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Weak lensing is commonly measured using shear through galaxy ellipticities, or using the effect of magnification bias on galaxy number densities. Here, we report on the first detection of weak lensing magnification with a new, independent…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Fabian Schmidt , Alexie Leauthaud , Richard Massey , Jason Rhodes , Matthew R. George , Anton M. Koekemoer , Alexis Finoguenov , Masayuki Tanaka

A new method for measuring gravitational lensing with high redshift type Ia supernovae is investigated. The method utilizes correlations between foreground galaxies and supernova brightnesses to substantially reduce possible systematic…

Astrophysics · Physics 2017-03-22 R. Benton Metcalf

We investigate how Einstein rings and magnified arcs are affected by small-mass dark-matter haloes placed along the line-of-sight to gravitational lens systems. By comparing the gravitational signature of line-of-sight haloes with that of…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-07 Giulia Despali , Simona Vegetti , Simon D. M. White , Carlo Giocoli , Frank C. van den Bosch

We explore the halo structure of four gravitational lenses with well-observed, thin Einstein rings. We find that the gravitational potentials are well described by ellipsoidal density distributions in the sense that the best-fit…

Astrophysics · Physics 2009-11-13 Jaiyul Yoo , Christopher S. Kochanek , Emilio E. Falco , Brian A. McLeod

Many strong gravitational lenses lie in complex environments, such as poor groups of galaxies, that significantly bias conclusions from lens analyses. We are undertaking a photometric survey of all known galaxy-mass strong lenses to…

Astrophysics · Physics 2010-11-11 K. A. Williams , I. Momcheva , C. R. Keeton , A. I. Zabludoff , J. Lehar

With the increase in the number of observed gravitational wave (GW) signals, detecting strongly lensed GWs by galaxies has become a real possibility. Lens galaxies also contain microlenses (e.g., stars and black holes), introducing further…

Astrophysics of Galaxies · Physics 2022-10-05 Ashish Kumar Meena , Anuj Mishra , Anupreeta More , Sukanta Bose , Jasjeet Singh Bagla

Efficient algorithms are being developed to search for strong gravitational lens systems owing to increasing large imaging surveys. Neural networks have been successfully used to discover galaxy-scale lens systems in imaging surveys such as…

Gravitational lensing has been identified as a powerful tool to address fundamental problems in astrophysics at different scales, ranging from exoplanet identification to dark energy and dark matter characterization in cosmology. Image…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-17 Andrés A. Plazas

Gravitational lensing observables, including anomalies in image positions, flux ratios, and time delays, serve as usual probes of dark matter (DM) substructure. When dark matter substructure possesses sufficient perturbations, it may lead…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-13 Wenlin Hou , Jianxiang Liu , Kai Liao

Weak shear maps of the outer regions of clusters have been successfully used to map the distribution of mass at large radii from the cluster center. The typical smoothing lengths employed thus far preclude the systematic study of the…

Astrophysics · Physics 2015-06-24 Priyamvada Natarajan , Jean-Paul Kneib

We have worked out simple analytical formulae that accurately approximate the relationship between the position of the source with respect to the lens center and the amplification of the images, hence the lens cross section, for realistic…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 A. Lapi , M. Negrello , J. Gonzalez-Nuevo , Z. -Y. Cai , G. De Zotti , L. Danese

Object segmentation and structure localization are important steps in automated image analysis pipelines for microscopy images. We present a convolution neural network (CNN) based deep learning architecture for segmentation of objects in…

Computer Vision and Pattern Recognition · Computer Science 2019-01-24 Shan E Ahmed Raza , Linda Cheung , Muhammad Shaban , Simon Graham , David Epstein , Stella Pelengaris , Michael Khan , Nasir M. Rajpoot

Dark matter structures within strong gravitational lens galaxies and along their line of sight leave a gravitational imprint on the multiple images of lensed sources. Strong gravitational lensing provides, therefore, a key test of different…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-22 S. Vegetti , S. Birrer , G. Despali , C. D. Fassnacht , D. Gilman , Y. Hezaveh , L. Perreault Levasseur , J. P. McKean , D. M. Powell , C. M. O'Riordan , G. Vernardos

Gravitational lensing refers to the deflection of light by the gravity of celestial bodies, often predominantly composed of dark matter. Seen through a gravitational lens, the images of distant galaxies appear distorted. In this paper we…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-22 Hans Georg Schaatun , Ben David Normann , Einar Leite Austnes , Simon Ingebrigtsen , Sondre Westbø Remøy , Simon Nedreberg Runde

Einstein rings are rare gem of the strong lensing phenomena. Unlike doubly or quadruply lensed systems, the ring images can be used to probe the underlying lens gravitational potential at every position angle, putting much tighter…

Astrophysics of Galaxies · Physics 2017-04-05 Chien-Hsiu Lee

Image distortion due to weak gravitational lensing is examined using a non-perturbative method of integrating the geodesic deviation and optical scalar equations along the null geodesics connecting the observer to a distant source. The…

General Relativity and Quantum Cosmology · Physics 2011-09-28 Thomas P. Kling , Louis Bianchini

We study the gravitational lensing of high-redshift sources in a LCDM universe. We have performed a series of ray-tracing experiments, and selected a subsample of cases of strong lensing (multiple images, arcs, and Einstein rings). For each…

Astrophysics · Physics 2009-11-10 Premana Premadi , Hugo Martel

We investigate strong gravitational lensing in the concordance $\Lambda$CDM cosmology by carrying out ray-tracing along past light cones through the Millennium Simulation, the largest simulation of cosmic structure formation ever carried…

Astrophysics · Physics 2007-12-03 Stefan Hilbert , Simon D. M. White , Jan Hartlap , Peter Schneider

To evaluate their performance, existing dehazing approaches generally rely on distance measures between the generated image and its corresponding ground truth. Despite its ability to produce visually good images, using pixel-based or even…

Computer Vision and Pattern Recognition · Computer Science 2020-02-10 Sébastien de Blois , Ihsen Hedhli , Christian Gagné

Gravitational lensings provide unique opportunities to study distant galaxies. Despite their usefulness, only a dozens of gravitational arcs have been reported up-to-date, hampered by the low resolution imaging from ground-based surveys. We…

Instrumentation and Methods for Astrophysics · Physics 2017-11-10 Chien-Hsiu Lee
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