Open AccessShort‐term optical variability of high‐redshift quasi‐stellar objects
Author(s) -
Bachev R.,
Strigachev A.,
Semkov E.
Publication year - 2005
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2005.08708.x
Subject(s) - physics , quasar , astrophysics , redshift , active galactic nucleus , astronomy , luminosity , ultraviolet , accretion (finance) , quiet , relativistic beaming , wavelength , term (time) , accretion disc , galaxy , optics
In this paper we present the results of a search for short‐term variability in the optical band of selected high‐luminosity, high‐redshift radio‐quiet quasars. Each quasar has been monitored typically for 2–4 h with a time resolution of 2–5 min and a photometric accuracy of about 0.01–0.02 mag. As a result of the significant redshift ( z > 2) , the covered wavelength range falls into the ultraviolet region (typically 1500–2500 Å). We have found no statistical evidence for any continuum variations larger than 0.01–0.02 mag for any of the monitored objects. Our results suggest that the presence of a short‐term variability in radio‐quiet quasars is unlikely even in the ultraviolet region, contrary to reports by other authors. This conclusion holds true at least for high‐luminosity (large black hole mass and accretion rate?) objects. The results are consistent with the idea that significant short‐term (less than 1 h) variations in active galactic nuclei, where observed, should be attributed primarily to processes in a relativistic jet.