
J/AJ/112/1803 : Large Scale Structure (Marzke+ 1996)
J/A+AS/115/1 : Optical identification of S5 catalog (Stickel+, 1996)
J/A+AS/115/11 : Optical identifications of radio sources (Stickel+, 1996)
J/AJ/115/1253 : Deep X-Ray Radio Blazar Survey (DXRBS). I. (Perlman+ 1998)
J/PASP/111/438 : Updated Zwicky catalog (UZC) (Falco+, 1999)
J/ApJ/525/127 : RGB sample of BL Lacertae objects (Laurent-Muehleisen+, 1999)
J/ApJS/121/287 : The CfA2S catalog (Huchra+, 1999)
J/ApJS/126/133 : The FIRST bright quasar survey. II. (White+, 2000)
J/ApJS/145/199 : Opt. spectroscopic atlas of low-redshift AGN (Marziani+, 2003)
J/ApJ/590/109 : Gamma-ray blazar in northern sky (Sowards-Emmerd+, 2003)
J/ApJS/150/181 : Redshifts of 110 radio-loud AGNs (Eracleous+, 2004)
J/AJ/130/1389 : Linear polarization of AGN jets at 15GHz (Lister+, 2005)
J/AJ/130/1418 : AGN jet kinematics (Jorstad+, 2005)
J/AJ/130/2473 : Fine-scale structure in 250 sources at 15GHz (Kovalev+, 2005)
J/ApJ/626/95 : Gamma-ray blazar candidates (Sowards-Emmerd+, 2005)
J/A+A/445/441 : SED of BL Lacertae objects (Nieppola+, 2006)
J/A+A/463/97 : Optical observations of GPS radio sources (Labiano+, 2007)
J/A+A/476/L17 : 86 and 43GHz observations of NRAO 150 (Agudo+, 2007)
J/ApJ/667/673 : FIRST-2MASS red quasar survey (Glikman+, 2007)
J/ApJS/175/97 : CGRaBS: survey of γ-ray blazar cand. (Healey+, 2008)
J/A+A/488/867 : Synchrotron peak frequency of 135 AGN (Nieppola+, 2008)
J/AJ/138/1874 : MOJAVE. VI. Kinematic analysis of blazar jets (Lister+, 2009)
J/ApJS/180/67 : Phot. selection of quasars from SDSS. II. (Richards+, 2009)
J/ApJ/715/429 : First Fermi-LAT AGN catalog (1LAC) (Abdo+, 2010)
J/AJ/139/390 : Opt. selected BL Lac objects from SDSS-DR7 (Plotkin+, 2010)
J/ApJ/740/98 : Synchroton peak for blazars and radio galaxies (Meyer+, 2011)
J/ApJ/742/27 : 15GHz and jet properties of MOJAVE blazars (Lister+, 2011)
J/ApJ/743/171 : The 2LAC catalog (Ackermann+, 2011)
J/ApJS/194/29 : Observations of blazars at 15GHz (Richards+, 2011)
J/ApJS/199/26 : The 2MASS Redshift Survey (2MRS) (Huchra+, 2012)
J/A+A/538/A26 : BL Lac objects beyond z=1.3 (Rau+, 2012)
J/ApJ/748/49 : Optical spectroscopy of 1LAC broad-line blazars (Shaw+, 2012)
J/MNRAS/430/2464 : The CLASS BL Lac sample (Marcha+, 2013)
J/ApJ/767/14 : MASIV survey III. Optical identifications (Pursimo+, 2013)
J/ApJ/764/135 : Spectroscopic redshifts of BL Lac objects (Shaw+, 2013)
J/ApJ/810/14 : Third catalog of LAT-detected AGNs (3LAC) (Ackermann+, 2015)
J/ApJ/798/134 : MOJAVE. XII. Acceleration of blazar jets (Homan+, 2015)
J/MNRAS/450/3568 : Non-Fermi blazar sample (Xiong+, 2015)
J/MNRAS/462/3180 : 3FGL Blazar of Unknown Type classification (Chiaro+, 2016)
J/ApJS/232/18 : The third Fermi-LAT >10GeV catalog (3FHL) (Ajello+, 2017)
J/A+A/598/A17 : The 2WHSP catalog (Chang+, 2017)
J/ApJ/846/98 : Jet kinematics of blazars at 43GHz with VLBA (Jorstad+, 2017)
J/ApJS/233/3 : The VLBA Extragalactic Proper Motion Cat. (Truebenbach+, 2017)
J/ApJ/866/137 : Bright blazars variability brightness temp. (Liodakis+, 2018)
