Do Quasars Lens Quasars?
نویسنده
چکیده
If the unexpectedly high frequency of quasar pairs with very different component redshifts is due to the lensing of a population of background quasars by the foreground quasar, typical lens masses must be ∼ 10M⊙ and the sum of all such quasar lenses would have to contain ∼ 0.005 times the closure density of the Universe. It then seems plausible that a very high fraction of all ∼ 10M⊙ gravitational lenses with redshifts z ∼ 1 contain quasars. Here I propose that these systems have evolved to form the present population of massive galaxies with MB ≤ −22 and M> 5× 10 M⊙. Subject headings: cosmology: gravitational lensing — galaxies: statistics, evolution, quasars
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