Article (Scientific journals)
Polarization properties of a sample of broad absorption line and gravitationally lensed quasars
Hutsemekers, Damien; Lamy, H.; Remy, M.
1998In Astronomy and Astrophysics, 340, p. 371-380
Peer Reviewed verified by ORBi
 

Files


Full Text
1998A+A...340..371H.pdf
Publisher postprint (148.28 kB)
Download

The authors thank EDP Sciences and NASA ADS for their deposit authorization


All documents in ORBi are protected by a user license.

Send to



Details



Keywords :
POLARIZATION; GALAXIES: QUASARS: ABSORPTION LINES; GALAXIES: QUASARS: GENERAL; COSMOLOGY: GRAVITATIONAL LENSING
Abstract :
[en] New broad-band linear polarization measurements have been obtained for a sample of 42 optically selected QSOs including 29 broad absorption line (BAL) QSOs. The polarization properties of different sub-classes have been compared, and possible correlations with various spectral indices searched for. The main results of our study are: (1) Nearly all highly polarized QSOs of our sample belong to the sub-class of BAL QSOs with low-ionization absorption features (LIBAL QSOs). (2) The range of polarization is significantly larger for LIBAL QSOs than for high-ionization (HI) BAL QSOs and non-BAL QSOs. (3) There is some indication that HIBAL QSOs as a class may be more polarized than non-BAL QSOs and therefore intermediate between LIBAL and non-BAL QSOs, but the statistics are not compelling from the sample surveyed thus far. (4) For LIBAL QSOs, the continuum polarization appears significantly correlated with the line profile detachment index, in the sense that LIBAL QSOs with P Cygni-type profiles are more polarized. No correlation was found with the strength of the low- or the high-ionization absorption features, nor with the strength or the width of the emission lines. These results are consistent with a scenario in which LIBAL QSOs constitute a different class of radio-quiet QSOs with more absorbing material and more dust. Higher maximum polarization can therefore be reached, while the actually measured polarization depends on the geometry and orientation of the system as do the line profiles. The observed correlation is interpreted within the framework of recent ``wind-from-disk'' models. Tables~2 and 3 are also available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html}\fnmsep\thanks{Based on observations collected at the European Southern Observatory (ESO, La Silla)
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Hutsemekers, Damien ;  Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Astroph. extragalactique et observations spatiales (AEOS)
Lamy, H.;  Institut d'Astrophysique, Universitede Liege, 5 av. de Cointe, B-4000 Liege, Belgium
Remy, M.
Language :
English
Title :
Polarization properties of a sample of broad absorption line and gravitationally lensed quasars
Publication date :
01 December 1998
Journal title :
Astronomy and Astrophysics
ISSN :
0004-6361
eISSN :
1432-0746
Publisher :
EDP Sciences, Les Ulis, France
Volume :
340
Pages :
371-380
Peer reviewed :
Peer Reviewed verified by ORBi
Available on ORBi :
since 10 March 2010

Statistics


Number of views
55 (1 by ULiège)
Number of downloads
82 (1 by ULiège)

Scopus citations®
 
40
Scopus citations®
without self-citations
23

Bibliography


Similar publications



Contact ORBi