1.2k citations · 6k across the 94 of their papers we have counts for
96 papers
TDCOSMO 2026: new insights on the Hubble tension from strong lensing time delays
TDCOSMO Collaboration, Simon Birrer, Michele Cappellari +26
We discuss the measurement of the Hubble constant () in flat cold dark matter cosmology based on the blind hierarchical analysis of 11 multiply-imaged quasars (hereafter t…
TDCOSMO 2026: A 3% measurement of the Hubble constant from strong lensing and stellar kinematics
TDCOSMO Collaboration, Simon Birrer, Michele Cappellari +26
We present cosmological constraints from 11 strongly lensed quasars with measured time delays (hereafter, the TDCOSMO-2026 sample). In addition to expanding the sample, we improve…
TDCOSMO XXX: Spatially resolved kinematics of the deflectors in time-delay lens systems B1608+656 and SDSSJ1206+4332 from JWST-NIRSpec observation
Pritom Mozumdar, Shawn Knabel, Anowar J. Shajib +3
We present spatially resolved stellar kinematics of the deflector galaxies in two time-delay lens systems, B1608+656 and SDSS J1206+4332, measured from JWST NIRSpec integral field…
TDCOSMO XXIX: JWST/NIRSpec IFU Spatially Resolved Kinematics of Three Time-delay Lenses
Shawn Knabel, Pritom Mozumdar, Anowar J. Shajib +8
Spatially resolved stellar kinematics are critical to the high precision achieved by cosmological probes utilizing time delays of strongly lensed quasars. Combined with high-resolu…
TDCOSMO. XXVII. JWST-based Lens Models and H Measurement of WFI2033, HE0435, and PG1115
D. M. Williams, T. Treu, D. P. Johnson +13
Time-delay cosmography offers a one-step, distance-ladder-independent route to the Hubble-Lemaitre constant, H_0. We present new cosmography-grade lens models of three quadruply im…
Can third- and fourth-order multipoles plus radial variation of iso-density ellipses explain the observed flux ratios in B1422231? YES, and a lesson learned from a TNG100 lensing galaxy sample
Ruizhe Feng, Dandan Xu, Dominique Sluse +3
Flux ratio anomalies in multiply-imaged quasar lenses are a long-standing issue. Using a classical system B1422+231 as a case study, we investigate how typical non-clumpy perturbat…
First measurement of narrow-line flux ratios for a lensed quasar with JWST/NIRSpec IFS
Hadrien Paugnat, Tommaso Treu, Anna M. Nierenberg +3
Strong gravitational lensing is a powerful probe of dark matter (DM) structure on subgalactic scales: in particular, statistics of flux-ratio anomalies (discrepancies between mass…
JAXtronomy: A JAX port of lenstronomy
Alan Huang, Simon Birrer, Daniel Gilman +4
Gravitational lensing is a phenomenon where light bends around massive objects, resulting in distorted images seen by an observer. Studying gravitationally lensed systems provides…
TDCOSMO XXV: Measuring H0 to 6.5% precision with quasar strong lensing and maximally flexible mass-sheet dynamics
William Sheu, Tommaso Treu, Martin Millon +16
We present a blind time-delay cosmography measurement of the Hubble-Lemaître constant based on the quadruply imaged quasar SDSSJ1433+6007. Our analysis combines deep Hubble S…
Spatially Resolved Kinematics of SLACS Lens Galaxies. II: Breaking Degeneracies with Lensing and Dynamical Models
Shawn Knabel, Tommaso Treu, Michele Cappellari +4
We model the dynamical mass density profiles of 14 strong gravitational lens galaxies from the Sloan Lens ACS (SLACS) sample using spatially resolved kinematics obtained from Keck…
TDCOSMO XXVI: Uniform lens modeling of eight doubly imaged quasars
Ryan Brady, Xiang-Yu Huang, Simon Birrer +7
We present the first uniform gravitational lens modeling analysis of eight doubly imaged quasars from multi-band observations with the Hubble Space Telescope. Previous time-delay c…
SLSim: a strong lensing population simulation package
Narayan Khadka, Simon Birrer, Henry Best +45
Gravitational lensing offers unique insights into cosmology by bending light around massive objects. Strong gravitational lensing, in particular, produces magnified and often multi…
