First Lensed Quasar Systems from the VST-ATLAS Survey: One Quad, Two Doubles, and Two Pairs of Lensless Twins
Name
Schechter_2017_AJ_153_219.pdf
Size
1.3 MB
Format
Adobe PDF
Checksum (MD5)
a6fbfb4c23a6ec37e7e984dd474673a6
Author(s)
Chehade, B.
Metcalfe, N.
Shanks, T.
McDonald, Michael A.
Morgan, Nicholas D., 1975-
Schechter, Paul L.
Date Issued
April 2017
Journal
Astronomical Journal
Publisher
IOP Publishing
Citation
Schechter, Paul L. et al. “First Lensed Quasar Systems from the VST-ATLAS Survey: One Quad, Two Doubles, and Two Pairs of Lensless Twins.” The Astronomical Journal 153, 5 (April 2017): 219 © 2017 The American Astronomical Society
Version
Final published version
Abstract
We have analyzed images from the VST-ATLAS survey to identify candidate gravitationally lensed quasar systems in a sample of WISE sources with W1 - W2 ≥ 0.7.. Results from follow-up spectroscopy with the Baade 6.5 m telescope are presented for eight systems. One of them is a quadruply lensed quasar, and two are doubly lensed systems. Two are projected superpositions of two quasars at different redshifts. In one system, two quasars, although at the same redshift, have very different emission line profiles and constitute a physical binary. In two systems, the component spectra are consistent with the lensing hypothesis, after allowing for microlensing. However, as no lensing galaxy is detected in these two systems, we classify them as lensless twins. More extensive observations are needed to establish whether they are in fact lensed quasars or physical binaries.
MIT Department
MIT Kavli Institute for Astrophysics and Space Research
Terms of Use
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.3847/1538-3881/AA6899