J/ApJS/234/12 : MOJAVE XV. VLBA obs. of AGN jets 1996-2016 (Lister+, 2018)
J/ApJ/853/68 : Multi-epoch VLBA imaging of 20 Tev blazars (Piner+, 2018)
J/A+A/632/A77 : 3HSP blazars catalog (Chang+, 2019)
J/ApJ/874/43 : MOJAVE. XVII. pc-scale jet kinematics of AGNs (Lister+, 2019)
J/ApJ/892/105 : 4th catalog of Fermi LAT-detected AGNs (4LAC) (Ajello+, 2020)
J/MNRAS/495/3576 : AGN jet shape transition geometry (Kovalev+, 2020)
J/A+A/643/A103 : Fermi-LATi low-energy counterparts (Pena-Herazo+, 2020)
J/A+A/650/A83 : Radio flux densities of neutrino associations (Hovatta+, 2021)
J/ApJ/923/30 : MOJAVE. XVIII. Bright radio-loud active AGNs (Lister+, 2021)
http://www.cv.nrao.edu/MOJAVE/ : MOJAVE program home page
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- ID Source name in truncated B1950.0 coordinates
10- 29 A20 --- Alias Alias name
31- 38 F8.6 --- z [0.004/3.4]? Redshift
40- 40 A1 --- Class Optical Class (1)
42- 42 A1 --- MOJ1.5 [YN] Member of the MOJAVE 1.5Jy QC sample
44- 46 A3 --- SED SED class (2)
48- 52 F5.2 [Hz] nu-peak [11.8/17.7]? log of SED Peak in Observer Frame
54- 58 F5.2 [10-7W] Lgamma [41.7/49]? log of γ-ray luminosity;
see Section 3.1.1
60- 85 A26 --- Ref1 Reference (bibcode) for Redshift+Optical
Classification
87-113 A27 --- Ref2 Reference (bibcode) for SED properties
--------------------------------------------------------------------------------
Note (1): Optical Class as follows:
Q = Quasar;
B = BL Lac;
G = radio galaxy;
N = narrow-line Seyfert 1;
U = unknown.
Note (2): SED Class -- LSP/ISP/HSP = Low/Intermediate/High Synchrotron Peaked.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- ID Source name in truncated B1950.0
coordinates
10- 20 A11 "Y/M/D" Epoch Epoch
22- 26 F5.2 GHz nu-obs [14.24/15.5] Central Observing Frequency
28- 31 F4.2 mas Bmaj [0.36/3] Naturally weighed beam, major
axis
33- 36 F4.2 mas Bmin [0.3/2] Naturally weighed beam, minor
axis
38- 42 F5.1 deg Bpa [-90/90] Naturally weighed beam, position
angle E of N
44- 47 F4.1 mas CX [-3/30.4] Center location of removed
clean component area
49- 52 F4.1 mas CY [-1.1/27.1] Center location of removed
clean component area
54- 57 F4.2 --- Cfact [1/2.81] Factor times beam dimensions
used for removing clean components
59- 65 F7.4 Jy SG [0.0028/28.43] Flux density of fitted
Gaussian
67 A1 --- l_Omega-maj Limit flag on Omega-maj
69- 74 F6.3 mas Omega-maj [0.024/1.52] Fitted Gaussian, major axis
76 A1 --- l_Omega-min Limit flag on Omega-min
78- 84 F7.4 mas Omega-min [0.008/0.9] Fitted Gaussian, minor axis
86- 90 F5.1 deg Omega-pa [-90/90] Fitted Gaussian, position angle,
E of N
92- 98 F7.3 mJy/beam sigma-rms [0.039/159] RMS residual noise (1)
100 A1 --- l_Tb Limit flag on Tb
102- 108 F7.3 [K] Tb [9/13.8] log of peak brightness
temperature (2)
110 A1 --- f_Tb Flag on Tb (G1)
--------------------------------------------------------------------------------
Note (1): RMS residual noise in an region twice the beam dimensions
centered at (CX, CY).
