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Related papers: Improving the Accuracy of Cosmic Magnification Sta…

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The statistical analysis of cosmic large-scale structure is most often based on simple two-point summary statistics, like the power spectrum or the two-point correlation function of a sample of galaxies or other types of tracers. In…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-23 Eniko Regos , Volker Springel , Sownak Bose , Boryana Hadzhiyska , Cesar Hernandez-Aguayo

Weak lensing magnification probes the correlation between galaxies and the underlying matter field in a similar fashion to galaxy-galaxy lensing shear. Although it has long been sidelined in favor of the latter on the grounds of a poorer…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-28 Marcos M. Cueli , Joaquín González-Nuevo , Laura Bonavera , Andrea Lapi

We consider the effect of lensing magnification on high redshift sources in the case that magnification varies on the sky, as expected in wide fields of view or within observed galaxy clusters. We give expressions for number counts, flux…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Bhuvnesh Jain , Marcos Lima

We present a novel approach to measuring the expansion rate and the geometry of the Universe, which combine time-delay cosmography in lens galaxy clusters with pure samples of 'cosmic chronometers' (CCs) by probing the member galaxies. The…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-11 P. Bergamini , S. Schuldt , A. Acebron , C. Grillo , U. Mestric , G. Granata , G. B. Caminha , M. Meneghetti , A. Mercurio , P. Rosati , S. H. Suyu , E. Vanzella

Computing the inverse covariance matrix (or precision matrix) of large data vectors is crucial in weak lensing (and multi-probe) analyses of the large scale structure of the universe. Analytically computed covariances are noise-free and…

Instrumentation and Methods for Astrophysics · Physics 2017-12-06 Oliver Friedrich , Tim Eifler

We propose to use a simple observable, the fractional area of "hot spots" in weak gravitational lensing mass maps which are detected with high significance, to determine background cosmological parameters. Because these high-convergence…

Astrophysics · Physics 2011-02-11 Sheng Wang , Zoltán Haiman , Morgan May

We investigate the impact of the observed correlation between a galaxies shape and its surrounding density field on the measurement of third order weak lensing shear statistics. Using numerical simulations, we estimate the systematic error…

Weak gravitational lensing has become an important tool to study the properties of dark matter halos around galaxies, thanks to the advent of large panoramic cameras on 4m class telescopes. This area of research has been developing rapidly…

Astrophysics · Physics 2009-11-11 Henk Hoekstra

The unprecedented amount and the excellent quality of lensing data that the upcoming ground- and space-based surveys will produce represent a great opportunity to shed light on the questions that still remain unanswered concerning our…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-27 Carolina Parroni , Edouard Tollet , Vincenzo F. Cardone , Roberto Maoli , Roberto Scaramella

In these lectures I give an overview of gravitational lensing, concentrating on theoretical aspects, including derivations of some of the important results. Topics covered include the determination of surface mass densities of intervening…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-08 Alan Heavens

Upcoming galaxy surveys will allow us to probe the growth of the cosmic large-scale structure with improved sensitivity compared to current missions, and will also map larger areas of the sky. This means that in addition to the increased…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-31 Matteo Martinelli , Roohi Dalal , Fereshteh Majidi , Yashar Akrami , Stefano Camera , Elena Sellentin

Microlensing of stars in strongly lensed galaxies can lead to temporary extreme magnification factors ($\mu\!>\!1000$), enabling their detection at high redshifts. Following the discovery of Icarus, several stars at cosmological distances…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-03 J. M. Palencia , J. M. Diego , B. J. Kavanagh , J. Martinez

Weak lensing is one of the best available diagnostic tools to measure the total density profiles of distant clusters of galaxies. Unfortunately, it suffers from the well-known mass-sheet degeneracy, so that weak lensing analyses cannot lead…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Alessandro Sonnenfeld , Giuseppe Bertin , Marco Lombardi

We present a concept study on weak lensing map reconstruction through the cosmic magnification effect in galaxy number density distribution. We propose a minimal variance linear estimator to minimize both the dominant systematical and…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-16 Xinjuan Yang , Pengjie Zhang

The apparent sizes and brightnesses of galaxies are correlated in a dipolar pattern around matter overdensities in redshift space, appearing larger on their near side and smaller on their far side. The opposite effect occurs for galaxies…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-09 Sambatra Andrianomena , Camille Bonvin , David Bacon , Philip Bull , Chris Clarkson , Roy Maartens , Teboho Moloi

We present forecast results for constraining the primordial non-Gaussianity from photometric surveys through a large-scale enhancement of the galaxy clustering amplitude. In photometric surveys, the distribution of observed galaxies at high…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Toshiya Namikawa , Tomohiro Okamura , Atsushi Taruya

The main goal of this work, the second in a three-paper series, is to test the impact of a methodological improvement in measuring the magnification bias signal on a sample of submillimeter galaxies and its implications for constraining…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-09 Marcos M. Cueli , Joaquín González-Nuevo , Laura Bonavera , Andrea Lapi , David Crespo , José Manuel Casas

Several cosmological measurements have attained significant levels of maturity and accuracy over the last decade. Continuing this trend, future observations promise measurements of the statistics of the cosmic mass distribution at an…

Astrophysics · Physics 2008-11-26 Salman Habib , Katrin Heitmann , David Higdon , Charles Nakhleh , Brian Williams

We use numerical simulations of ray tracing through N-body simulations to investigate weak lensing by large-scale structure. These are needed for testing the analytic predictions of two-point correlators, to set error estimates on them and…

Astrophysics · Physics 2007-05-23 Bhuvnesh Jain , Uros Seljak , Simon White

Gravitational lensing surveys have now become large and precise enough that the interpretation of the lensing signal has to take into account an increasing number of theoretical limitations and observational biases. Since the lensing signal…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Joachim Harnois-Deraps , Sanaz Vafaei , Ludovic Van Waerbeke