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Related papers: A new measure for cosmic shear

200 papers

In a recent publication, an aperture mass statistic for gravitational flexion was derived and shown to be effective, at least with simulated data, in detecting massive structures and substructures within clusters of galaxies. Further, it…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Adrienne Leonard , Lindsay J. King

In the very near future, weak lensing surveys will map the projected density of the universe in an unbiased way over large regions of the sky. In order to interpret the results of studies it is helpful to develop an understanding of the…

Astrophysics · Physics 2008-11-26 Dipak Munshi , Peter Coles

Since cosmic shear was first observed in 2000, it has become a key cosmological probe and promises to deliver exquisite dark energy constraints. However, shear is inferred from coherent distortions of galaxy shapes, and the relation between…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-19 Enya Van den Abeele , Pierre Astier , Anna Niemiec

We present simulations of a cosmic shear survey and show how the survey geometry influences the accuracy of determination of cosmological parameters. We numerically calculate the full covariance matrices Cov of two-point statistics of…

Astrophysics · Physics 2009-11-10 Martin Kilbinger , Peter Schneider

We derive cosmological constraints from the probability distribution function (PDF) of evolved large-scale matter density fluctuations. We do this by splitting lines of sight by density based on their count of tracer galaxies, and by…

The weak lensing shear signal has been measured numerically in $N$-body simulations at 14 different redshifts ($z_s = 0.1$ to 3.6) and on angular scales of $\theta = 2'$ to 32'. In addition, the data have been validated by analytical…

Astrophysics · Physics 2009-11-07 Andrew J. Barber

Cosmic shear data contains a large amount of cosmological information encapsulated in the non-Gaussian features of the weak lensing mass maps. This information can be extracted using non-Gaussian statistics. We compare the constraining…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-20 Dominik Zürcher , Janis Fluri , Raphael Sgier , Tomasz Kacprzak , Alexandre Refregier

We propose a novel method to detect cosmic magnification signals by cross-correlating foreground convergence fields constructed from galaxy shear measurements with background galaxy positional distributions, namely shear-number density…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-07 Xiangkun Liu , Dezi Liu , Zucheng Gao , Chengliang Wei , Guoliang Li , Liping Fu , Toshifumi Futamase , Zuhui Fan

Statistics of the weak lensing of galaxies can be used to constrain cosmology if the galaxy shear can be estimated accurately. In general this requires accurate modelling of unlensed galaxy shapes and the point spread function (PSF). I…

Astrophysics of Galaxies · Physics 2009-09-07 Antony Lewis

A cosmic shear survey, spanning a significant proportion of the sky, should greatly improve constraints on a number of cosmological parameters. It also provides a unique opportunity to examine the matter power spectrum directly. However,…

Astrophysics · Physics 2009-11-13 Fergus Simpson

We report on the marginal detection of cosmic shear on sub-arcmin scales with archive data from the STIS camera on board HST. For the measurement 121 galaxy fields with a field of view of 51'' x 51'' are used to obtain an rms cosmic shear…

We present a combined cosmic shear analysis of the modeling of line-of-sight distortions on strongly lensed extended arcs and galaxy shape measurements in the COSMOS field. We develop a framework to predict the covariance of strong lensing…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-14 Felix Arjun Kuhn , Claudio Bruderer , Simon Birrer , Adam Amara , Alexandre Réfrégier

We develop an algorithm for the reconstruction of the two-dimensional mass distribution of a gravitational lens from the observable distortion of background galaxies. From the measured reduced shear, the lens mapping is obtained, from which…

Astrophysics · Physics 2009-10-31 Tarun Deep Saini , Somak Raychaudhury

Recent cosmic shear analyses have exhibited discrepancies of up to $1\sigma$ between the inferred cosmological parameters when analyzing summary statistics in real space versus harmonic space. In this paper, we demonstrate the consistent…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-23 Andy Park , Sukhdeep Singh , Xiangchong Li , Rachel Mandelbaum , Tianqing Zhang

To develop galaxy-targeting approaches, the gravitational-wave community built a catalog of stellar mass in the local universe based on the 2MASS spectroscopic and photometric redshift surveys. By cleaning and supplementing this catalog,…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-08 J. Biteau

It is generally believed that the spatial distribution of galaxies does not trace that of the total mass. The understanding of the bias effect is therefore necessary to determine the cosmological parameters and the primordial density…

Astrophysics · Physics 2009-10-30 A. Taruya , K. Koyama , J. Soda

We present high signal-to-noise measurements of three-point shear correlations and the third moment of the mass aperture statistic using the first 3 years of data from the Dark Energy Survey. We additionally obtain the first measurements of…

We propose to measure the weak cosmic shear using the spatial derivatives of the galaxy surface brightness field. The measurement should be carried out in Fourier space, in which the point spread function (PSF) can be transformed to a…

Astrophysics · Physics 2009-11-11 Jun Zhang

The determination of the density parameter $\Omega_0$ from the large-scale distribution of galaxies is one of the major goals of modern cosmology. However, if galaxies are biased tracers of the underlying mass distribution, linear…

Astrophysics · Physics 2015-06-24 Licia Verde , Alan F. Heavens , Sabino Matarrese , Lauro Moscardini