ar X iv : a st ro - p h / 99 05 29 3 v 1 2 2 M ay 1 99 9 Finding Gravitational Lenses With X - rays
نویسندگان
چکیده
There are ∼ 1, 0.1 and 0.01 gravitationally lensed X-ray sources per square degree with soft X-ray fluxes exceeding 10 −15 , 10 −14 and 10 −13 ergs s −1 cm −2 respectively. These sources will be detected serendipitously with the Chandra X-ray Observatory at a rate of 1–3 lenses per year of high resolution imaging. The low detection rate is due to the small area over which the HRC and ACIS cameras have the < 1. ′′ 5 FWHM resolution necessary to find gravitational lenses produced by galaxies. Deep images of rich clusters at intermediate redshifts should yield one wide separation (∆θ > ∼ 5. ′′ 0) multiply-imaged background X-ray source for every ∼ 10, 30 and 300 clusters imaged to the same flux limits.
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