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arXiv · astro-ph/9407003

The Ensemble Variability Properties of Faint QSOs

D. Trevese·R. G. Kron·S. R. Majewski·M. A. Bershady·D. C. Koo
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Abstract

A refined sample of 64 variable objects with stellar image structure has been identified in SA 57 to $B \sim 22.5$, over a time baseline of 15 years, sampled at 11 distinct epochs. The photometric data typically have a root-mean-square error at $B = 22$ of only 0.05 mag. Thirty-five quasars in this field have already been spectroscopically confirmed, 34 of which are among the sample of variables. Of the other variables, 6 are known spectroscopically to be stars, 10 additional objects are stars based on reliable detection of proper motion, and 1 is spectroscopically a narrow-emission-line galaxy. Of the 13 remaining variables, it is argued that they are a mixture of distant halo subdwarfs and quasars with star-like colors. We compute the ensemble average structure function and autocorrelation function from the light curves in the respective quasar rest-frames, which are used to investigate the general dependences on apparent magnitude, absolute magnitude, and redshift.

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D. Trevese, R. G. Kron, S. R. Majewski, M. A. Bershady, D. C. Koo. 1994-07-01. The Ensemble Variability Properties of Faint QSOs. https://doi.org/10.1086/174661

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