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J/A+A/342/378       6 and 20cm flux densities of radio galaxies (Gurvits+ 1999)

The "angular size - redshift" relation for compact radio structures in quasars and radio galaxies Gurvits L.I., Kellermann K.I., Frey S. <Astron. Astrophys. 342, 378 (1999)> =1999A&A...342..378G (SIMBAD/NED BibCode)
ADC_Keywords: Active gal. nuclei ; QSOs ; Galaxies, radio ; Redshifts ; Radio sources ; VLBI Keywords: galaxies: active - galaxies: quasars: general - cosmology: observations - radio continuum: galaxies Abstract: We discuss the "angular size-redshift" relation for compact radio sources distributed over a wide range of redshifts 0.011≤z≤4.72. Our study is based on a sample of 330 5 GHz VLBI contour maps taken from the literature. Unlike extended source samples, the "angular size - redshift" relation for compact radio sources appears consistent with the predictions of standard Friedmann world models with q0≃0.5 without the need to consider evolutionary or selection effects due to a "linear size-luminosity" dependence. By confining our analysis to sources having a spectral index, -0.38≤α≤0.18, and a total radio luminosity, Lh2≥ 1026W/Hz (H0=100hkm/s/Mpc, q0=0.5 used as a numerical example), we are able to restrict the dispersion in the "angular size-redshift" relation. The best fitting regression analysis in the framework of the Friedmann-Robertson-Walker model gives the value of the deceleration parameter q0=0.21±0.30 if there are no evolutionary or selection effects due to a "linear size-luminosity", "linear size-redshift" or "linear size-spectral index" dependence. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 73 330 "VLBI angular size - z" for 330 sources refs.dat 153 86 References table1.tex 113 780 LaTeX version of table1 72 1342 PostScript version of table1
Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 8 A8 --- IAU IAU name (based on 1950 position) 10- 17 A8 --- Name Alternative name 19- 23 F5.3 --- z Redshift 25 A1 --- Type [BGQ] Type of the optical counterpart (1) 27- 31 F5.2 Jy S6cm Flux density at 6 cm from Gregory et al. (1996) unless otherwise stated. 32 A1 --- n_S6cm [q] Note on S6cm (2) 34- 38 F5.2 Jy S20cm ? Flux density at 20 cm (or alternative) from White and Becker (1992) unless otherwise stated 39 A1 --- n_S20cm [f-y] Note on S20cm (2) 41- 45 F5.2 --- SI Spectral index 47 A1 --- l_theta Symbol of an upper limit 48- 51 F4.1 mas theta Angular size 53 A1 --- Struc [CJLS] Structure code (3) 55- 58 A4 --- r_z Redshift reference in refs.dat file 60- 63 A4 --- r_S6cm 6cm flux density reference in refs.dat file 65- 68 A4 --- r_S20cm 20cm flux density reference in refs.dat file 70- 73 A4 --- r_VLBI VLBI reference in refs.dat file
Note (1): Q: quasar B: BL Lac object G: radio galaxy (including Seyfert galaxies of all types) Note (2): f: Spectral index calculated using S11=0.61Jy g: Spectral index calculated using S11=3.56Jy h: Spectral index calculated using S75=5.05Jy i: Spectral index calculated using S11=1.10Jy j: Spectral index calculated using S11=1.33Jy k: Spectral index calculated using S11=0.40Jy l: Spectral index calculated using S11=0.56Jy m: Spectral index calculated using S11=0.45Jy n: Spectral index calculated using S75=0.14Jy o: Spectral index calculated using S11=2.74Jy p: Spectral index calculated using S11=1.08Jy q: S6 and S20 values for the compact core component x: Spectral index calculated using S11=1.76Jy y: Spectral index calculated using S11=1.34Jy Note (3): Characteristic angular size (case C) or its upper limit (cases J, L, and S). Radio structure code: C: size between the core and the most distant 2%-component J: upper limit of θ along jet direction L: upper limit of θ along major axis of the beam S: upper limit of θ along minor axis of the beam
Byte-by-byte Description of file: refs.dat
Bytes Format Units Label Explanations
1- 4 A4 --- Ref Reference code 6- 24 A19 --- BibCode BibCode 26- 47 A22 --- Aut Author's name 49-153 A105 ---- Comm Comments
Acknowledgements: Leonid Gurvits
(End) Patricia Bauer [CDS] 04-Dec-1998
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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