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Related papers: The effect of intrinsic alignments on weak lensing…

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The intrinsic alignments of galaxies are recognised as a contaminant to weak gravitational lensing measurements. In this work, we study the alignment of galaxy shapes and spins at low redshift ($z\sim 0.5$) in Horizon-AGN, an…

Intrinsic galaxy alignments constitute the major astrophysical systematic of forthcoming weak gravitational lensing surveys but also yield unique insights into galaxy formation and evolution. We build analytic models for the distribution of…

Cosmology and Nongalactic Astrophysics · Physics 2014-02-07 B. Joachimi , E. Semboloni , S. Hilbert , P. E. Bett , J. Hartlap , H. Hoekstra , P. Schneider

Intrinsic alignments of galaxies are measured and modelled to gain cosmological information, to further understand the interactions between galaxies and to mitigate their effects on gravitational weak lensing studies. Hydrodynamical…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-25 Marloes van Heukelum , Dennis Neumann , Marta Garcia Escobar , Nora Elisa Chisari , Henk Hoekstra

Galaxy formation theories predict that galaxy shapes and angular momenta have non-random alignments with the cosmic web. This leads to so-called intrinsic alignment between pairs of galaxies, which is important to quantify as a nuisance…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-13 Benjamin Zhang , Khee-Gan Lee , Alex Krolewski , Jingjing Shi , Benjamin Horowitz , Robin Kooistra

Intrinsic alignments (IA) of galaxies is one of the key secondary signals to cosmic shear measurements, and must be modeled to interpret weak lensing data and infer the correct cosmology. There are large uncertainties in the physical…

Intrinsic alignments of galaxies can mimic to an extent the effects of shear caused by weak gravitational lensing. Previous studies have shown that for shallow surveys with median redshifts z_m = 0.1, the intrinsic alignment dominates the…

Astrophysics · Physics 2009-11-07 Catherine Heymans , Alan Heavens

We investigate the potential of weak gravitational lensing maps to differentiate between distinct cosmological models, considering cosmic variance due to a limited map extension and the presence of noise. We introduce a measure of the…

Astrophysics · Physics 2009-11-07 Antonio Guimarães

The intrinsic alignment of galaxies is an important systematic effect in weak-lensing surveys, which can affect the derived cosmological parameters. One direct way to distinguish different alignment models and quantify their effects on the…

Correlations between the intrinsic shapes of galaxies and the large-scale galaxy density field provide an important tool to investigate galaxy intrinsic alignments, which constitute a major astrophysical systematic in cosmological weak…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-01 B. Joachimi , R. Mandelbaum , F. B. Abdalla , S. L. Bridle

We study how well the Gaussian approximation is valid for computing the covariance matrices of the convergence power and bispectrum in weak gravitational lensing analyses. We focus on its impact on the cosmological parameter estimations by…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Masanori Sato , Takahiro Nishimichi

Subject of this paper are the statistical properties of ellipticity alignments between galaxies evoked by their coupled angular momenta. Starting from physical angular momentum models, we bridge the gap towards ellipticity correlations,…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-15 Federica Capranico , Philipp Merkel , Bjoern Malte Schaefer

Future weak lensing surveys will directly probe the density fluctuation in the universe. Recent studies have shown how the statistics of the weak lensing convergence field is related to the statistics of collapsed objects. Extending earlier…

Astrophysics · Physics 2008-11-26 Dipak Munshi

The recently discovered discrepancy between galaxy mass measurements from weak lensing and predictions from abundance matching questions our understanding of cosmology, or of the galaxy-halo connection, or of both. We re-examined this…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-05 Jacob Svensmark , Davide Martizzi , Adriano Agnello

Weak gravitational lensing induces flux dependent fluctuations in the observed galaxy number density distribution. This cosmic magnification (magnification bias) effect in principle enables lensing reconstruction alternative to cosmic shear…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-04 Ruijie Ma , Pengjie Zhang , Yu Yu , Jian Qin

Weak gravitational lensing has become a powerful probe of large-scale structure and cosmological parameters. Precision weak lensing measurements require an understanding of the intrinsic alignment of galaxy ellipticities, which can in turn…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Jonathan Blazek , Matthew McQuinn , Uros Seljak

The topology of weak lensing fields is studied using the 2-dimensional genus statistic. Simulated fields of the weak lensing convergence are used to focus on the effect of nonlinear gravitional evolution and to model the statistical errors…

Astrophysics · Physics 2009-10-31 Takahiko Matsubara , Bhuvnesh Jain

Cosmic shear surveys have great promise as tools for precision cosmology, but can be subject to systematic errors including intrinsic ellipticity correlations of the source galaxies. The intrinsic alignments are believed to be small for…

Astrophysics · Physics 2010-10-28 Christopher M. Hirata , Uros Seljak

Many recent studies have demonstrated that scaling arguments, such as the so-called hierarchical {\em ansatz}, are extremely useful in understanding the statistical properties of weak gravitational lensing. This is especially true on small…

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

We use galaxies from the IllustrisTNG, MassiveBlack-II and Illustris hydrodynamic simulations to investigate the behaviour of large scale galaxy intrinsic alignments. Our analysis spans four redshift slices over the approximate range of…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-22 S. Samuroff , R. Mandelbaum , J. Blazek

Weak gravitational lensing (WL) causes distortions of galaxy images and probes massive structures on large scales, allowing us to understand the late-time evolution of the Universe. One way to extract the cosmological information from WL is…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-14 Chieh-An Lin