VDES J2325-5229 a z=2.7 gravitationally lensed quasar discovered using morphology independent supervised machine learning

Abstract

We present the discovery and preliminary characterization of a gravitationally lensed quasar with a source redshift $z_s=2.74$ and image separation of $2.9"$ lensed by a foreground $z_l=0.40$ elliptical galaxy. Since the images of gravitationally lensed quasars are the superposition of multiple point sources and a foreground lensing galaxy, we have developed a morphology independent multi-wavelength approach to the photometric selection of lensed quasar candidates based on Gaussian Mixture Models (GMM) supervised machine learning. Using this technique and $gi$ multicolour photometric observations from the Dark Energy Survey (DES), near IR $JK$ photometry from the VISTA Hemisphere Survey (VHS) and WISE mid IR photometry, we have identified a candidate system with two catalogue components with $i_{AB}=18.61$ and $i_{AB}=20.44$ comprised of an elliptical galaxy and two blue point sources. Spectroscopic follow-up with NTT and the use of an archival AAT spectrum show that the point sources can be identified as a lensed quasar with an emission line redshift of $z=2.739\pm 0.003$ and a foreground early type galaxy with $z=0.400\pm 0.002$. We model the system as a single isothermal ellipsoid and find the Einstein radius ${\theta }_E\sim 1.47"$, enclosed mass $M_{enc}\sim 4\times 10^{11}$M${}_{\odot }$ and a time delay of $\sim$52 days. The relatively wide separation, month scale time delay duration and high redshift make this an ideal system for constraining the expansion rate beyond a redshift of 1.

arXiv comment11 pages, 7 figures, 7 tables, MNRAS accepted

References in corpus (57)

