Cosmological Evolution of QSOs and Radio Galaxies from Radio — Selected Samples
نویسندگان
چکیده
منابع مشابه
Intrinsic Absorption in Radio-Selected QSOs
Moderate resolution spectra have been recorded for a sample of radio-selected QSOs (z ∼ 2.5) discovered in the “Faint Images of the Radio Sky at Twenty centimeters” (FIRST) VLA survey. This work is motivated by the study of a heterogeneous set of QSO absorption line spectra that showed that as many as 36% of the absorbers normally thought to be intergalactic are correlated with physical propert...
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We present the results from the analysis of 26 extragalactic radio sources of type FRII which were observed with the VLA at 5 GHz and around the 1.4 GHz band. The sources were selected to have redshifts in the range 0.3 < z < 1.3, radio powers between 6.9×10WHz < P151MHz < 1.3×10 WHz and angular size θ ≥ 10. We found that the depolarisation and the rms variations in the rotation measure increas...
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QSOs and radio-galaxies, together with the CMB, “normal” galaxies and clusters, represent the main source of information about the origin and evolution of the Large Scale Structure. They can be used either directly, as tracers of the density peaks, or as cosmic lighthouses, probing the Universe along the line of sight with their conspicuous flow of photons. Observations of the QSO and radio-gal...
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ژورنال
عنوان ژورنال: Symposium - International Astronomical Union
سال: 1982
ISSN: 0074-1809
DOI: 10.1017/s0074180900028382