The Carousel Lens I: A Spectroscopic Survey of the Carousel Lens Field
Jackson H. O'Donnell, Demetrius Y. Williams, Tesla E. Jeltema +18
We present a spectroscopic survey of field galaxies and lensed sources in the vicinity of the strong lensing galaxy cluster known as the Carousel lens at z=0.49. Using both Gemini/…
Line-of-sight shear in SLACS strong lenses II: validation tests with an extended sample
Natalie B. Hogg, Daniel P. Johnson, Anowar J. Shajib +1
Strong gravitational lensing images are subject to shape distortions due to inhomogeneities along the line of sight. The leading order shape distortion is shear, which, if measurab…
TDCOSMO. XXIII. Measurement of the Hubble constant from the doubly lensed quasar HE1104-1805
Eric Paic, Frédéric Courbin, Christopher D. Fassnacht +18
Time-delay cosmography leverages strongly lensed quasars to measure the Universe's current expansion rate, H_0, independently from other methods. While the latest TDCOSMO results r…
The Impact of Orbital Anisotropy Assumptions in Lensing-Dynamics Modeling
Yan Liang, Dandan Xu, Anowar J. Shajib +2
We investigate potential systematic biases introduced by assumptions regarding stellar orbital anisotropy in joint lensing-dynamics modeling. Our study employs the massive early-ty…
Investigating the Dark Energy Constraint from Strongly Lensed AGN at LSST-Scale
Sydney Erickson, Martin Millon, Padmavathi Venkatraman +12
Strongly lensed Active Galactic Nuclei (AGN) with an observable time delay can be used to constrain the expansion history of the Universe through time-delay cosmography (TDC). As t…
Constraining Cosmology with Double-source-plane Strong Gravitational Lenses from the AGEL Survey
Duncan J. Bowden, Nandini Sahu, Anowar J. Shajib +17
Double-source-plane strong gravitational lenses (DSPLs), with two sources at different redshifts, are independent cosmological probes of the dark energy equation of state parameter…
The Dark Energy Camera All Data Everywhere cosmic shear project V: Constraints on cosmology and astrophysics from 270 million galaxies across 13,000 deg of the sky
D. Anbajagane, C. Chang, A. Drlica-Wagner +78
We present constraints on models of cosmology and astrophysics using cosmic shear data vectors from three datasets: the northern and southern Galactic cap of the Dark Energy Camera…
: A Python package for removing wiggle artifacts in the JWST NIRSpec integral field spectroscopy
Anowar J. Shajib
is a Python package for removing resampling noise - commonly referred to as "wiggles'' - from spaxel-level spectra in datacubes obtained from the JWST Near Infra…
An accurate measurement of the spectral resolution of the JWST Near Infrared Spectrograph
Anowar J. Shajib, Tommaso Treu, Alejandra Melo +4
The spectral resolution () of spectroscopic data is crucial information for accurate kinematic measurements. In this letter, we present a robust measurement of the…
Analyzing Line-of-sight selection biases in galaxy-scale strong lensing with external convergence and shear
Xianzhe TZ Tang, Simon Birrer, Anowar J. Shajib +3
The upcoming Vera Rubin Observatory Legacy Survey of Space and Time (LSST) will dramatically increase the number of strong gravitational lensing systems, requiring precise modeling…
TDCOSMO XXIV. First spatially resolved kinematics of the lens galaxy obtained using JWST-NIRSpec to improve time-delay cosmography
Anowar J. Shajib, Tommaso Treu, Sherry H. Suyu +15
Spatially resolved stellar kinematics has become a key ingredient in time-delay cosmography to break the mass-sheet degeneracy in the mass profile and in turn provide a precise con…
TDCOSMO 2025: Cosmological constraints from strong lensing time delays
TDCOSMO Collaboration, Simon Birrer, Elizabeth J. Buckley-Geer +30
We present cosmological constraints from 8 strongly lensed quasars (hereafter, the TDCOSMO-2025 sample). Building on previous work, our analysis incorporated new deflector stellar…