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Related papers: Weak Lensing Skew-Spectrum

200 papers

Weak gravitational lensing on a cosmological scales can provide strong constraints both on the nature of dark matter and the dark energy equation of state. Most current weak lensing studies are restricted to (two-dimensional) projections,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Dipak Munshi , Alan Heavens , Peter Coles

We address key points for an efficient implementation of likelihood codes for modern weak lensing large-scale structure surveys. Specifically, we focus on the joint weak lensing convergence power spectrum-bispectrum probe and we tackle the…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-02 Matteo Rizzato , Karim Benabed , Francis Bernardeau , Fabien Lacasa

Optical weak lensing surveys have become a powerful tool for precision cosmology, but remain subject to systematic effects that can severely bias cosmological parameter estimates if not carefully removed. We discuss the possibility of…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-22 Philip Bull , Ian Harrison , Eric Huff

We present a tomographic cosmological weak lensing analysis of the HST COSMOS Survey. Applying our lensing-optimized data reduction, principal component interpolation for the ACS PSF, and improved modelling of charge-transfer inefficiency,…

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 present novel statistical tools to cross-correlate frequency cleaned thermal Sunyaev-Zel'dovich (tSZ) maps and tomographic weak lensing (wl) convergence maps. Moving beyond the lowest order cross-correlation, we introduce a hierarchy of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Dipak Munshi , Shahab Joudaki , Peter Coles , Joseph Smidt , Scott T. Kay

The present generation of weak lensing surveys will be superseded by surveys run from space with much better sky coverage and high level of signal to noise ratio, such as SNAP. However, removal of any systematics or noise will remain a…

Astrophysics · Physics 2009-11-10 Dipak Munshi , Patrick Valageas

Weak gravitational lensing measurements are traditionally made at optical wavelengths where many highly resolved galaxy images are readily available. However, the Square Kilometre Array (SKA) holds great promise for this type of measurement…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-19 Prina Patel , Ian Harrison , Sphesihle Makhathini , Filipe Abdalla , David Bacon , Michael L. Brown , Ian Heywood , Matt Jarvis , Oleg Smirnov

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

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

Measurements of ellipticities of background galaxies are sensitive to the reduced shear, the cosmic shear divided by $(1-\kappa)$ where $\kappa$ is the projected density field. We compute the difference between shear and reduced shear both…

Astrophysics · Physics 2008-11-26 Scott Dodelson , Charles Shapiro , Martin White

We update the field-level inference code KARMMA to enable tomographic forward-modelling of shear maps. Our code assumes a lognormal prior on the convergence field, and properly accounts for the cross-covariance in the lensing signal across…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-11 Supranta S. Boruah , Pier Fiedorowicz , Eduardo Rozo

We propose counting peaks in weak lensing (WL) maps, as a function of their height, to probe models of dark energy and to constrain cosmological parameters. Because peaks can be identified in two-dimensional WL maps directly, they can…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-06 Jan M. Kratochvil , Zoltán Haiman , Morgan May

Weak gravitational lensing is becoming a mature technique for constraining cosmological parameters, and future surveys will be able to constrain the dark energy equation of state $w$. When analyzing galaxy surveys, redshift information has…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-07 Andrea Petri , Morgan May , Zoltán Haiman

With the availability of thousands of type Ia supernovae in the near future the magnitude scatter induced by lensing will become a major issue as it affects parameter estimation. Current N-body simulations are too time consuming to be…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-10 Valerio Marra , Miguel Quartin , Luca Amendola

We develop a method for estimating the shear power spectra from weak lensing observations and test it on simulated data. Our method describes the shear field in terms of angular power spectra and cross correlation of the two shear modes…

Astrophysics · Physics 2008-11-26 Wayne Hu , Martin White

Lensing peaks have been proposed as a useful statistic, containing cosmological information from non-Gaussianities that is inaccessible from traditional two-point statistics such as the power spectrum or two-point correlation functions.…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-05 Jia Liu , Andrea Petri , Zoltan Haiman , Lam Hui , Jan M. Kratochvil , Morgan May

Weak gravitational lensing observations probe the spectrum and evolution of density fluctuations and the cosmological parameters which govern them. At low redshifts, the non-linear gravitational evolution of large scale structure produces a…

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

As weak lensing surveys become deeper, they reveal more non-Gaussian aspects of the convergence field which can only be extracted using statistics beyond the power spectrum. In Cheng et al. (2020) we showed that the scattering transform, a…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-07 Sihao Cheng , Brice Ménard

Weak gravitational lensing provides a sensitive probe of cosmology by measuring the mass distribution and the geometry of the low redshift universe. We show how an all-sky weak lensing tomographic survey can jointly constrain different sets…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-31 Ivan Debono , Anais Rassat , Alexandre Refregier , Adam Amara , Thomas D. Kitching