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Related papers: Time Delay Lens Modelling Challenge

200 papers

Strong gravitational lensing provides an independent measurement of the Hubble parameter ($H_0$). One remaining systematic is a bias from the additional mass due to a galaxy group at the lens redshift or along the sightline. We quantify…

The largest source of systematic errors in the time-delay cosmography method likely arises from the lens model mass distribution, where an inaccurate choice of model could in principle bias the value of $H_0$. A Bayesian hierarchical…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-09 Matthew R. Gomer , Dominique Sluse , Lyne Van de Vyvere , Simon Birrer , Frederic Courbin

The sample of time-delay gravitational lenses appropriate for studying the geometry of the Universe continues to grow as dedicated campaigns, such as the Dark Energy Survey, the VST ATLAS survey, and the Large Synoptic Survey Telescope,…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-01 Fulvio Melia , Jun-Jie Wei , Xue-Feng Wu

We consider the possibility that future wide-field time-domain optical imaging surveys may be able to discover gravitationally lensed quasar pairs through serendipitous measurements of their time delays. We discuss the merits such a…

Astrophysics · Physics 2009-11-10 Bart Pindor

The 0th, 1st and 2nd derivatives of a ``Fermat potential'' give the three D's of gravitational lensing: delay, deflection and distortion. Observations of these delays, deflections and distortions for doubly and quadruply imaged quasars give…

Astrophysics · Physics 2007-05-23 Paul L. Schechter

In this work, we present a homogeneous curve-shifting analysis using the difference-smoothing technique of the publicly available light curves of 24 gravitationally lensed quasars, for which time delays have been reported in the literature.…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-24 S. Rathna Kumar , C. S. Stalin , T. P. Prabhu

Isothermal models and other simple smooth models of dark matter halos of gravitational lenses often predict a dimensionless time delay $H_0\Delta t$ much too small to be comfortable with the observed time delays $\Delta t$ and the widely…

Astrophysics · Physics 2007-05-23 HongSheng Zhao , Bo Qin

The Hubble constant ($H_0$), a crucial parameter in cosmology, quantifies the expansion rate of the universe so its precise measurement is important to understand the fundamental dynamics of our evolving universe. One of the major…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-29 Narayan Khadka , Simon Birrer , Alexie Leauthaud , Holden Nix

Time-delay cosmography is a powerful technique to constrain cosmological parameters, particularly the Hubble constant ($H_{0}$). The TDCOSMO collaboration is performing an ongoing analysis of lensed quasars to constrain cosmology using this…

Challenges inherent to high-resolution and high signal-to-noise data as well as model degeneracies can cause systematic biases in analyses of strong lens systems. In the past decade, the number of lens modeling methods has significantly…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-10 A. Galan , G. Vernardos , Q. Minor , D. Sluse , L. Van de Vyvere , M. Gomer

Gravitational lensing offers a competitive method to measure $H_0$ with the goal of 1% precision. A major obstacle comes in the form of lensing degeneracies, such as the mass sheet degeneracy (MSD), which make it possible for a family of…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-01 Matthew R. Gomer , Liliya L. R. Williams

Under the assumption of a flat Lambda-CDM cosmology, recent data from the Planck satellite point toward a Hubble constant that is in tension with that measured by gravitational lens time delays and by the local distance ladder. Prosaically,…

The precision reached by current and forthcoming strong-lensing observations requires to accurately model various perturbations to the main deflector. Hitherto, theoretical models have been developed to account for either cosmological…

General Relativity and Quantum Cosmology · Physics 2022-05-10 Pierre Fleury , Julien Larena , Jean-Philippe Uzan

We present a blind time-delay cosmographic analysis for the lens system DES J0408$-$5354. This system is extraordinary for the presence of two sets of multiple images at different redshifts, which provide the opportunity to obtain more…

(abridged) Gravitationally lensed quasars can be used as powerful cosmological and astrophysical probes. We can (i) infer the Hubble constant based on the time-delay technique, (ii) unveil substructures along the l.o.s. toward distant…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-05 D. Sluse , V. Chantry , P. Magain , F. Courbin , G. Meylan

We make a number of comments regarding modeling degeneracies in strong lensing measurements of the Hubble parameter $H_0$. The first point concerns the impact of weak lensing associated with different segments of the line of sight. We show…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-25 Luca Teodori , Kfir Blum , Emanuele Castorina , Marko Simonović , Yotam Soreq

LISA might detect gravitational waves from mergers of massive black hole binaries strongly lensed by intervening galaxies (Sereno et al. 2010). The detection of multiple gravitational lensing events would provide a new tool for cosmography.…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 M. Sereno , Ph. Jetzer , A. Sesana , M. Volonteri

We present a novel approach to estimate the time delay between light curves of multiple images in a gravitationally lensed system, based on Kernel methods in the context of machine learning. We perform various experiments with artificially…

Astrophysics · Physics 2009-11-11 Juan C. Cuevas-Tello , Peter Tino , Somak Raychaudhury

The central ambition of the modern time delay cosmography consists in determining the Hubble constant $H_0$ with a competitive precision. However, the tension with $H_0$ obtained from the Planck satellite for a spatially-flat $\Lambda$CDM…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-03 Olivier Wertz , Bastian Orthen , Peter Schneider

Strong gravitational lensing effect is a powerful tool to probe cosmological models and gravity theories. Recently, the time-delay cosmography from strong lensing and the stellar kinematics of the deflector, which encode the Hubble constant…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-14 Ran Gao , Zhengxiang Li , He Gao