J1721+8842: The first Einstein zig-zag lens

Abstract

We report the discovery of the first example of an Einstein zig-zag lens, an extremely rare lensing configuration. In this system, J1721+8842, six images of the same background quasar are formed by two intervening galaxies, one at redshift $z_1=0.184$ and a second one at $z_2=1.885$. Two out of the six multiple images are deflected in opposite directions as they pass the first lens galaxy on one side, and the second on the other side -- the optical paths forming zig-zags between the two deflectors. In this letter, we demonstrate that J1721+8842, previously thought to be a lensed dual quasar, is in fact a compound lens with the more distant lens galaxy also being distorted as an arc by the foreground galaxy. Evidence supporting this unusual lensing scenario includes: 1- identical light curves in all six lensed quasar images obtained from two years of monitoring at the Nordic Optical Telescope; 2- detection of the additional deflector at redshift $z_2=1.885$ in JWST/NIRSpec IFU data; and 3- a multiple-plane lens model reproducing the observed image positions. This unique configuration offers the opportunity to combine two major lensing cosmological probes: time-delay cosmography and dual source-plane lensing since J1721+8842 features multiple lensed sources forming two distinct Einstein radii of different sizes, one of which being a variable quasar. We expect tight constraints on the Hubble constant and the equation of state of dark energy by combining these two probes on the same system. The $z_2=1.885$ deflector, a quiescent galaxy, is also the highest-redshift strong galaxy-scale lens with a spectroscopic redshift measurement.

6 pages, 3 figures

References in corpus (46)

• H0LiCOW XIII. A 2.4% measurement of $H_0$ from lensed quasars: $5.3\sigma$ tension between early and late-Universe probes
• The Near-Infrared Spectrograph (NIRSpec) on the James Webb Space Telescope I. Overview of the instrument and its capabilities
• TDCOSMO IV: Hierarchical time-delay cosmography -- joint inference of the Hubble constant and galaxy density profiles
• 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
• Mass-sheet degeneracy, power-law models and external convergence: Impact on the determination of the Hubble constant from gravitational lensing
• STRIDES: a 3.9 per cent measurement of the Hubble constant from the strong lens system DES J0408-5354
• TDCOSMO. I. An exploration of systematic uncertainties in the inference of $H_0$ from time-delay cosmography
• The Sloan Lens ACS Survey. VI: Discovery and analysis of a double Einstein ring
• lenstronomy II: A gravitational lensing software ecosystem
• Cosmological Constraints from Strong Gravitational Lensing in Galaxy Clusters
• Cosmological Constraints from the double source plane lens SDSSJ0946+1006
• Constraints on the Hubble constant from Supernova Refsdal's reappearance
• Dark matter halos of massive elliptical galaxies at $z\sim 0.2$ are well described by the Navarro-Frenk-White profile
• H0LiCOW III. Quantifying the effect of mass along the line of sight to the gravitational lens HE 0435-1223 through weighted galaxy counts
• Gravitationally Lensed Quasars in Gaia: II. Discovery of 24 Lensed Quasars
• TDCOSMO. XII. Improved Hubble constant measurement from lensing time delays using spatially resolved stellar kinematics of the lens galaxy
• The Sloan Digital Sky Survey Quasar Lens Search. VI. Constraints on Dark Energy and the Evolution of Massive Galaxies
• Gravitationally lensed quasars in Gaia -- IV. 150 new lenses, quasar pairs, and projected quasars
• Gravitational lenses as cosmic rulers: density of dark matter and dark energy from time delays and velocity dispersions
• STRIDES: Automated uniform models for 30 quadruply imaged quasars
• Could quasar lensing time delays hint to a core component in halos, instead of H0 tension?
• Constraining the dark energy equation of state with double source plane strong lenses
• H0LiCOW VIII. A weak lensing measurement of the external convergence in the field of the lensed quasar HE0435$-$1223
• Cosmography with Supernova Refsdal through time-delay cluster lensing: independent measurements of the Hubble constant and geometry of the Universe
• A glance at the host galaxy of high-redshift quasars using strong damped Lyman-alpha systems as coronagraphs
• Galaxy cluster strong lensing cosmography: cosmological constraints from a sample of regular galaxy clusters
• The inner dark matter distribution of the Cosmic Horseshoe (J1148+1930) with gravitational lensing and dynamics
• The mass profile of early-type galaxies in overdense environments: the case of the double source plane gravitational lens SL2SJ02176-0513
• Can one determine cosmological parameters from multi-plane strong lens systems?
• TDCOSMO X. Automated Modeling of 9 Strongly Lensed Quasars and Comparison Between Lens Modeling Software
• Discovery of a Strong Lensing Galaxy Embedded in a Cluster at z = 1.62
• A Spectroscopically Confirmed Double Source Plane Lens System in the Hyper Suprime-Cam Subaru Strategic Program
• Compound lensing: Einstein Zig-Zags and high multiplicity lensed images
• H0LiCOW XI. A weak lensing measurement of the external convergence in the field of the lensed quasar B1608+656 using HST and Subaru deep imaging
• J1721$+$8842: a gravitationally lensed binary quasar with a proximate damped Lyman-$\alpha$ absorber
• Generalized multi-plane gravitational lensing: time delays, recursive lens equation, and the mass-sheet transformation
• Doubling Strong Lensing as a Cosmological Probe
• The COSMOS-Web ring: in-depth characterization of an Einstein ring lensing system at z~2
• TDCOSMO XIV: Practical Techniques for Estimating External Convergence of Strong Gravitational Lens Systems and Applications to the SDSS J0924+0219 System
• Testing Cosmology with Double Source Lensing
• Reconstructing the extended structure of multiple sources strongly lensed by the ultra-massive elliptical galaxy SDSS J0100+1818
• On Multiple Einstein Rings
• PS J1721+8842: A gravitationally lensed dual AGN system at redshift 2.37 with two radio components
• lightcurver: A Python Pipeline for Precise Photometry of Multiple-Epoch Wide-Field Images
• Cosmography from accurate mass modeling of the lens group SDSS J0100+1818: five sources at three different redshifts

Cited by in corpus (3)

• An extended and extremely thin gravitational arc from a lensed compact symmetric object at redshift 2.059
• Line-of-sight effects on double source plane lenses
• Time to Sparkler. Accurate ages of lensed globular clusters at $z=1.4$ with JWST photometry