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Title: A Mock Catalog of Gravitationally-lensed Quasars for the LSST Survey
Abstract We present a mock catalog of gravitationally-lensed quasars atzqso< 7.5 with simulated images for the Rubin Observatory Legacy Survey of Space and Time (LSST). We adopt recent measurements of quasar-luminosity functions to model the quasar population, and use the CosmoDC2 mock galaxy catalog to model the deflector galaxies, which successfully reproduces the observed galaxy-velocity dispersion functions up tozd∼ 1.5. The mock catalog is highly complete for lensed quasars with Einstein radiusθE> 0.″07 and quasar absolute magnitudeMi< − 20. We estimate that there are ∼103lensed quasars discoverable in current imaging surveys, and LSST will increase this number to ∼ 2.4 × 103. Most of the lensed quasars have image separation Δθ> 0.″5, which will at least be marginally resolved in LSST images with seeing of ∼0.″7. There will be ∼200 quadruply-lensed quasars discoverable in the LSST. The fraction of quad lenses among all discoverable lensed quasars is about ∼10%–15%, and this fraction decreases with survey depth. This mock catalog shows a large diversity in the observational features of lensed quasars, in terms of lensing separation and quasar-to-deflector flux ratio. We discuss possible strategies for a complete search of lensed quasars in the LSST era.  more » « less
Award ID(s):
1908284
PAR ID:
10363079
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astronomical Journal
Volume:
163
Issue:
3
ISSN:
0004-6256
Format(s):
Medium: X Size: Article No. 139
Size(s):
Article No. 139
Sponsoring Org:
National Science Foundation
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