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Related papers: Statistics of Weak Gravitational Lensing in Cold D…

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We investigate the effects of weak gravitational lensing in the standard Cold Dark Matter cosmology, using an algorithm which evaluates the shear in three dimensions. The algorithm has the advantage of variable softening for the particles,…

Astrophysics · Physics 2009-10-31 Andrew J. Barber , Peter A. Thomas , H. M. P. Couchman

We present the results of weak gravitational lensing statistics in four different cosmological $N$-body simulations. The data has been generated using an algorithm for the three-dimensional shear, which makes use of a variable softening…

Astrophysics · Physics 2009-10-31 Andrew J. Barber , Peter A. Thomas , H. M. P. Couchman , C. J. Fluke

We perform high resolution ray-tracing simulations to investigate probability distribution functions (PDFs) of lensing convergence, shear, and magnification on distant sources up to the redshift of $z_s=20$. We pay particular attention to…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Ryuichi Takahashi , Masamune Oguri , Masanori Sato , Takashi Hamana

Weak lensing can be observed through a number of effects on the images of distant galaxies; their shapes are sheared, their sizes and fluxes (magnitudes) are magnified and their positions on the sky are modified by the lensing field. Galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-12 Justin Alsing , Donnacha Kirk , Alan Heavens , Andrew Jaffe

Weak gravitational lensing surveys are rapidly becoming important tools to probe directly the mass density fluctuations in the universe and its background dynamics. Earlier studies have shown that it is possible to model the statistics of…

Astrophysics · Physics 2009-11-07 Patrick Valageas , Andrew J. Barber , Dipak Munshi

We study how joint shear and magnification measurements improve the statistical precision of weak lensing mass calibration experiments, relative to standard shear-only analysis. For our magnification measurements, we consider not only the…

Cosmology and Nongalactic Astrophysics · Physics 2010-09-30 Eduardo Rozo , Fabian Schmidt

Weak gravitational lensing observations probe the spectrum and evolution of density fluctuations and the cosmological parameters which govern them. The non-linear evolution of large scale structure produces a non-Gaussian signal which is…

Astrophysics · Physics 2009-10-31 Asantha Cooray , Wayne Hu

The weak lensing surveys have the potential to probe directly the clustering statistics of dark matter in the universe. Recent studies have shown that it is possible to predict analytically the whole probability distribution function (pdf)…

Astrophysics · Physics 2009-11-07 Dipak Munshi

We study the weak gravitational lensing effects caused by a stochastic distribution of dark matter halos. We develop a simple approach to calculate the magnification probability distribution function which allows us to easily compute the…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-04 Kimmo Kainulainen , Valerio Marra

We investigate the weak lensing effects of line-of-sight structures on quadruple images in quasar-galaxy strong lens systems based on N-body and ray-tracing simulations that can resolve halos with a mass of 10^5 solar mass. The intervening…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Ryuichi Takahashi , Kaiki Taro Inoue

We present a derivation of a generalized optimally-weighted estimator for the weak lensing magnification signal, including a calculation of errors. With this estimator, we present a local method for optimally estimating the local effects of…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-27 Bryan Gillis , Andy Taylor

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

We use weak gravitational lensing to measure mean mass profiles around Locally Brightest Galaxies (LBGs). These are selected from the SDSS/DR7 spectroscopic and photometric catalogues to be brighter than any neighbour projected within 1.0…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-15 Wenting Wang , Simon White , Rachel Mandelbaum , Bruno Henriques , Michael E. Anderson , Jiaxin Han

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

We present new results on the gravitational lensing shear and magnification power spectra obtained from numerical simulations of a flat cosmology with a cosmological constant. These results are of considerable interest since both the shear…

Astrophysics · Physics 2009-11-07 Andrew J. Barber , A. N. Taylor

Weak gravitational lensing is responsible for the shearing and magnification of the images of high-redshift sources due to the presence of intervening matter. The distortions are due to fluctuations in the gravitational potential, and are…

Astrophysics · Physics 2009-09-29 D. Munshi , P. Valageas , L. Van Waerbeke , A. Heavens

In this article we present an analytic calculation of the probability distribution of the magnification of distant sources due to weak gravitational lensing from non-linear scales. We use a realistic description of the non-linear density…

Astrophysics · Physics 2011-05-23 P. Valageas

We investigate the influence of the inner profile of lens objects on gravitational lens statistics taking into account of the effect of magnification bias and both the evolution and the scatter of halo profiles. We take the dark halos as…

Astrophysics · Physics 2009-11-06 Ryuichi Takahashi , Takeshi Chiba

Density fluctuations in the matter distribution lead to distortions of the images of distant galaxies through weak gravitational lensing effects. This provides an efficient probe of the cosmological parameters and of the density field. In…

Astrophysics · Physics 2007-05-23 P. Valageas
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