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arXiv · astro-ph/9912068

X-ray variability in a deep, flux limited sample of QSOs

O. Almaini·A. Lawrence·T. Shanks·A. Edge·B. J. Boyle·I. Georgantopoulos·K. F. Gunn·G. C. Stewart·R. E. Griffiths
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Abstract

We present an analysis of X-ray variability in a flux limited sample of QSOs. Selected from our deep ROSAT survey, these QSOs span a wide range in redshift ($0.1 0.5$) do not show the anti-correlation with luminosity seen in local AGN. We speculate on the implications of these results for physical models of AGN and their evolution. Finally, we find evidence for X-ray variability in an object classified as a narrow emission-line galaxy, suggesting the presence of an AGN.

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O. Almaini, A. Lawrence, T. Shanks, A. Edge, B. J. Boyle, I. Georgantopoulos, K. F. Gunn, G. C. Stewart, R. E. Griffiths. 2000-04-07. X-ray variability in a deep, flux limited sample of QSOs. https://doi.org/10.1046/j.1365-8711.2000.03385.x

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