Effect Of Galaxy Evolution On The Statistical Properties Of Gravitational Lenses
نویسنده
چکیده
In this paper we study how the statistical properties of gravitational lenses are modified when galaxy evolution is taken into account. We consider models of the universe in which the cosmological term Λ decreases with time or remains constant, both with and without the evolution of galaxies. We show that the probability of a beam encountering a lens event (lens optical depth) for a source at zs (normalized by the lens efficiency parameter F ∗) in a flat model of universe decreases further if evolution of galaxy is taken into account. Other statistical properties of gravitational lenses are similarly studied in different models of the universe. Subject headings: cosmology: theory – gravitational lensing – galaxy: evolution
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