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Related papers: Reduced Shear Power Spectrum

200 papers

Yes! Upcoming galaxy shear surveys have the potential to significantly improve our understanding of dark energy and neutrino mass if lensing systematics can be sufficiently controlled. The cross-correlations between the weak lensing shear,…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-12 Sudeep Das , Josquin Errard , David Spergel

We develop a method for general non-linear cluster lens reconstruction using the observable distortion of background galaxies. The distortion measures the combination $\gamma/(1-\kappa)$ of shear $\gamma$ and surface density $\kappa$. From…

Astrophysics · Physics 2009-10-22 Nick Kaiser

Weak lensing alters the size of images with a similar magnitude to the distortion due to shear. Galaxy size probes the convergence field, and shape the shear field, both of which contain cosmological information. We show the gains expected…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Alan Heavens , Justin Alsing , Andrew Jaffe

Galaxies modeled as singular isothermal ellipsoids with an axis ratio distribution similar to the observed axis ratio distribution of E and S0 galaxies are statistically consistent with both the observed numbers of two-image and four-image…

Astrophysics · Physics 2009-10-28 C. R. Keeton , C. S. Kochanek , U. Seljak

By obtaining photometric redshift information, tomography allows us to cross-correlate galaxy ellipticities in different source redshift bins. The cross-correlation is non-vanishing because the different bins share much of the foreground…

Astrophysics · Physics 2009-11-10 Masahiro Takada , Martin White

Cosmic shear estimation is an essential scientific goal for large galaxy surveys. It refers to the coherent distortion of distant galaxy images due to weak gravitational lensing along the line of sight. It can be used as a tracer of the…

Machine Learning · Computer Science 2021-04-21 Claire Theobald , Bastien Arcelin , Frédéric Pennerath , Brieuc Conan-Guez , Miguel Couceiro , Amedeo Napoli

In cosmic shear likelihood analyses the covariance is most commonly assumed to be constant in parameter space. Therefore, when calculating the covariance matrix (analytically or from simulations), its underlying cosmology should not…

Astrophysics · Physics 2015-05-13 Tim Eifler , Peter Schneider , Jan Hartlap

We investigate the extent to which cosmic size magnification may be used to com- plement cosmic shear in weak gravitational lensing surveys, with a view to obtaining high-precision estimates of cosmological parameters. Using simulated…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Biuse Casaponsa , Alan F. Heavens , Tom D. Kitching , Lance Miller , Rita Belén Barreiro , Enrique Martínez-Gonzalez

Cosmic shear is a powerful probe of cosmological distances, matter abundance and clustering in the low-redshift Universe. Cosmological parameter extraction from cosmic shear data is limited by our understanding of baryonic astrophysics,…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-31 Shi-Fan Chen , Joseph DeRose , Mikhail M. Ivanov , Oliver H. E. Philcox

Weak gravitational lensing provides a unique method to directly measure the distribution of mass in the universe. Because the distortions induced by lensing in the shape of background galaxies are small, the measurement of weak lensing…

Astrophysics · Physics 2009-11-06 Alexandre Refregier , David Bacon

We propose a new technique to directly measure the shapes of dark matter halos of galaxies using weak gravitational lensing. Extending the standard galaxy-galaxy lensing method, we show that the shape parameters of the mass distribution of…

Astrophysics · Physics 2009-10-31 Priyamvada Natarajan , Alexandre Refregier

We derive a new relation between cosological distances, valid in any (statistically) isotropic space-time and independent of cosmological parameters or even the validity of the field equation of General Relativity. In particular, this…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-03 Peter Schneider

Weak lensing by large-scale structure provides a unique method to directly measure matter fluctuations in the universe, and has recently been detected from the ground. Here, we report the first detection of this `cosmic shear' based on…

Astrophysics · Physics 2009-11-06 J. Rhodes , A. Refregier , E. J. Groth

We compute the weak lensing convergence power spectrum, $C^{\kappa\kappa}(\theta)$, in a dust-filled universe using fully non-linear general relativistic simulations. The spectrum is then compared to more standard, approximate calculations…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-29 John T. Giblin , James B. Mertens , Glenn D. Starkman , Andrew R. Zentner

Now that weak lensing signals on the order of a percent are actively being searched for (cosmic shear, galaxy-galaxy lensing, large radii in clusters...) it is important to investigate how accurately weak shears can be determined. Many…

Astrophysics · Physics 2016-08-30 K. Kuijken

We investigate the distortions due to this shear in the microlensing light curves and in the astrometric microlensing centroid shift trajectories. As expected, the light curve deviation increases as the shear increases and the impact…

Astrophysics · Physics 2009-11-13 Yoon-Hyun Ryu , Myeong-Gu Park

The shear triplet statistics is a geometric method to measure cosmological parameters with observations in the weak gravitational lensing regime towards massive haloes. Here, this proposal is considered to probe the dark energy equation of…

Astrophysics · Physics 2008-11-26 Mauro Sereno

Cosmological weak lensing by the large scale structure of the Universe, cosmic shear, is coming of age as a powerful probe of the parameters describing the cosmological model and matter power spectrum. It complements CMB studies, by…

Astrophysics · Physics 2009-11-10 Patrick Simon , Lindsay J. King , Peter Schneider

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

Weak lensing of galaxies by large scale structure can potentially measure cosmological quantities as accurately as the cosmic microwave background (CMB). However, the relation between observables and fundamental parameters is more complex…

Astrophysics · Physics 2009-10-31 Wayne Hu , Max Tegmark