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arXiv · 1805.11103

Quasar Lenses in the South: searches over the DES public footprint

Adriano Agnello·Chiara Spiniello
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Abstract

We have scanned 5000 deg$^{2}$ of Southern Sky to search for strongly lensed quasars with five methods, all source-oriented, but based on different assumptions and selection criteria. We analyse morphological searches based on Gaia multiplet detection and chromatic offsets, fibre-spectroscopic preselection, and X-ray and radio preselection. The performance and complementarity of the methods are evaluated on a common sample of known lenses in the Dark Energy Survey public DR1 footprint. We recovered in total 13 known lenses, of which 8 quadruplets. The method that found the largest number of known lenses is the one based on morphological and colour selection of objects from the WISE and Gaia-DR2 Surveys. We finally present a list of high-grade candidates from each method, to facilitate follow-up spectroscopic campaigns, including two previously unknown quadruplets: WG210014.9-445206.4 and WG021416.37-210535.3.

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Adriano Agnello, Chiara Spiniello. 2018-05-28. Quasar Lenses in the South: searches over the DES public footprint. https://doi.org/10.1093/mnras%2Fstz2200

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