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arXiv · 1911.02587

Survey of Gravitationally-lensed Objects in HSC Imaging (SuGOHI). IV. Lensed quasar search in the HSC survey

James H. H. Chan·Sherry H. Suyu·Alessandro Sonnenfeld·Anton T. Jaelani·Anupreeta More·Atsunori Yonehara·Yuriko Kubota·Jean Coupon·Chien-Hsiu Lee·Masamune Oguri·Cristian E. Rusu·Kenneth C. Wong
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Abstract

Strong gravitationally lensed quasars provide powerful means to study galaxy evolution and cosmology. We use Chitah to hunt for new lens systems in the Hyper Suprime$-$Cam Subaru Strategic Program (HSC SSP) S16A. We present 46 lens candidates, of which 3 are previously known. Including 2 additional lenses found by YattaLens, we obtain X-shooter spectra of 6 promising candidates for lens confirmation and redshift measurements. We report new spectroscopic redshift measurements for both the lens and source galaxies in 4 lens systems. We apply the lens modeling software Glee to model our 6 X-shooter lenses uniformly. Through our analysis of the HSC images, we find that HSCJ022622$-$042522, HSCJ115252$+$004733, and HSCJ141136$-$010216 have point-like lensed images, and that the lens light distribution is well aligned with mass distribution within 6 deg. Thanks to the X-shooter spectra, we estimate fluxes on the Baldwin- Phillips-Terlevich (BPT) diagram, and find that HSCJ022622$-$042522 has a probable quasar source, based on the upper limit of the Nii flux intensity. We also measure the FWHM of Ly$\alpha$ emission of HSCJ141136$-$010216 to be $\sim$254 km/s, showing that it is a probable Lyman-$\alpha$ emitter.

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James H. H. Chan, Sherry H. Suyu, Alessandro Sonnenfeld, Anton T. Jaelani, Anupreeta More, Atsunori Yonehara, Yuriko Kubota, Jean Coupon, Chien-Hsiu Lee, Masamune Oguri, Cristian E. Rusu, Kenneth C. Wong. 2019-11-06. Survey of Gravitationally-lensed Objects in HSC Imaging (SuGOHI). IV. Lensed quasar search in the HSC survey. https://doi.org/10.1051/0004-6361%2F201937030

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