Variability of optically selected quasars

DOI

The variability properties of a sample of ~300 optically selected quasars near the South Galactic Pole (SGP) have been studied over a baseline of 16 years using a series of twelve UK Schmidt Telescope B_J_ plates at seven epochs. In this sample there is a correlation between variability and both quasar luminosity and redshift, at greater than the 99 per cent significance level. Quasars of high luminosity show significantly less variability than those with low luminosity, the rms variation ranging from about 0.25mag at M_B_=-23 to 0.1mag at M_B_=-28. The observed trends can be explained by an intrinsic dependence of quasar variability on luminosity combined with the effects of time dilation, and have implications for quasar samples selected by variability or multicolour techniques. The change in the slope of the n(m) relation at the break can be less pronounced in variability-selected samples. Our results can be used to test models for the origin and reprocessing of the continuum emission in quasars.

Cone search capability for table J/MNRAS/268/305/tablea1 (Positions, redshifts, mean apparent Bj magnitudes and variability index for the SGP sample)

Identifier
DOI http://doi.org/10.26093/cds/vizier.72680305
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/MNRAS/268/305
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/268/305
Related Identifier http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/268/305
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/MNRAS/268/305
Provenance
Creator Hook I.M.; McMahon R.G.; Boyle B.J.; Irwin M.J.
Publisher CDS
Publication Year 1997
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Cosmology; Galactic and extragalactic Astronomy; High Energy Astrophysics; Natural Sciences; Observational Astronomy; Physics; Stellar Astronomy