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Related papers: On Scale-Dependent Cosmic Shear Systematic Effects

200 papers

We investigate the prospects for using the weak lensing bispectrum alongside the power spectrum to control systematic uncertainties in a Euclid-like survey. Three systematic effects are considered: the intrinsic alignment of galaxies,…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-02 Susan Pyne , Benjamin Joachimi

We identify and study a previously unknown systematic effect on cosmic shear measurements, caused by the selection of galaxies used for shape measurement, in particular the rejection of close (blended) galaxy pairs. We use ray-tracing…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Jan Hartlap , Stefan Hilbert , Peter Schneider , Hendrik Hildebrandt

In the absence of any compelling physical model, cosmological systematics are often misrepresented as statistical effects and the approach of marginalising over extra nuisance systematic parameters is used to gauge the effect of the…

Astrophysics · Physics 2009-10-20 T. D. Kitching , A. Amara , F. B. Abdalla , B. Joachimi , A. Refregier

We conduct a comprehensive study into the impact of pixelization on cosmic shear, uncovering several sources of bias in standard pseudo-$C_\ell$ estimators based on discrete catalogues. We derive models that can bring residual biases to the…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-04 Alex Hall , Nicolas Tessore

We present a semi-analytic model for the shear two-point correlation function of a cosmic shear survey with non-uniform depth. Ground-based surveys are subject to depth variations that primarily arise through varying atmospheric conditions.…

Weak lensing by large-scale structure is an invaluable cosmological tool given that most of the energy density of the concordance cosmology is invisible. Several large ground-based imaging surveys will attempt to measure this effect over…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-18 Eric M. Huff , Christopher M. Hirata , Rachel Mandelbaum , David Schlegel , Uros Seljak , Robert H. Lupton

We consider the impact of key astrophysical and measurement systematics on constraints on dark energy and modifications to gravity on cosmic scales. We focus on upcoming photometric "Stage III" and "Stage IV" large scale structure surveys…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Istvan Laszlo , Rachel Bean , Donnacha Kirk , Sarah Bridle

Weak lensing observations have the potential to be even more powerful than cosmic microwave background (CMB) observations in constraining cosmological parameters. However, the practical limits to weak lensing observations are not known.…

Astrophysics · Physics 2009-11-13 D. Wittman

Current and future imaging surveys will measure cosmic shear with a statistical precision that demands a deeper understanding of potential systematic biases in galaxy shape measurements than has been achieved to date. We investigate the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 J. E. Meyers , P. R. Burchat

The statistics of shear peaks have been shown to provide valuable cosmological information beyond the power spectrum, and will be an important constraint of models of cosmology with the large survey areas provided by forthcoming…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-15 Deborah Bard , Jan M. Kratochvil , William Dawson

In order to reach the required performance of Stage-III and IV weak lensing surveys, cosmic shear measurements have to rely on external simulations to calibrate residual biases. Over the years, several techniques have been developed to…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-11 G. Congedo , A. N. Taylor

We present new tests to identify stationary position-dependent additive shear biases in weak gravitational lensing data sets. These tests are important diagnostics for currently ongoing and planned cosmic shear surveys, as such biases…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-24 Edo van Uitert , Peter Schneider

In this paper we derive a full expression for the propagation of multiplicative and additive shape measurement biases into the cosmic shear power spectrum. In doing so we identify several new terms that are associated with selection…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-16 T. D. Kitching , P. Paykari , H. Hoekstra , M. Cropper

Validating modeling choices through simulated analyses and quantifying the impact of different systematic effects will form a major computational bottleneck in the preparation for 3$\times$2 analysis with Stage-IV surveys such as Vera Rubin…

In this third paper of a series on radio weak lensing for cosmology with the Square Kilometre Array, we scrutinise synergies between cosmic shear measurements in the radio and optical/near-IR bands for mitigating systematic effects. We…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-19 Stefano Camera , Ian Harrison , Anna Bonaldi , Michael L. Brown

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

Galaxy clusters are a recent cosmological probe. The precision and accuracy of the cosmological parameters inferred from these objects are affected by the knowledge of cluster physics, entering the analysis through the mass-observable…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-28 Laura Salvati , Marian Douspis , Nabila Aghanim

Gravitational lensing shear has the potential to be the most powerful tool for constraining the nature of dark energy. However, accurate measurement of galaxy shear is crucial and has been shown to be non-trivial by the Shear TEsting…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 L. M. Voigt , S. L. Bridle

Cosmic shear leads to a correlation of the observed ellipticities of galaxies, an effect which is used to place constraints on cosmological parameters, and to explore the evolution of dark matter and dark energy in the universe. However, a…

Astrophysics · Physics 2009-11-11 Lindsay King

The LSST survey will provide unprecedented statistical power for measurements of dark energy. Consequently, controlling systematic uncertainties is becoming more important than ever. The LSST observing strategy will affect the statistical…