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Related papers: Time Delay Lens Modelling Challenge

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We propose a Bayesian meta-analysis to infer the current expansion rate of the Universe, called the Hubble constant ($H_0$), via time delay cosmography. Inputs of the meta-analysis are estimates of two properties for each pair of…

Applications · Statistics 2024-11-14 Hyungsuk Tak , Xuheng Ding

While time-delay lenses can be an independent probe of $H_0$ the estimates are degenerate with the convergence of the lens near the Einstein radius. Velocity dispersions, $\sigma$, can be used to break the degeneracy, with uncertainties…

Astrophysics of Galaxies · Physics 2026-02-05 R. Forés-Toribio , C. S. Kochanek , J. A. Muñoz

Strong gravitational lensing of time variable sources such as quasars and supernovae creates observable time delays between the multiple images. Time delays can provide a powerful cosmographic probe through the "time delay distance"…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-18 Alireza Hojjati , Alex G. Kim , Eric V. Linder

One application of the Cosmological Gravitational Lensing in General Relativity is the measurement of the Hubble constant H_0 using the time delay Delta t between multiple images of lensed quasars. This method has already been applied,…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-27 Nicola Alchera , Marco Bonici , Nicola Maggiore

Time-delay cosmography can be used to infer the Hubble parameter $H_0$ by measuring the relative time delays between multiple images of gravitationally-lensed quasars. A few of such systems have already been used to measure $H_0$: their…

Instrumentation and Methods for Astrophysics · Physics 2022-08-03 L. Biggio , A. Domi , S. Tosi , G. Vernardos , D. Ricci , L. Paganin , G. Bracco

Measured time delays between the images of a gravitationally lensed source can lead to a determination of the Hubble constant ($H_o$), but only if the lensing mass distribution is well understood. The inability to sufficiently constrain…

Astrophysics · Physics 2007-05-23 D. Rusin

The determination of the Hubble parameter H_0 is probably one of the most important applications of quasar lensing. The method, based on the measurement of the so-called ``time-delay'' between the lensed images of distant sources, e.g.,…

Astrophysics · Physics 2007-05-23 F. Courbin

The time delays between point-like images in gravitational lens systems can be used to measure cosmological parameters. The number of lenses with measured time delays is growing rapidly; the upcoming \emph{Large Synoptic Survey Telescope}…

Instrumentation and Methods for Astrophysics · Physics 2015-02-05 Gregory Dobler , Christopher Fassnacht , Tommaso Treu , Phillip J. Marshall , Kai Liao , Alireza Hojjati , Eric Linder , Nicholas Rumbaugh

The potential of gravitational lenses for providing direct, physical measurements of the Hubble constant, free from systematic errors associated with the traditional distance ladder, has long been recognized. However, it is only recently…

Astrophysics · Physics 2007-05-23 Roger D. Blandford , Tomislav Kundic

Strongly gravitational lensed quasars can be used to measure the so-called time-delay distance $D_{\Delta t}$, and thus the Hubble constant $H_0$ and other cosmological parameters. Stellar kinematics of the deflector galaxy play an…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-17 Anowar J. Shajib , Tommaso Treu , Adriano Agnello

One of the main objectives of the Cosmic Lens All-Sky Survey (CLASS) collaboration has been to find gravitational lens (GL) systems at radio wavelengths that are suitable for the determination of time delays between image pairs. The survey…

Astrophysics · Physics 2009-11-06 L. V. E. Koopmans , the CLASS collaboration

We investigate the use of approximate Bayesian neural networks (BNNs) in modeling hundreds of time-delay gravitational lenses for Hubble constant ($H_0$) determination. Our BNN was trained on synthetic HST-quality images of strongly lensed…

Instrumentation and Methods for Astrophysics · Physics 2021-04-13 Ji Won Park , Sebastian Wagner-Carena , Simon Birrer , Philip J. Marshall , Joshua Yao-Yu Lin , Aaron Roodman

We present a self-consistent and versatile forward modelling software package that can produce time series and pixel-level simulations of time-varying strongly lensed systems. The time dimension, which needs to take into account different…

Instrumentation and Methods for Astrophysics · Physics 2022-02-16 Georgios Vernardos

We present a determination of the Hubble constant from the joint, free-form analysis of 8 strongly, quadruply lensing systems. In the concordance cosmology, we find $H_0 = 71.8^{+3.9}_{-3.3}\,\mathrm{km}\,\mathrm{s}^{-1}\,\mathrm{Mpc}^{-1}$…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-22 Philipp Denzel , Jonathan P. Coles , Prasenjit Saha , Liliya L. R. Williams

Gravitational time delays offer unique, independent measurements of the Hubble constant, $H_0$. Precise measurements of $H_0$ stand as one of the most pressing challenges in modern cosmology, and to do so with time delays requires precise…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-19 D. M. Williams , T. Treu , S. Birrer , A. J. Shajib , K. C. Wong , T. Morishita , T. Schmidt , M. Stiavelli

Observed time delays between images of a lensed QSO lead to the determination of the Hubble constant by Refsdal's method, provided the mass distribution in the lensing galaxy is reasonably well known. Since the two or four QSO images…

Astrophysics · Physics 2009-10-31 Liliya L. R. Williams , Prasenjit Saha

We study gravitational lens time delays for a general family of lensing potentials, which includes the popular singular isothermal elliptical potential and singular isothermal elliptical density distribution but allows general angular…

Astrophysics · Physics 2016-08-30 H. J. Witt , S. Mao , C. R. Keeton

The observable time delays between the multiple images of strong lensing systems with time variable sources can provide us with some valuable information to probe the expansion history of the Universe. Estimation of these time delays can be…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Amir Aghamousa , Arman Shafieloo

Present day estimates of the Hubble constant based on Cepheids and on the cosmic microwave background radiation are uncertain by roughly 10% (on the conservative assumption that the universe may not be PERFECTLY flat). Gravitational lens…

Astrophysics · Physics 2009-11-10 Paul L. Schechter