Note (2): Peak brightness temperature of the fitted Gaussian in rest frame
of host galaxy.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- ID Source name in truncated B1950.0 coordinates
10- 12 I3 --- N [5/180] Number of Epochs
14- 14 A1 --- l_Tb-min Limit flag on Tb-min
16- 21 F6.3 [K] Tb-min [9/12.5] log of minimum peak Gaussian
brightness temperature
23- 23 A1 --- f_Tb-min Flag on Tb-min (G1)
25- 25 A1 --- l_Tb-25 Limit flag on Tb-25
27- 32 F6.3 [K] Tb-25 [9.4/12.6] log of peak Gaussian brightness
temperature at 25% of distribution
34- 34 A1 --- f_Tb-25 Flag on Tb-25 (G1)
36- 36 A1 --- l_Tb-med Limit flag on Tb-med
38- 43 F6.3 [K] Tb-med [9.7/13] log of median peak Gaussian
brightness temperature
45- 45 A1 --- f_Tb-med Flag on Tb-med (G1)
47- 47 A1 --- l_Tb-75 Limit flag on Tb-75
49- 54 F6.3 [K] Tb-75 [9.8/13.3] log of peak Gaussian brightness
temperature at 75% of distribution
56- 56 A1 --- f_Tb-75 Flag on Tb-75 (G1)
58- 58 A1 --- l_Tb-max Limit flag on Tb-max
60- 65 F6.3 [K] Tb-max [9.9/13.8] log of maximum peak Gaussian
brightness temperature
67- 67 A1 --- f_Tb-max Flag on Tb-max (G1)
69- 69 A1 --- l_Var Limit flag on Var
71- 75 F5.3 --- Var [0.04/0.94]? Variability index of
Gaussian brightness temperature
77- 78 I2 --- Ns [1/51]? Number of robust speeds meeting
criteria (Section 2.2)
80- 85 F6.3 --- Beta-max [0.02/41.5]? Fastest apparent speed
87- 91 F5.3 --- e_Beta-max [0.002/8]? Uncertainty in Beta-max
93- 98 F6.3 --- Beta-med [0.012/34.8]? Median apparent speed
100-104 F5.3 --- e_Beta-med [0.002/5]? Uncertainty in Beta-med
106-111 F6.3 --- Beta-close [0.012/34.8]? Apparent speed of feature that
is closest to the core in its first
measured epoch
113-117 F5.3 --- e_Beta-close [0.002/7.3]? Uncertainty in Beta-close
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- ID Source name in truncated B1950.0 coordinates
10- 10 A1 --- l_Tb-med Limit flag on Tb-med
12- 17 F6.3 [K] Tb-med [9.7/13] log of median peak Gaussian
brightness temperature
19- 19 A1 --- f_Tb-med Flag on Tb-med (G1)
21- 26 F6.3 --- Beta-max [0.02/41.5]? Fastest apparent speed
28- 32 F5.3 --- e_Beta-max [0.002/8]? Uncertainty in Beta-max
34- 34 A1 --- l_delta Limit flag on delta
36- 41 F6.2 --- delta [0.13/195.1] Doppler factor (3)
43- 50 F8.3 --- Gamma [1/1787]? Lorentz factor derived from delta,
Beta-max
52- 57 F6.2 deg theta [0.02/145]? Angle to the line of sight
from delta, Beta-max
59- 63 F5.1 deg theta-src [1.8/179.1]? Angle to the line of sight
in the co-moving frame
--------------------------------------------------------------------------------
Note (3): Doppler factor assuming Tb,int=1010.609K as found in Section 2.2
--------------------------------------------------------------------------------
Global notes:
Note (G1): Flag as follows:
a = Lower limit value (z=0) only on account of unknown source redshift
--------------------------------------------------------------------------------
History:
From electronic version of the journal
* 17-Oct-2023:Insert into VizieR
* 11-Mar-2025: In VizieR, SimbadName for 0821+621 (row 156) has been
changed for QSO B0821+621 which is a very different source of
the alias "4C +62.12" given in Table 1 of Paper XVIII (J/ApJ/923/30)
from which the SimbadName has been retrieved.
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 & Lister 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
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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 This catalog
Pushkarev et al. Paper XX. 2023MNRAS.520.6053P 2023MNRAS.520.6053P
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 16-May-2023