English

Optical Polarization of 52 Radio-Loud QSOs and BL Lac Objects

Astrophysics 2009-10-30 v1

Abstract

Polarization measurements are presented for 52 radio-loud QSOs and BL Lac objects. For 9 highly polarized (p >3%) AGN, these are the first published polarization measurements. Of these 9, 7 are highly-polarized QSOs (HPQs), one is a BL Lac object and another is a likely BL Lac object. Polarization variability is confirmed for some of these new and previously known highly-polarized AGN. While 6 of the HPQs have flat radio spectra are almost certainly blazars, PKS 1452-217 is probably a new member of the rare class of radio-loud QSOs that show high polarization by scattering, and is therefore important for testing orientation Unified Schemes. In competition for the highest redshift HPQ are the well-observed QSO PKS 0438-43 at z = 2.85, with maximum p = 4.7%, and PKS 0046-315 at z = 2.72, for which we find p = 13%.

Keywords

Cite

@article{arxiv.astro-ph/9808060,
  title  = {Optical Polarization of 52 Radio-Loud QSOs and BL Lac Objects},
  author = {Natarajan Visvanathan and Beverley J. Wills and .},
  journal= {arXiv preprint arXiv:astro-ph/9808060},
  year   = {2009}
}

Comments

6 pages. Astronomical Journal, in press