Aligned radio polarizations of quasars

We have used the very large Jodrell Bank VLA Astrometric Survey/Cosmic Lens All-Sky Survey 8.4-GHz surveys of flat-spectrum radio sources to test the hypothesis that there is a systematic alignment of polarization position angle vectors on cosmological scales of the type claimed by Hutsemekers et al. (2005, Cat. <J/A+A/441/915>). The polarization position angles of 4290 sources with polarized flux density 1mJy have been examined.

They do not reveal large-scale alignments either as a whole or when split in half into high-redshift (z>=1.24) and low-redshift subsamples. Nor do the radio sources which lie in the specific areas covered by Hutsemekers et al. (<J/A+A/441/915>) show any significant effect. We have also looked at the position angles of parsec-scale jets derived from very long baseline interferometry observations and again find no evidence for systematic alignments.