Redshift Distribution of Quasi-Stellar Objects and the Radio Source Counts

The optical polarization of radio-loud and radio-intermediate broad absorption line quasi-stellar objects

On the basis of a sample of approximately 50 broad absorption line quasi-stellar objects (BAL QSOs), we investigate possible correlations between BAL QSO radio properties and other spectral characteristics, including polarization. For this purpose new polarization data have been obtained. The main result of our statistical study is the absence of significant correlations between the radio-to-op...

Microlensing of quasi-stellar objects (QSOs)

Very close pairs of quasi-stellar objects

It is pointed out that there are now known four very close pairs of QSOs with separations < 5 arcsec and very different redshifts. Several estimates indicates that the probability that they are accidental configurations are small; a conservative estimate of the probability to have four such pairs by random projection yields 3.5 × 10−3. We conclude either that this is further evidence that QSOs ...

The ATESP radio survey III . Source counts

This paper is part of a series reporting the results of the ATESP radio survey obtained at 1.4 GHz with the Australia Telescope Compact Array. The survey consists of 16 radio mosaics with ∼ 8 ′′ × 14 ′′ resolution and uniform sensitivity (1σ noise level ∼79 µJy) over the whole area of the ESO Slice Project redshift survey (∼ 26 sq. degrees at δ ∼ −40 •). The ATESP survey has produced a catalogu...

The Distribution of Redshifts in New Samples of Quasi-stellar Objects

Two new samples of QSOs have been constructed from recent surveys to test the hypothesis that the redshift distribution of bright QSOs is periodic in log(1 + z). The first of these comprises 57 different redshifts among all known close pairs or multiple QSOs, with image separations ≤ 10, and the second consists of 39 QSOs selected through their X-ray emission and their proximity to bright compa...