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Related papers: The Origin of Weak Lensing Convergence Peaks

200 papers

Standard cosmology has many successes on large scales, but faces some fundamental difficulties on small, galactic scales. One such difficulty is the cusp/core problem. High resolution observations of the rotation curves for dark matter…

Astrophysics · Physics 2010-11-30 Da-Ming Chen , Stacy McGaugh

Locating the centers of dark matter halos is critical for understanding the mass profiles of halos as well as the formation and evolution of the massive galaxies that they host. The task is observationally challenging because we cannot…

Low Density Points (LDPs, \citet{2019ApJ...874....7D}), obtained by removing high-density regions of observed galaxies, can trace the Large-Scale Structures (LSSs) of the universe. In particular, it offers an intriguing opportunity to…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-21 Fuyu Dong , Pengjie Zhang , Le Zhang , Ji Yao , Zeyang Sun , Changbom Park , Xiaohu Yang

Weak gravitational lensing of distant galaxies by foreground structures has proven to be a powerful tool to study the mass distribution in the universe. The advent of panoramic cameras on 4m class telescope has led to a first generation of…

Astrophysics · Physics 2019-10-23 Henk Hoekstra

If the dark matter halos of galaxies contain large numbers of subhalos as predicted by the $\Lambda$CDM model, these subhalos are expected to appear in strong galaxy--galaxy lens systems as small--scale perturbations in individual images.…

Astrophysics of Galaxies · Physics 2017-09-13 Saghar Asadi , Erik Zackrisson , Emily Freeland

We report a measurement of cosmic shear correlations using an effective area of 6.5 sq. deg. of the VIRMOS deep imaging survey in progress at the Canada-France-Hawaii Telescope. We measured various shear correlation functions, the aperture…

It is conventional to calculate the probability of microlensing for a cosmologically distant source based on the Press-Gunn approximation that the lensing objects are uniformly and randomly distributed in the intervening space with a…

Astrophysics · Physics 2009-11-07 J. S. B. Wyithe , E. L. Turner

Weak gravitational lensing of distant galaxies by foreground structures has proven to be a powerful tool to study the mass distribution in the universe. Nowadays, attention has shifted from clusters of galaxies to the statistical properties…

Astrophysics · Physics 2009-11-07 Henk Hoekstra , Howard Yee , Mike Gladders

We investigate the effect of weak gravitational lensing in the limit of small angular scales where projected galaxy clustering is strongly nonlinear. This is the regime likely to be probed by future weak lensing surveys. We use…

Astrophysics · Physics 2009-10-31 Dipak Munshi , Peter Coles

Low density regions are less affected by the nonlinear structure formation and baryonic physics. They are ideal places for probing the nature of dark energy, a possible explanation for the cosmic acceleration. Unlike void lensing, which…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-12 Fuyu Dong , Jun Zhang , Yu Yu , Xiaohu Yang , Hekun Li , Jiaxin Han , Wentao Luo , Jiajun Zhang , Liping Fu

Recent analyses show that $\Lambda$CDM-based models optimised to reproduce the clustering of massive galaxies overestimate their gravitational lensing by about 30\%, the so-called lensing is low problem. Using a state-of-the-art…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-15 Jonas Chaves-Montero , Raul E. Angulo , Sergio Contreras

We analyse the impact of galaxy--halo misalignment on the ability of weak lensing studies to constrain the shape of dark matter haloes, using a combination of the Millennium dark matter N-body simulation and different semi-analytic galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-07 Philip E. Bett

We present constraints on the amplitude and shape of the matter power spectrum and the density of dark matter within the framework of a standard LambdaCDM model. We use a Markov Chain Monte Carlo approach to combine independent measurements…

Astrophysics · Physics 2008-11-26 J. Lesgourgues , M. Viel , M. G. Haehnelt , R. Massey

We investigate the weak gravitational lensing effect due to the large-scale structure of the universe on two-point correlations of local maxima ({\em hotspots}) in the 2D sky map of the cosmic microwave background (CMB) anisotropy.…

Astrophysics · Physics 2016-08-30 Masahiro Takada , Eiichiro Komatsu , Toshifumi Futamase

Galaxy clusters identified with optical imaging tend to suffer from projection effects, which impact richness (the number of member galaxies in a cluster) and lensing coherently. Physically unassociated galaxies can be mistaken as cluster…

We study the impact of baryonic processes and massive neutrinos on weak lensing peak statistics that can be used to constrain cosmological parameters. We use the BAHAMAS suite of cosmological simulations, which self-consistently include…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-09 Matthew Fong , Miyoung Choi , Victoria Catlett , Brandyn Lee , Austin Peel , Rachel Bowyer , Lindsay J. King , Ian G. McCarthy

We present a Bayesian graph neural network (BGNN) that can estimate the weak lensing convergence ($\kappa$) from photometric measurements of galaxies along a given line of sight. The method is of particular interest in strong gravitational…

The study of the magnification bias produced on high-redshift sub-millimetre galaxies by foreground galaxies through the analysis of the cross-correlation function was recently demonstrated as an interesting independent alternative to the…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-24 J. Gonzalez-Nuevo , M. M. Cueli , L. Bonavera , A. Lapi , M. Migliaccio , F. Argüeso , L. Toffolatti

The weak gravitational lensing effect, small coherent distortions of galaxy images by means of a gravitational tidal field, can be used to study the relation between the matter and galaxy distribution. In this context, weak lensing has so…

Astrophysics · Physics 2014-11-18 P. Simon , P. Watts , P. Schneider , H. Hoekstra , M. D. Gladders , H. K. C. Yee , B. C. Hsieh , H. Lin

We present a Bayesian hierarchical inference formalism to study the relation between the properties of dark matter halos and those of their central galaxies using weak gravitational lensing. Unlike traditional methods, this technique does…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-11 Alessandro Sonnenfeld , Alexie Leauthaud