First simultaneous UBVRI photopolarimetric observations of a sample of normal quasars

Bibcode
1992A&A...261..415T
Takalo, L. O.; Kidger, M. R.; de Diego, J. A.; Sillanpaa, A.
Bibliographical reference

Astronomy and Astrophysics (ISSN 0004-6361), vol. 261, no. 2, p. 415-418.

Advertised on:
8
1992
Number of authors
4
IAC number of authors
2
Citations
12
Refereed citations
12
Description
We present what we believe to be the first truly simultaneous UBVRI photopolarimetric results for a sample of eight 'normal' quasars. In five of these quasars we have not detected any measurable polarization, this result being consistent in some cases, but not necessarily in others, with the previous white light measurements of these quasars. 3C 273 is a well known low polarization quasar but, in two other cases (PG 1008 + 133 and PG 1351 + 64), we detected small (1.5 percent) polarization. In PG 1351 + 64 this polarization shows a degree of wavelength dependence, while the position angle of the polarization of PG 1008 + 133 shows a strong wavelength dependence. Some evidence of variations in the degree of polarization are found in some of the quasars in our sample.
Type
Refereed
Quasars
Radio astronomy
Telescopes

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