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arXiv · 0708.0871

Discovery of Four Gravitationally Lensed Quasars from the Sloan Digital Sky Survey

Masamune Oguri·Naohisa Inada·Alejandro Clocchiatti·Issha Kayo·Min-Su Shin·Joseph F. Hennawi·Michael A. Strauss·Tomoki Morokuma·Donald P. Schneider·Donald G. York
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Abstract

We present the discovery of four gravitationally lensed quasars selected from the spectroscopic quasar catalog of the Sloan Digital Sky Survey. We describe imaging and spectroscopic follow-up observations that support the lensing interpretation of the following four quasars: SDSS J0832+0404 (image separation θ=1.98", source redshift z_s=1.115, lens redshift z_l=0.659); SDSS J1216+3529 (θ=1.49", z_s=2.012); SDSS J1322+1052 (θ=2.00", z_s=1.716); and SDSS J1524+4409 (θ=1.67", z_s=1.210, z_l=0.320). Each system has two lensed images. We find that the fainter image component of SDSS J0832+0404 is significantly redder than the brighter component, perhaps because of differential reddening by the lensing galaxy. The lens potential of SDSS J1216+3529 might be complicated by the presence of a secondary galaxy near the main lensing galaxy.

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Masamune Oguri, Naohisa Inada, Alejandro Clocchiatti, Issha Kayo, Min-Su Shin, Joseph F. Hennawi, Michael A. Strauss, Tomoki Morokuma, Donald P. Schneider, Donald G. York. 2007-11-25. Discovery of Four Gravitationally Lensed Quasars from the Sloan Digital Sky Survey. https://doi.org/10.1088/0004-6256%2F135%2F2%2F520

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