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J/AJ/130/1418            AGN jet kinematics                     (Jorstad+, 2005)

Polarimetric observations of 15 active galactic nuclei at high frequencies: jet kinematics from bimonthly monitoring with the Very Long Baseline Array. Jorstad S.G., Marscher A.P., Lister M.L., Stirling A.M., Cawthorne T.V., Gear W.K., Gomez J.L., Stevens J.A., Smith P.S., Forster J.R., Robson E.I. <Astron. J., 130, 1418-1465 (2005)> =2005AJ....130.1418J
ADC_Keywords: Radio sources ; BL Lac objects ; Active gal. nuclei ; QSOs ; Polarization Keywords: BL Lacertae objects: individual (3C 66A, OJ 287, 1803+784, 1823+568, BL Lacertae) - galaxies: active - galaxies: individual (3C 111, 3C 120) - galaxies: jets - quasars: individual (0420-014, 0528+134, 3C 273, 3C 279, PKS 1510-089, 3C 345, CTA 102, 3C 454.3) Abstract: We present total and polarized intensity images of 15 active galactic nuclei obtained with the Very Long Baseline Array at 7mm (43GHz) wavelength at 17 epochs from 1998 March to 2001 April. At some epochs the images are accompanied by nearly simultaneous polarization measurements at 3mm (86GHz) with the Berkeley-Illinois-Maryland Association (BIMA) array (Hat Creek, California), 1.35/0.85mm (230/350GHz) with the James Clerk Maxwell Telescope (JCMT; using SCUBA and its polarimeter, and at the Steward Observatory 1.5m telescope (Mount Lemmon, Arizona) with the Two-Holer Polarimeter/Photometer over an effective wavelength range of ∼6000-7000Å. Here we analyze the 7mm images to define the properties of the jets of two radio galaxies, five BL Lac objects, and eight quasars on angular scales ≳0.1mas. We determine the apparent velocities of 106 features in the jets. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 50 15 Sample and parameters of maps shown in Figs. 1-15 table5.dat 89 116 Jet velocities
See also: J/ApJ/609/539 : Kinematics of parsec-scale radio jets (Kellermann+, 2004) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 8 A8 --- Name Source name 10- 11 A2 --- Type Object type (1) 13- 17 F5.3 --- z Redshift 19- 22 F4.2 mas Size1 Beam size 23 A1 --- --- [x] 24- 27 F4.2 mas Size2 Beam size 29- 31 I3 deg PA [-90,90] Beam position angle 33- 37 I5 mJy Ipeak Peak of the total intensity at 43GHz (in units of mJy/beam) 39- 42 I4 mJy Ippeak Peak of the polarized intensity at 43GHz (in units of mJy/beam) 44- 47 F4.1 mJy Imin Lowest level of the total intensity at 43GHz (in units of mJy/beam) 49- 50 I2 mJy Ipmin Lowest level of the polarized intensity at 43GHz (in units of mJy/beam)
Note (1): Object type, defined as follows: BL = BL Lac, Q = QSO, RG = Radio Galaxy.
Byte-by-byte Description of file: table5.dat
Bytes Format Units Label Explanations
1- 8 A8 --- Name Source name (1) 10- 12 A3 --- Knot Knot identification 15- 16 I2 --- o_Knot Number of epochs Knot observed 18- 21 F4.2 Jy <S> Average total flux density of the knot at 43GHz 23- 26 F4.2 mas <R> Average angular core distance of the knot 28- 33 F6.1 deg <Theta> Position angle of the knot relative to the VLBI core A0 (2) 35- 38 F4.1 deg e_<Theta> Uncertainty in <Theta> 40 I1 --- l Polynomial order (3) 42 A1 --- f_l [*] Approximation by a straight line (4) 44- 49 F6.1 deg <Phi> Average position angle of the velocity vector 51- 54 F4.1 deg e_<Phi> Uncertainty in <Phi> 56- 59 F4.2 mas/yr <mu> Average proper motion 61- 64 F4.2 mas/yr e_<mu> Uncertainty in <mu> 66- 70 F5.2 --- <beta> Average apparent speed (5) 72- 75 F4.2 --- e_<beta> Uncertainty in <beta> 77- 83 F7.2 yr T0 ? Ejection time (epoch of zero separation) 85- 89 F5.2 yr e_T0 ? Uncertainty in T0
Note (1): Recalculation of component properties based on combined data from this work and previously published results (see text in Appendix A). Note (2): For each image we identify a component, A0, as the VLBI core. For all sources A0 is located at one end of the jet, although it is not always the brightest feature. The position of the core in right ascension x and declination y is defined as x=0, y=0. Note (3): The thorough sequences of images allow us to search for acceleration/ deceleration of the jet flow and nonballistic projected trajectories. We fit the (x, y) positions of a component over N epochs by different polynomials of order l: x(ti)=a0+a1(ti-tmid)+a2(ti-tmid)2+...+al(ti-tmid)l y(ti)=b0+b1(ti-tmid)+b2(ti-tmid)2+...+bl(ti-tmid)l. Note (4): In a few cases the χ2 test is not satisfied even by polynomials of order 4. An increase in the order of the polynomial does not improve the situation, since, given the limited number of observations, the number of degrees of freedom becomes too small. Such cases are approximated by a straight line with special consideration for uncertainties in the (x, y) values. Note (5): Calculated in units of the speed of light, c, using the average proper motion, <mu>, and an inhomogeneous Friedmann-Lemaitre-Robertson-Walker cosmology, with Ωm=0.3, ΩΛ=0.7, and Hubble constant H0=70km/s/Mpc (Kantowski, Kao & Thomas 2000ApJ...545..549K).
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Marianne Brouty [CDS] 22-Feb-2006
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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