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J/A+A/469/451       Radio continuum spectra of GPS galaxies  (Torniainen+, 2007)

Radio continuum spectra of gigahertz-peaked spectrum galaxies. Torniainen I., Tornikoski M., Lahteenmaki A., Aller M.F., Aller H.D., Mingaliev M.G. <Astron. Astrophys. 469, 451 (2007)> =2007A&A...469..451T
ADC_Keywords: Galaxies, radio ; QSOs Keywords: quasars: general ; radio continuum: galaxies Abstract: Recent studies have shown that a remarkable share of quasars classified in the literature as gigahertz-peaked spectrum (GPS) sources and high frequency peakers (HFPs) are actually flaring flat-spectrum sources or blazars. Thus, at least among the quasar-type samples, genuine GPS sources and HFPs seem to be rare. We have studied variability and the shape of the radio continuum spectra of a sample of 96 galaxy-type GPS sources and HFPs in order to find out whether there is a similar contamination in the galaxy-type samples. Description: Radio continuum spectral properties of a sample of 96 galaxy-type gigahertz-peaked spectrum (GPS) sources are presented. When available, also the redshifts of the sources are listed. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table2.dat 58 96 The sample of galaxy-type GPS sources
See also: J/A+AS/132/341 : ROSAT GPS optical identification (Motch+ 1998) J/A+AS/135/273 : 408MHz obs. of GPS sources from JVAS survey (Marecki+ 1999) J/A+A/369/380 : CSS/GPS radio sources VLA observations (Fanti+, 2001) J/A+A/463/97 : Optical observations of GPS radio sources (Labiano+, 2007) Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1- 8 A8 --- Source B1950 name of the source 10- 14 F5.3 --- z ? Redshift 15 A1 --- u_z [?] Uncertainty flag for redshift 17- 21 F5.2 GHz FpO Peak frequency in the observers frame 23- 27 F5.2 GHz FpR ? Peak frequency in the rest frame 29- 32 F4.2 --- var The greatest fractional variability index (1) 34- 36 I3 --- o_var Number of observations (2) 38- 43 F6.3 GHz Fvar Center frequency (3) 45- 48 F4.2 --- alpha0 ? Spectral index below the peak frequency (4) 50- 54 F5.2 --- alpha1 ? Spectral index above the peak frequency (4) 56- 58 A3 --- Class Classification proposed in this paper (5)
Note (1): The greatest fractional variability index of the data bins for the source Note (2): Number of observations in the data bin with the greatest fractional variability index Note (3): Center frequency of the data bin with the greatest fractional variability index Note (4): Spectral index α defined so that Flux density S∝να Note (5): Classification of the radio continuum spectrum as follows: gps = genuine GPS source c = convex v = variable f = flat s = steep f/s = flat at lower and steep at higher frequencies n = possible GPS source but not enough data for classification
Acknowledgements: I. Torniainen, ilo(at)
(End) I. Torniainen [Metsahovi Radio Obs.], Patricia Vannier [CDS] 25-Apr-2007
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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