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Faint galaxies around quasars at z=1 and gravitational lensing of distant objects

J. W. Fried
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Abstract

Very deep imaging data of three optically luminous radio-loud quasars with redshifts between z=0.9 and z=1.36 are presented. The data are complete for galaxies down to R=26. There is no evidence for excess numbers of galaxies around the quasars; foreground galaxy clusters are excluded by the data as well as clusters with richness classes greater than 1 associated with the quasars. We find clear evidence for gravitational lensing for two quasars. It is further shown that due to the high surface density of galaxies all distant (z>1) objects are moderately affected by gravitational lensing; the amplification factors are estimated to be in the range 1.1-1.5.

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J. W. Fried. 1996-12-03. Faint galaxies around quasars at z=1 and gravitational lensing of distant objects. https://arxiv.org/abs/astro-ph/9612031

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