• Scikit-learn: Machine Learning in Python
• Astropy: A Community Python Package for Astronomy
• The Wide-field Infrared Survey Explorer (WISE): Mission Description and Initial On-orbit Performance
• The Seventh Data Release of the Sloan Digital Sky Survey
• Accurate photometric redshifts for the CFHT Legacy Survey calibrated using the VIMOS VLT Deep Survey
• The Dark Energy Camera
• The Dark Energy Survey: more than dark energy - an overview
• Spectroscopic Target Selection in the Sloan Digital Sky Survey: The Quasar Sample
• Measuring and Modelling the Redshift Evolution of Clustering: the Hubble Deep Field North
• Mid-Infrared Selection of AGN with the Wide-Field Infrared Survey Explorer. I. Characterizing WISE-Selected AGN in COSMOS
• Eight New Milky Way Companions Discovered in First-Year Dark Energy Survey Data
• The Sloan Lens ACS Survey. X. Stellar, Dynamical, and Total Mass Correlations of Massive Early-type Galaxies
• Evidence for substructure in lens galaxies?
• H0LiCOW V. New COSMOGRAIL time delays of HE0435-1223: $H_0$ to 3.8% precision from strong lensing in a flat $\Lambda$CDM model
• Dissecting the Gravitational Lens B1608+656. II. Precision Measurements of the Hubble Constant, Spatial Curvature, and the Dark Energy Equation of State
• Gravitationally lensed quasars and supernovae in future wide-field optical imaging surveys
• Mid-Infrared Selection of Active Galactic Nuclei with the Wide-Field Infrared Survey Explorer. II. Properties of WISE-Selected Active Galactic Nuclei in the NDWFS Boötes Field
• Probing the Coevolution of Supermassive Black Holes and Galaxies Using Gravitationally Lensed Quasar Hosts
• The Cosmic Lens All-Sky Survey: I. Source selection and observations
• Gravitational detection of a low-mass dark satellite at cosmological distance
• Two accurate time-delay distances from strong lensing: Implications for cosmology
• The Quasar Accretion Disk Size -- Black Hole Mass Relation
• The Quasar Accretion Disk Size - Black Hole Mass Relation
• PESSTO : survey description and products from the first data release by the Public ESO Spectroscopic Survey of Transient Objects
• The Mass Distribution of SDSS J1004+4112 Revisited
• The Cosmic Lens All-Sky Survey:II. Gravitational lens candidate selection and follow-up
• A Description of Quasar Variability Measured Using Repeated SDSS and POSS Imaging
• Introduction to astroML: Machine Learning for Astrophysics
• The XXL Survey: I. Scientific motivations - XMM-Newton observing plan - Follow-up observations and simulation programme
• The Optical Properties of Gravitational Lens Galaxies as a Probe of Galaxy Structure and Evolution
• The 2dF QSO Redshift Survey - V. The 10k catalogue
• Tests for Substructure in Gravitational Lenses
• The Sloan Digital Sky Survey Quasar Lens Search. I. Candidate Selection Algorithm
• The Sloan Digital Sky Survey Quasar Lens Search. V. Final Catalog from the Seventh Data Release
• The Spatial Structure of An Accretion Disk
• The Evolution of a Mass-Selected Sample of Early-Type Field Galaxies
• The Importance of Einstein Rings
• Detection of substructure with adaptive optics integral field spectroscopy of the gravitational lens B1422+231
• OzDES multi-fibre spectroscopy for the Dark Energy Survey: first-year operation and results
• The Sloan Digital Sky Survey Quasar Lens Search. II. Statistical Lens Sample from the Third Data Release
• The Sloan Digital Sky Survey Quasar Lens Search. III. Constraints on Dark Energy from the Third Data Release Quasar Lens Catalog
• The Dark Energy Survey Data Processing and Calibration System
• Bayesian High-Redshift Quasar Classification from Optical and Mid-IR Photometry
• Quasar Probabilities and Redshifts from WISE mid-IR through GALEX UV Photometry
• SDSS J0903+5028: A New Gravitational Lens
• Multi wavelength study of the gravitational lens system RXS J1131-1231: II Lens model and source reconstruction
• The Sloan Digital Sky Survey Quasar Lens Search. IV. Statistical Lens Sample from the Fifth Data Release
• Discovery of two gravitationally lensed quasars in the Dark Energy Survey
• SDSS J115517.35+634622.0: A Newly Discovered Gravitationally Lensed Quasar
• A Simple Method To Find All Lensed Quasars
• A Compact Early-type Galaxy at z = 0.6 Under a Magnifying Lens: Evidence For Inside-out Growth
• A Rapidly Spinning Black Hole Powers the Einstein Cross
• The XXL survey XIV. AAOmega redshifts for the southern XXL field
• SDSS J094604.90+183541.8: A Gravitationally Lensed Quasar at z=4.8
• ULAS J234311.93-005034.0: A gravitational lens system selected from UKIDSS and SDSS
• Resolving the Clumpy Structure of the Outflow Winds in the Gravitationally Lensed Quasar SDSS J1029+2623
• Spectroscopy along Multiple, Lensed Sightlines through Outflowing Winds in the Quasar SDSS J1029+2623

