Quasar lenses and pairs in the VST-ATLAS and Gaia

Agnello, A.; Schechter, P.L.; Morgan, N.D.; Treu, T.; Grillo, C.; Malesani, D.; Anguita, T.; Apostolovski, Y.; Rusu, C.E.; Motta, V.; Rojas, K.; Chehade, B.; Shanks, T.

doi:10.1093/mnras/stx3226

Quasar lenses and pairs in the VST-ATLAS and Gaia

Agnello, A.; Schechter, P.L.; Morgan, N.D.; Treu, T.; Grillo, C.; Malesani, D.; Anguita, T.; Apostolovski, Y.; Rusu, C.E.; Motta, V.; Rojas, K.; Chehade, B.; Shanks, T.

Authors

A. Agnello

P.L. Schechter

N.D. Morgan

T. Treu

C. Grillo

D. Malesani

T. Anguita

Y. Apostolovski

C.E. Rusu

V. Motta

K. Rojas

B. Chehade

T. Shanks

Abstract

We report on discovery results from a quasar lens search in the ATLAS-DR3 public footprint. Spectroscopic follow-up campaigns, conducted at the 2.6 m Nordic Optical Telescope (La Palma) and 3.6 m New Technology Telescope (La Silla) in 2016, yielded seven pairs of quasars exhibiting the same lines at the same redshift and monotonic flux ratios with wavelength (hereafter NIQs, nearly identical quasar pairs). Magellan spectra of A0140−1152 (01h40m03 s. 0–11d52m19 s. 0, zs = 1.807) confirm it as a lens with deflector at zl = 0.277 and Einstein radius θE = (0.73 ± 0.02) arcsec. Follow-up imaging of the NIQ A2213−2652 (22h13m38 s. 4–26d52m27 s. 1) reveals the deflector galaxy and confirms it as a lens. We show the use of spatial resolution from the Gaia mission to select lenses and list additional systems from a WISE-Gaia-ATLAS search, yielding three additional lenses (02h35m27 s. 4–24d33m13 s. 2, 02h59m33s–23d38m01 s. 8, 01h46m32 s. 9–11d33m39 s. 0). The overall sample consists of 11 lenses/NIQs, plus three lenses known before 2016, over the ATLAS-DR3 footprint (≈3500 deg2). Finally, we discuss future prospects for objective classification of pair/NIQ/contaminant spectra.

Citation

Agnello, A., Schechter, P., Morgan, N., Treu, T., Grillo, C., Malesani, D., …Shanks, T. (2018). Quasar lenses and pairs in the VST-ATLAS and Gaia. Monthly Notices of the Royal Astronomical Society, 475(2), 2086-2096. https://doi.org/10.1093/mnras/stx3226

Journal Article Type	Article
Acceptance Date	Dec 8, 2017
Online Publication Date	Dec 13, 2017
Publication Date	Apr 1, 2018
Deposit Date	Mar 29, 2018
Publicly Available Date	Mar 29, 2018
Journal	Monthly Notices of the Royal Astronomical Society
Print ISSN	0035-8711
Electronic ISSN	1365-2966
Publisher	Royal Astronomical Society
Peer Reviewed	Peer Reviewed
Volume	475
Issue	2
Pages	2086-2096
DOI	https://doi.org/10.1093/mnras/stx3226

Files

Published Journal Article (1.4 Mb)
PDF

Copyright Statement
This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2017 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.