ar X iv : a st ro - p h / 00 08 12 4 v 1 8 A ug 2 00 0 Multi - Frequency Analysis of the New Wide - Separation Gravitational Lens
نویسندگان
چکیده
We report the discovery of a new two-image gravitational lens candidate. The system RXJ0921+4529 contains two zs = 1.66 quasars separated by 6. 93 with an H band magnitude difference of ∆m = 1.39. The HST NIC2 H band images reveal an H=18.2 spiral galaxy between the quasar images, which is probably a member of a zl = 0.32 X-ray cluster centered on the field. We detect an extended source near the fainter quasar image but not in the brighter image. If this extended source is the host galaxy of the fainter quasar, then the system is a binary quasar rather than a gravitational lens. VLA observations at 3.6 cm reveal emission from the lens galaxy at the flux level of 1mJy and a marginal detection of the brighter quasar. Subject headings: cosmology: gravitational lensing — quasars: individual (RXJ0921+4528)
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