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• Lenstronomy: multi-purpose gravitational lens modelling software package
• A SHARP view of H0LiCOW: $H_0$ from three time-delay gravitational lens systems with adaptive optics imaging
• STRIDES: a 3.9 per cent measurement of the Hubble constant from the strong lens system DES J0408-5354
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• Catalogues of Active Galactic Nuclei From Gaia and unWISE Data
• STRIDES: Automated uniform models for 30 quadruply imaged quasars
• The STRong lensing Insights into the Dark Energy Survey (STRIDES) 2016 follow-up campaign. I. Overview and classification of candidates selected by two techniques
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• The STRong lensing Insights into the Dark Energy Survey (STRIDES) 2017/2018 follow-up campaign: Discovery of 10 lensed quasars and 10 quasar pairs
• TDCOSMO II: 6 new time delays in lensed quasars from high-cadence monitoring at the MPIA 2.2m telescope
• Gravitationally Lensed Quasars in Gaia: I. Resolving Small-Separation Lenses
• Survey of Gravitationally-lensed Objects in HSC Imaging (SuGOHI). IV. Lensed quasar search in the HSC survey
• First lensed quasar systems from the VST-ATLAS survey: one quad, two doubles and two pairs of lensless twins
• Deep Learning for Strong Lensing Search: Tests of the Convolutional Neural Networks and New Candidates from KiDS DR3
• Gaia GraL: Gaia DR2 Gravitational Lens Systems. VI. Spectroscopic Confirmation and Modeling of Quadruply-Imaged Lensed Quasars
• HOLISMOKES -- IV. Efficient mass modeling of strong lenses through deep learning
• H0LiCOW VII. Cosmic evolution of the correlation between black hole mass and host galaxy luminosity
• Discovery of the Lensed Quasar System DES J0408-5354
• Support Vector Machine classification of strong gravitational lenses
• Constraining the microlensing effect on time delays with new time-delay prediction model in $H_0$ measurements
• The Discovery of a Five-Image Lensed Quasar at z = 3.34 using PanSTARRS1 and Gaia
• Toward an internally consistent astronomical distance scale
• The Completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: A Catalogue of Strong Galaxy-Galaxy Lens Candidates
• A Search for Gravitationally Lensed Quasars and Quasar Pairs in Pan-STARRS1: Spectroscopy and Sources of Shear in the Diamond 2M1134$-$2103
• The STRong lensing Insights into the Dark Energy Survey (STRIDES) 2016 follow-up campaign. II. New quasar lenses from double component fitting
• Models of the strongly lensed quasar DES J0408-5354
• Quasar Lenses in the South: searches over the DES public footprint
• Discovery and first models of the quadruply lensed quasar SDSS J1433+6007
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• Quasar Lenses and Galactic Streams: Outlier Selection and GAIA Multiplet Detection
• Testing the Evolution of the Correlations between Supermassive Black Holes and their Host Galaxies using Eight Strongly Lensed Quasars
• Machine Learning Based Real Bogus System for HSC-SSP Moving Object Detecting Pipeline
• Population mixtures and searches of lensed and extended quasars across photometric surveys
• Eigengalaxies: describing galaxy morphology using principal components in image space
• A Gravitationally Lensed Quasar Discovered in OGLE
• Auto-identification of unphysical source reconstructions in strong gravitational lens modelling
• HOLISMOKES -- IX. Neural network inference of strong-lens parameters and uncertainties from ground-based images
• The DES Bright Arcs Survey: Candidate Strongly Lensed Galaxy Systems from the Dark Energy Survey 5,000 Sq. Deg. Footprint
• Deep Learning Assessment of galaxy morphology in S-PLUS DataRelease 1
• Lensed quasar search via time variability with the HSC transient survey
• Detection of Strongly Lensed Arcs in Galaxy Clusters with Transformers
• Gaia GraL II - Gaia DR2 Gravitational Lens Systems: The Known Multiply Imaged Quasars
• Observation and Confirmation of Nine Strong Lensing Systems in Dark Energy Survey Year 1 Data
• TDCOSMO XVII. New time delays in 22 lensed quasars from optical monitoring with the ESO-VST 2.6m and MPG 2.2m telescopes
• Machine learning technique for morphological classification of galaxies from the SDSS. III. Image-based inference of detailed features
• Gaia GraL: Gaia DR2 Gravitational Lens Systems. VII. XMM-Newton Observations of Lensed Quasars
• Quasi-Stellar Objects acting as potential Strong Gravitational Lenses in the SDSS-III BOSS survey
• Strongly lensed candidates from the HSC transient survey
• How the spectral energy distribution and galaxy morphology constrain each other, with application to morphological selection using galaxy colours
• Model selection using time-delay lenses
• New Dynamical Measurements from a Lensed Quasar Sample: Joint Analysis Constrains the Mass Profile Evolution of Lens Galaxies